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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 08:13: Since the gas is being compressed but its mass is not changing by much, its density must increase.
	2022-12-08: How Are Quasiparticles Different From Particles? 02:34: It even has an effective positive mass.
	2022-11-23: How To See Black Holes By Catching Neutrinos 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 01:32: ... being that neutrinos are electrically neutral and have much lower masses than the charged ... 01:43: ... extremely low mass of neutrinos means that they tend to travel at very close to the speed ... 08:30: In this case with a mass of around 10 million suns. 16:29: Also, because they have such extreme masses they’d be hard to produce naturally. 17:31: ... at nuclear masses much higher than the current periodic it may be possible for quarks to ... 17:49: ... up-down-quark matter may lead to perfectly stable “nuclei” with atomic masses as low as ... 01:32: ... being that neutrinos are electrically neutral and have much lower masses than the charged ... 16:29: Also, because they have such extreme masses they’d be hard to produce naturally. 17:31: ... at nuclear masses much higher than the current periodic it may be possible for quarks to ... 17:49: ... up-down-quark matter may lead to perfectly stable “nuclei” with atomic masses as low as ... 10:17: This leads to massive amplification of the jet’s light due to Einstein stuff.
	2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table? 03:28: Well, actually technetium is produced in nature - just like other heavy elements, in the core of massive stars.
	2022-10-19: The Equation That Explains (Nearly) Everything! 11:57: ... The particles described by the Lagrangian so far are massless. To add mass we need the Higgs field - and that’s what the rest of the Lagrangian ... 12:23: ... is a matrix with the square of the mass of each different fermion. This equation doesn’t actually predict the ... 12:39: ... but this time hermitian conjugate tells us how antimatter picks up mass from the Higgs field, and it's pretty much the same as regular matter, ... 13:49: ... wavefunction and setting your indices right and including the correct masses, you can calculate behavior of any known particle in the ... 14:00: ... explain. It doesn’t tell us how nature chooses different particle masses, or chooses coupling strengths like the fine structure constant we ... 12:23: ... different fermion. This equation doesn’t actually predict the particle masses - that’s still an unsolved problem. Instead, we have to measure those ... 13:49: ... wavefunction and setting your indices right and including the correct masses, you can calculate behavior of any known particle in the ... 14:00: ... explain. It doesn’t tell us how nature chooses different particle masses, or chooses coupling strengths like the fine structure constant we ... 12:23: ... different fermion. This equation doesn’t actually predict the particle masses - that’s still an unsolved problem. Instead, we have to measure those ... 00:34: But to fit the standard model lagrangian on a coffee mug you need to condense it massively. 12:52: ... how that field changes in space and time and how it interacts with the massive bosons of the weak ... 00:34: But to fit the standard model lagrangian on a coffee mug you need to condense it massively. 11:57: ... getting there. The particles described by the Lagrangian so far are massless. To add mass we need the Higgs field - and that’s what the rest of the ...
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 00:33: ... or so Earth-like planets, at least in terms   of size and mass. Of course if we want to  find life or actually visit these ... 07:45: ... modern materials   that seems possible. Even with that mass, the solar sail would need to be enormous - with   more ... 18:29: ... from particle kinetic energy, photon energy, even particle rest mass. The energy   liberated in the interaction effectively ... 07:45: ... and C) is only a few hundred atoms thick so it doesn’t blow out our mass budget.   Solar sails experience more acceleration  the closer they ... 04:12: ... that gravity is due to curvature in the fabric of spacetime due to massive objects. But   that curvature also bends the path of ...
	2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics? 04:26: And the energy of that ground state electron  is smaller than the rest mass energy of the electron by a factor of 137 squared. 05:34: Those probabilities depend on many things,  like the particles’ positions and momenta, spins, charges, masses, etc. 10:02: There’s no way for the alien civilization to recognize these numbers without knowing our units for distance, time, mass, electric charge, etc. 10:38: ... between two things with the same units, like the ratio of the  mass of the electron and  proton, or the coefficient of friction of an ... 11:20: ... space and time in relativity; it’s also the relationship  between mass and energy in Einstein’s famous ... 11:33: ... gravitational constant is the relationship  between mass, distance, and gravitational force, Planck's Constant is the ... 13:07: Or perhaps it hints at a deeper connection  between the properties of  the elementary particles, like the mass and charge of the electron. 11:33: ... gravitational constant is the relationship  between mass, distance, and gravitational force, Planck's Constant is the relationship  ... 10:02: There’s no way for the alien civilization to recognize these numbers without knowing our units for distance, time, mass, electric charge, etc. 04:26: And the energy of that ground state electron  is smaller than the rest mass energy of the electron by a factor of 137 squared. 05:34: Those probabilities depend on many things,  like the particles’ positions and momenta, spins, charges, masses, etc.
	2022-09-21: Science of the James Webb Telescope Explained! 00:48: Many of you asked whether we were going to do a JWST episode, and at first I thought it wasn’t needed due to the massive coverage. 09:28: Those white blobby things are massive elliptical galaxies of the cluster, several billion light years away. 00:48: Many of you asked whether we were going to do a JWST episode, and at first I thought it wasn’t needed due to the massive coverage. 09:28: Those white blobby things are massive elliptical galaxies of the cluster, several billion light years away. 00:48: Many of you asked whether we were going to do a JWST episode, and at first I thought it wasn’t needed due to the massive coverage. 09:28: Those white blobby things are massive elliptical galaxies of the cluster, several billion light years away.
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 07:19: We know that the Higgs field is what gives most of the standard model particles their masses. 07:24: Well, dark matter definitely has mass - that’s how we know it exists. 07:29: So it wouldn’t be too surprising if it turns out dark matter also gets its mass from the Higgs. 08:48: ... of momentum tells us that the product of velocity times mass of all particles going into a collision has to be the same as the same ... 07:24: Well, dark matter definitely has mass - that’s how we know it exists. 07:19: We know that the Higgs field is what gives most of the standard model particles their masses. 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays.
	2022-08-24: What Makes The Strong Force Strong? 20:38: ... to be coupled strongly with the Higgs field to give the particle enough mass, but it would still need to couple extremely weakly with all other fields ...
	2022-08-17: What If Dark Energy is a New Quantum Field? 03:33: ... all the dark energy in a space the size of the earth and convert it to mass by E=mc^2, you’d only get about a grain of sand’s worth of matter. ...
	2022-08-03: What Happens Inside a Proton? 12:52: ... out that the things you want to calculate,   like the mass of a hadron, DO depend on your choice of pixel size. But they ... 13:36: ... QCD has accurately predicted many things,   from masses and decay frequencies of hadrons to the exotic properties of ...
	2022-07-27: How Many States Of Matter Are There? 06:10: However in the very early universe everything was a quark-gluon plasma, and that may also be true in the cores of massive neutron stars.
	2022-07-20: What If We Live in a Superdeterministic Universe? 16:56: For example, Planck units, or the energies or masses or decay timescales of common particles and elements.
	2022-06-30: Could We Decode Alien Physics? 00:00: ... are distinguishable from each other by   their relative masses, color charge, etc. The  particle running through the alien ... 16:39: ... light sail, you need to to carry your entire deceleration reaction mass with you.   You need to throw as much stuff ahead of you ... 00:00: ... are distinguishable from each other by   their relative masses, color charge, etc. The  particle running through the alien ...
	2022-06-22: Is Interstellar Travel Impossible? 02:47: These craft are little more than computer chips, and sending humans means many orders of magnitude more mass for life support and shielding. 04:02: ... be adequately shielded from tiny particles without adding so much extra mass that accelerating such a ship becomes a practical ... 06:02: It’s 99% gas by mass and 1% very tiny dust grains. 08:19: The kinetic energy deposited by each particles is 1/2 times mass times velocity squared. 08:26: ... in the relative densities, particle masses and speeds, the heat deposited onto our ship by the ISM is around a ... 10:38: There are more advanced options for the latter - for example, deflection of grains by magnetic fields or a shielding mass moving in front of the ship. 13:09: ... around the entire ship would do the trick, but would add a prohibitive mass - too much to accelerate txo relativistic speeds, at least for our early ... 18:50: ... things that can be observed about a black hole from its exterior are mass, spin, and ... 13:09: ... around the entire ship would do the trick, but would add a prohibitive mass - too much to accelerate txo relativistic speeds, at least for our early ... 10:38: There are more advanced options for the latter - for example, deflection of grains by magnetic fields or a shielding mass moving in front of the ship. 18:50: ... things that can be observed about a black hole from its exterior are mass, spin, and ... 08:19: The kinetic energy deposited by each particles is 1/2 times mass times velocity squared. 08:26: ... in the relative densities, particle masses and speeds, the heat deposited onto our ship by the ISM is around a ... 06:41: This stuff comes from heavy elements that are fused in the cores of massive stars and ejected in supernovae or in the winds from giant stars. 09:06: ... leaves permanent scars, with the relatively common oxygen and extra massive iron adding up to most of the ... 12:22: Interstellar space is flooded with high energy particles, from simple protons to massive iron nuclei. 06:41: This stuff comes from heavy elements that are fused in the cores of massive stars and ejected in supernovae or in the winds from giant stars. 09:06: ... leaves permanent scars, with the relatively common oxygen and extra massive iron adding up to most of the ... 12:22: Interstellar space is flooded with high energy particles, from simple protons to massive iron nuclei. 09:06: ... leaves permanent scars, with the relatively common oxygen and extra massive iron adding up to most of the ... 12:22: Interstellar space is flooded with high energy particles, from simple protons to massive iron nuclei. 09:06: ... leaves permanent scars, with the relatively common oxygen and extra massive iron adding up to most of the ... 12:22: Interstellar space is flooded with high energy particles, from simple protons to massive iron nuclei. 06:41: This stuff comes from heavy elements that are fused in the cores of massive stars and ejected in supernovae or in the winds from giant stars.
	2022-06-01: What If Physics IS NOT Describing Reality? 03:22: ... information we have — for example, about  the location or speed or mass of a particle.   Zeilinger calls such a statement a ... 14:22: ... so it’s survived various regions - although it may   be that mass extinction events correlate with  entering more dangerous regions ... 15:25: ... collision? It depends on how head-on the collision  is, and the mass ratio between the stars.   Glancing collisions can result in ... 14:22: ... so it’s survived various regions - although it may   be that mass extinction events correlate with  entering more dangerous regions of the ... 15:25: ... collision? It depends on how head-on the collision  is, and the mass ratio between the stars.   Glancing collisions can result in stars ...
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 11:10: ... the mass of the galaxy approaches, it pulls  the disk of the Milky Way up, ... 12:11: ... And while the Magellanic clouds themselves  are only about 1% the mass of the Milky Way   themselves, the entire stream may be 10 ... 10:34: ... down to punch through the disk three  times. Most importantly, the massive core is still   relatively intact and moving together, so ... 12:11: ... we see them being pulled apart- the Magellanic   Clouds have massive tails that make a great  loop all across the ‘bottom’ half of the ... 13:17: ... meaning that the Milky Way was always   significantly more massive than its meal. That’s  going to change with the final merger of our ... 10:34: ... down to punch through the disk three  times. Most importantly, the massive core is still   relatively intact and moving together, so ... 12:11: ... we see them being pulled apart- the Magellanic   Clouds have massive tails that make a great  loop all across the ‘bottom’ half of the ... 13:17: ... meaning that the Milky Way was always   significantly more massive than its meal. That’s  going to change with the final merger of our ... 10:34: ... down to punch through the disk three  times. Most importantly, the massive core is still   relatively intact and moving together, so ... 12:11: ... we see them being pulled apart- the Magellanic   Clouds have massive tails that make a great  loop all across the ‘bottom’ half of the ... 16:41: ... for life to get started.   The late heavy bombardment was a massive  meteor shower that lasted millions of years,   and probably ... 02:19: ... the disk and halo   and constitutes 80% of the Milky Way’s mass.The entire galaxy is beautiful and intricately   structured. Weird ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 02:06: ... our Sun is objectively mediocre,   average in terms of mass, age, even  location. But consider for a moment   the ... 00:24: ... also seems pretty ideal in a number of ways.   A bit more massive and it would have burned out  too quickly, much less massive and it ... 06:28: ... of these heavy elements are produced in  massive stars and then spread through the galaxy   in supernova ... 00:24: ... also seems pretty ideal in a number of ways.   A bit more massive and it would have burned out  too quickly, much less massive and it ... 06:28: ... of these heavy elements are produced in  massive stars and then spread through the galaxy   in supernova ... 09:26: ... evolution, but life   needs time to recover. Overly frequent mass  extinctions will result in absolute ...
	2022-05-04: Space DOES NOT Expand Everywhere 13:35: ... Participatory Universe, and the episode on the Higgs mechanism and the mass of the W boson. Let’s do the latter ... 13:50: ... The amount by which its path is deflected by that field depends on its mass. In the case of the W boson, the particle actually decays too quickly to ... 04:54: ... in we can see that the shape of the gridlines change. They pull towards massive objects like ... 05:19: ... fact the shape of spacetime around massive objects is NOT the FLRW metric because the matter isn’t spread out ... 04:54: ... in we can see that the shape of the gridlines change. They pull towards massive objects like ... 05:19: ... fact the shape of spacetime around massive objects is NOT the FLRW metric because the matter isn’t spread out ... 04:54: ... in we can see that the shape of the gridlines change. They pull towards massive objects like ... 05:19: ... fact the shape of spacetime around massive objects is NOT the FLRW metric because the matter isn’t spread out evenly. For ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 00:00: ... physicists really care about the  mass of the W boson. They spent nearly a   decade recording ... 00:10: ... in the April 7 announcement  that this obscure particle’s mass seems to be 0.1%   heavier than expected. So why do we care? ... 00:46: ... we once thought no force-carrying  particle should have - they have mass. ... 01:25: ... to  the Higgs mechanism, which not only   explains the mass of the weak bosons, but  teaches us about the nature of mass ... 08:09: ... That self-interaction is what leads to the   property of mass. Gauge fields shouldn’t interact  with themselves, so shouldn’t have ... 10:23: ... change. We’re going   to switch the sign in front of the mass term.  Then the potential would change to this, just like the two ... 13:58: ... terms in the Lagrangian, which is weird   because those are mass terms - except  neither the original gauge boson nor ... 14:54: ... everywhere refuses to cancel  out in the Lagrangian, giving us our mass ... 15:06: ... by   3 of the 4 electroweak gauge bosons. Those gain  mass and become the two W and one Z bosons of the   weak ... 16:02: ... time. But what about   this new measurement of the W boson mass? Mass  results from interaction with the Higgs field,   ... 08:09: ... That self-interaction is what leads to the   property of mass. Gauge fields shouldn’t interact  with themselves, so shouldn’t have a ... 16:02: ... time. But what about   this new measurement of the W boson mass? Mass  results from interaction with the Higgs field,   but also all ... 15:06: ... on through the mire of their coupling  with the Higgs field. Their mass shortened   their lifespans, and so enormously reduces their  range, weakening ... 14:54: ... everywhere refuses to cancel  out in the Lagrangian, giving us our mass term. ... 10:23: ... change. We’re going   to switch the sign in front of the mass term.  Then the potential would change to this, just like the two valleys we ... 13:58: ... terms in the Lagrangian, which is weird   because those are mass terms - except  neither the original gauge boson nor the   ... 04:08: ... I mentioned, pretty hefty. That’s a huge  deal breaker actually - massive bosons break gauge   symmetries. According to something ... 05:38: ... one more long-shot clue. I said  that massive bosons break the gauge   symmetry. But what if that’s okay? ... 08:09: ... particular Lagrangian describes a simple  quantum field made of massive particles which   interact with each other. Let me talk you ... 10:23: ... this potential doesn’t give us massive gauge  bosons. Let’s make a slight change. We’re going   ... 04:08: ... I mentioned, pretty hefty. That’s a huge  deal breaker actually - massive bosons break gauge   symmetries. According to something ... 05:38: ... one more long-shot clue. I said  that massive bosons break the gauge   symmetry. But what if that’s okay? ... 08:09: ... particular Lagrangian describes a simple  quantum field made of massive particles which   interact with each other. Let me talk you ... 10:23: ... this potential doesn’t give us massive gauge  bosons. Let’s make a slight change. We’re going   ... 04:08: ... I mentioned, pretty hefty. That’s a huge  deal breaker actually - massive bosons break gauge   symmetries. According to something called  ... 05:38: ... one more long-shot clue. I said  that massive bosons break the gauge   symmetry. But what if that’s okay? We’ve ... 04:08: ... I mentioned, pretty hefty. That’s a huge  deal breaker actually - massive bosons break gauge   symmetries. According to something called  ... 05:38: ... one more long-shot clue. I said  that massive bosons break the gauge   symmetry. But what if that’s okay? We’ve ... 10:23: ... this potential doesn’t give us massive gauge  bosons. Let’s make a slight change. We’re going   to switch ... 08:09: ... particular Lagrangian describes a simple  quantum field made of massive particles which   interact with each other. Let me talk you ... 11:56: ... is called a non-zero   vacuum expectation value. The original massive  particles of the field now oscillate in the   radial ... 04:08: ... far so good except that the predicted particles  are massless, while the real weak force bosons   are, as I mentioned, pretty ... 04:37: ... and the three weak force bosons, but   the latter are still massless, and the resulting  charges are completely unconnected to each ... 09:59: ... need any minimum energy to oscillate,   so the gauge boson is massless. ... 15:06: ... weak interaction. The fourth boson manages to escape  unscathed and massless, becoming the photon   that we know and love. It flew free of ... 12:26: ... The resulting particle is called a  Goldstone boson and it’s massless   because the valley is flat - there’s no energy  differential. ... 16:02: ... But what about   this new measurement of the W boson mass? Mass  results from interaction with the Higgs field,   but also all ... 00:10: ... why do we care? Because  understanding why this particle even has mass   was one of the most important breakthroughs in our understanding of ... 10:15: ... the other hand, the particle of  the original field needs a rest mass   energy to be able to oscillate  up and down the potential ... 16:02: ... are today. This is the Higgs mechanism. The Higgs field also gives mass   to the matter particles - the fermions -  but that’s for another ... 10:15: ... the other hand, the particle of  the original field needs a rest mass   energy to be able to oscillate  up and down the potential ...
	2022-04-20: Does the Universe Create Itself? 16:56: ... the universe can't be a black hole because the difference between the masses of our largest black holes in the our universe and the whole ... 17:08: ... the black holes that we’ve observed in our universe. The gap between the masses is too enormous for it to just be some extreme outlier of the same ... 17:39: ... the way - fun fact - if you calculate the size of a black hole with the mass of our observable universe - adding together all the stars, dark ... 16:56: ... the universe can't be a black hole because the difference between the masses of our largest black holes in the our universe and the whole ... 17:08: ... the black holes that we’ve observed in our universe. The gap between the masses is too enormous for it to just be some extreme outlier of the same ...
	2022-03-30: Could The Universe Be Inside A Black Hole? 10:48: ... 1999, Stephen Hawking once showed that if a black hole is leaking its mass via Hawking radiation in perfect equilibrium with the radiation that it ...
	2022-03-23: Where Is The Center of The Universe? 02:57: His general theory of relativity explains gravity as the warping of space and time due to the presence of mass and energy. 03:03: Explains gravity as the warping of space and time due to the presence of mass and energy. 17:17: They gained different properties depending on their isospin state and on their the newly gained mass. 14:59: ... asks whether the massive tides that the Proxima planets experience might be ideal for life due to ... 16:37: Well, the big one is that the elementary particles were massless back then due to the absense of the Higgs mechansism. 18:05: It’s only equal to helicity for particles that you can’t overtake - aka light speed, massless particles.
	2022-03-16: What If Charge is NOT Fundamental? 00:07: It's as though this thing - electric charge - is as fundamental a property of an object as its mass. 00:14: Well it turns out if you dig deep enough, the fundamental-ness of charge unravels, and in many things, including mass itself, unravel with it. 00:57: It seems to just be a property that particles can have or not have - as fundamental as mass. 01:52: ... the atomic nucleus, occurring with similar numbers and almost the same mass, with the only major difference being our mysterious friend - electric ... 04:14: For example, some of these particles had very similar masses but very different electric charges, which I hope reminds you of the proton and neutron. 13:08: Which, by the way, grants mass to elementary particles - yet another supposedly “fundamental” property”. 13:20: And if mass isn't fundamental, then what is? 04:14: For example, some of these particles had very similar masses but very different electric charges, which I hope reminds you of the proton and neutron.
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 01:47: The two stars were so near and so familiar - both within 10% or so of our own Sun’s mass. 03:05: This one was barely a star at all, really, at only 12% of the Sun’s mass and only a little larger than Jupiter. 04:08: A planet-star pair mutually orbits its shared center of mass - its barycenter - which is usually deep inside the star. 06:18: Such a short orbital period, combined with the star’s mass, gave them an orbital radius for the exoplanet of around 20 times smaller than the Earth’s. 06:50: ... combined with the speed of the wobble, astronomers could calculate its mass. ... 07:47: Proxima C is much bigger than it’s earth-like neighbour, at 7 times earth’s mass. 08:02: ... prospective Proxima D is just a quarter of Earth mass and orbits once every 5 days, well inside the orbit of Proxima B. That’s ... 04:08: A planet-star pair mutually orbits its shared center of mass - its barycenter - which is usually deep inside the star. 07:03: Maybe 10-50% more massive, but almost certainly a rocky world, of the type sometimes inhabited by bipedal apes. 10:34: ... resonance besides permanent day and night would result in   massive ocean tides, assuming the exoplanet  has an ocean to be pulled and ... 11:22: ... Massive convection through the star’s body generates crazy magnetic storms, ... 07:03: Maybe 10-50% more massive, but almost certainly a rocky world, of the type sometimes inhabited by bipedal apes. 10:34: ... resonance besides permanent day and night would result in   massive ocean tides, assuming the exoplanet  has an ocean to be pulled and ... 11:22: ... Massive convection through the star’s body generates crazy magnetic storms, ... 10:34: ... resonance besides permanent day and night would result in   massive ocean tides, assuming the exoplanet  has an ocean to be pulled and ...
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 00:58: ... cosmic strings. They have subatomic   thickness but prodigious mass and they lash  through space at a close to the speed of ... 07:33: ... holds an incredible   amount of energy, which gives it the mass of the planet Mars for every 100 meters of ... 00:58: ... Higgs field and Higgs boson as giving elementary particles their masses, but we should also think of   the Higgs as a fifth fundamental ... 10:09: ... to the space-time warping effect of gravity.   When a massive object sits between  us and a distant light source, it bends ... 00:58: ... all particles. Just as with water, a  field’s inherent temperature massively changes its   behavior. For example, the force-carrying field ...
	2022-02-16: Is The Wave Function The Building Block of Reality? 09:25: ... mechanics rules when things are small, but add enough mass, and the gravity of the system will cause it to rapidly decohere into a ... 10:48: ... proportional to the size of the object. Experiments are approaching the masses necessary to make such direct measurements, but they’re not quite there ... 14:52: ... the black hole’s velocity, but also can be added to the black hole’s mass. BuzzBen’s also asks whether it’s possible to focus gravitational waves ... 16:00: ... R asks how we can know that a black hole’s mass has time to crush down to the singularity, given that time dilation ... 14:52: ... the black hole’s velocity, but also can be added to the black hole’s mass. BuzzBen’s also asks whether it’s possible to focus gravitational waves to a single ... 10:48: ... proportional to the size of the object. Experiments are approaching the masses necessary to make such direct measurements, but they’re not quite there ... 09:25: ... predicts quantum mechanics will be “gravitized.” For example, consider a massive object. General relativity says that the mass from that object will warp ...
	2022-02-10: The Nature of Space and Time AMA 00:03: ... field aditya gupta asks the following when we say a large mass bends the spacetime fabric what exactly does the fabric bend into ...
	2022-01-27: How Does Gravity Escape A Black Hole? 00:00: ... in a black hole, all of the mass is concentrated at the singularity at the very center Fact: every black ... 02:31: Now you can’t just erase mass, but let’s pretend that you can for the sake of argument. 02:56: ... gravity travels at the speed of light, and all of the mass of a black hole is hidden beneath the event horizon, how does its ... 03:34: In GR, the gravitational field - the curvature of spacetime - has an independent existence to the mass that causes it. 03:54: ... space around a black hole doesn’t need to know about the mass of the central singularity - it only needs to know what the space next ... 04:02: There’s this old analogy of space as a sheet of rubber stretched by a heavy mass. 08:54: To experience the gravitational effect of a massive object, the information about the presence of that mass does have to be able to reach you. 09:03: We have to be able to “see” that mass, at least in principle. 09:06: And it might surprise you to learn that you actually CAN see the mass of black hole. 09:12: ... present mass of a black hole is hidden below the event horizon, but we can see its ... 10:01: So we can still “see” the mass of a black hole - it’s imprinted on the event horizon. 10:06: ... or by virtual gravitons, we maintain a causal connection to the mass that generated that gravitational ... 11:09: In a black hole, where is the mass? 11:13: A simplistic view says that it’s at the singularity - but that’s not the mass that you interact with. 11:18: You interact with the local curvature of spacetime, which is produced by the past mass, which from your point of view is on the event horizon. 11:27: ... fact the whole idea of mass is poorly defined in general relativity in part because the ... 11:37: To get a consistent definition for mass you need to integrate - add up - the contributions to infinite distance from the black hole. 11:45: By that definition the mass of a black hole is everywhere - so it’s not surprising that it can escape the horizon. 12:00: ... crushed into an infinitesimal point, you can rest assured that your own mass will continue to exert its gravitational influence on exterior regions ... 04:14: ... rubber at any one point in the sheet doesn’t know about the massive object - it’s being stretched only by the pull of neighboring patches of ... 04:24: ... a stretching spacetime, we can think about space as flowing towards the massive ... 08:54: To experience the gravitational effect of a massive object, the information about the presence of that mass does have to be able to reach you. 04:14: ... rubber at any one point in the sheet doesn’t know about the massive object - it’s being stretched only by the pull of neighboring patches of ... 04:24: ... a stretching spacetime, we can think about space as flowing towards the massive ... 08:54: To experience the gravitational effect of a massive object, the information about the presence of that mass does have to be able to reach you. 04:14: ... rubber at any one point in the sheet doesn’t know about the massive object - it’s being stretched only by the pull of neighboring patches of ... 04:24: ... a stretching spacetime, we can think about space as flowing towards the massive object. ... 08:54: To experience the gravitational effect of a massive object, the information about the presence of that mass does have to be able to reach you. 04:14: ... rubber at any one point in the sheet doesn’t know about the massive object - it’s being stretched only by the pull of neighboring patches of ...
	2022-01-19: How To Build The Universe in a Computer 02:56: ... to write down equations describing the trajectories of a pair of massive bodies moving in each other’s gravitational ...
	2022-01-12: How To Simulate The Universe With DFT 15:31: But the narrow column carved by the black hole has a mass much lower than the black hole itself, so it doesn’t slow down much. 19:24: As in the rest masses of entire planets.
	2021-12-29: How to Find ALIEN Dyson Spheres 06:47: If you know the mass of such a star, you can predict its size, its temperature, its brightness, its lifespan, and so on. 11:54: It would be incredibly difficult to detect such an object around a low mass star if it’s on the other side of the galaxy. 10:01: ... infrared, time and again they came up short. But the search has expanded massively. One of the latest efforts led by Swedish astronomer Erik Zackrisson ... 13:40: The discovery of a single alien megastructure of any sort would massively change the way we think about our place in the universe. 10:01: ... infrared, time and again they came up short. But the search has expanded massively. One of the latest efforts led by Swedish astronomer Erik Zackrisson ... 13:40: The discovery of a single alien megastructure of any sort would massively change the way we think about our place in the universe.
	2021-12-20: What Happens If A Black Hole Hits Earth? 00:29: ... Earth to cause trouble here. We know there are plenty of these “stellar mass” black holes wandering the galaxy that we don’t see - but the chance of ... 02:10: ... been created in such stupendous numbers that they account for 86% of the mass of the universe, and are therefore an explanation for dark ... 02:27: ... on when they formed, PBHs could have virtually any mass - from tiny ‘micro’ black holes all the way up to the supermassive black ... 03:00: ... several other clever methods, has allowed us to pretty much rule out all masses greater than about 10^19 kilograms - or around 15% the mass of our Moon. ... 03:25: ... leaves a small and very contentious window of possible masses, comparable to the masses of large asteroids. Black holes this big don’t ... 05:13: ... talk specifics. We’ll say our black hole has the mass of the Martian moon phobos - 10^16 kg like a large asteroid. That gives ... 06:35: ... black hole the faster it can feed, but there’s a limit defined by its mass. ... 07:05: ... very low. For an asteroid-mass black hole at the absolute top end of our mass range, the cloud of plasma is barely microns in size, but it still ... 08:41: ... devastation is only for black holes at the top end of our mass range. The smaller the black hole, the more likely it is we’d miss it as ... 09:03: ... waves would reach all points on the Earth’s surface. Even at the lowest mass possible for a primordial black hole it will produce the equivalent of a ... 09:24: ... of the trouble is that these impacts would be rare. For the smallest PBH masses, there may only be one black hole hitting the earth every million years. ... 12:44: ... primordial black holes are a thing, and it would tell us about their masses. ... 02:27: ... on when they formed, PBHs could have virtually any mass - from tiny ‘micro’ black holes all the way up to the supermassive black ... 00:29: ... Earth to cause trouble here. We know there are plenty of these “stellar mass” black holes wandering the galaxy that we don’t see - but the chance of one ... 07:05: ... very low. For an asteroid-mass black hole at the absolute top end of our mass range, the cloud of plasma is barely microns in size, but it still shines with ... 08:41: ... devastation is only for black holes at the top end of our mass range. The smaller the black hole, the more likely it is we’d miss it as it ... 02:27: ... have managed to systematically rule out most of the windows of possible masses if PBHs are to account for most of the dark ... 03:00: ... several other clever methods, has allowed us to pretty much rule out all masses greater than about 10^19 kilograms - or around 15% the mass of our Moon. ... 03:25: ... leaves a small and very contentious window of possible masses, comparable to the masses of large asteroids. Black holes this big don’t ... 09:24: ... of the trouble is that these impacts would be rare. For the smallest PBH masses, there may only be one black hole hitting the earth every million years. ... 12:44: ... primordial black holes are a thing, and it would tell us about their masses. ... 03:25: ... leaves a small and very contentious window of possible masses, comparable to the masses of large asteroids. Black holes this big don’t devour ... 03:00: ... several other clever methods, has allowed us to pretty much rule out all masses greater than about 10^19 kilograms - or around 15% the mass of our Moon. ... 07:40: ... this description is not too different from the Tunguska event- a massive impact that occurred in 1908 in the middle of Siberia. Witnesses ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... much focused right now on gravitational lensing so using the fact that massive bodies bend the paths of light according to einstein's theory of ...
	2021-11-17: Are Black Holes Actually Fuzzballs? 01:14: ... only properties that we can observe from outside a black hole are its mass, electric charge, and angular ... 01:34: ... we get a prodigiously large number - 10^10^77 bits for a black hole the mass of our ... 02:56: The no-hair theorem says that there’s no information beyond charge, mass and spin that’s observable above the event horizon. 03:17: ... should be completely random, and so leaks away the black hole’s mass without any of the information that went into building the black ... 06:01: ... hole singularity, because instead of collapsing all of a black hole’s mass into a single point, it gets distributed around the ring structure of ... 01:14: ... only properties that we can observe from outside a black hole are its mass, electric charge, and angular ... 10:50: Light trying to escape would still be massively redshifted - sapped of energy by the gravitational field - rendering the object effectively black. 10:58: It would still cause massive gravitational lensing, time dilation, etc. 10:50: Light trying to escape would still be massively redshifted - sapped of energy by the gravitational field - rendering the object effectively black.
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 00:24: ... - assuming  they are held together by the gravity of their visible mass ... 00:42: ... lenses - when more distant light sources are warped by an intervening mass. ... 00:57: It sure looks like 80% of the mass in the universe is completely invisible to us. 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass. 01:29: So … the mass could be wrong. 02:02: ... gravitational field drops off with the square of distance from  the mass producing that ... 02:32: ... matter is supposed to add extra mass that’s more evenly distributed through galaxies, strengthening the ... 04:08: If you tune the modification right you recover  the observed rotation curves for spiral galaxies very nicely without the need for extra mass. 05:30: Now you might think that cutting down the invisible mass requirement by 80% is pretty good - and it is helpful to be honest. 02:02: ... gravitational field drops off with the square of distance from  the mass producing that ... 05:30: Now you might think that cutting down the invisible mass requirement by 80% is pretty good - and it is helpful to be honest.
	2021-11-02: Is ACTION The Most Fundamental Property in Physics? 08:06: ... proper time becomes kinetic minus potential energy for objects with mass, but for objects without mass, like light, proper time and time are the ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 15:23: Erik says that if magnetic monopoles are massive enough to collapse the early univeres, wouldn’t we only find them inside black holes?
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 11:47: They should also be very massive - quadrillions of times the mass of the proton - and so should have quickly recollapsed the universe. 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles. 11:12: ... predict these magnetic monopoles, and that they should be A) very massive, and B) should form spontaneously in extremely high-energy environments ... 11:47: They should also be very massive - quadrillions of times the mass of the proton - and so should have quickly recollapsed the universe. 16:32: ... example, if a collapsing stellar core is massive enough it smashes through the degeneracy pressure that supports white ... 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles. 11:12: ... predict these magnetic monopoles, and that they should be A) very massive, and B) should form spontaneously in extremely high-energy environments ... 11:47: They should also be very massive - quadrillions of times the mass of the proton - and so should have quickly recollapsed the universe. 16:32: ... example, if a collapsing stellar core is massive enough it smashes through the degeneracy pressure that supports white ... 11:47: They should also be very massive - quadrillions of times the mass of the proton - and so should have quickly recollapsed the universe. 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles.
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 04:04: ... inside  of a white dwarf - the dead core of a lower   mass star like our Sun. The plasma is crushed so tight that electrons ... 13:06: ... matter from a binary partner star.   Its mass is growing and at some point soon it’ll form an inescapable event ... 04:04: ... inside  of a white dwarf - the dead core of a lower   mass star like our Sun. The plasma is crushed so tight that electrons are on ... 00:25: ... these things before - about how they form from the dead cores of massive stars,   left over after supernova explosions. We’ve  ...
	2021-09-07: First Detection of Light from Behind a Black Hole 03:13: ... holes in the universe - anything more than a million or so times the mass of the ... 11:33: ... into a lot more detail than this - lots of good stuff like measuring the mass of the black hole - 30 million Suns - to verifying Einstein’s general ...
	2021-08-18: How Vacuum Decay Would Destroy The Universe 03:11: ... of  Higgsiness. Most elementary particles that have   mass gain their mass due to interactions with this ubiquitous field. I ... 08:30: ... Higgs field gives elementary particles their   masses. Those masses depend on the energy in the field - the so-called ... 09:38: ... precise measurements of the particles  that gain their mass from the Higgs.   The most important are the Higgs ... 03:11: ... of  Higgsiness. Most elementary particles that have   mass gain their mass due to interactions with this ubiquitous field. I go ... 08:30: ... Higgs field gives elementary particles their   masses. Those masses depend on the energy in the field - the so-called ... 09:38: ... the most massive elementary particle. And our measurements of these masses tell us that … we are probably in the false vacuum - but ... 08:30: ... Higgs field gives elementary particles their   masses. Those masses depend on the energy in the field - the so-called vacuum ... 03:11: ... this ubiquitous field. I go into all the detail of the   mass-granting power of the Higgs mechanism in a previous video. For today, all ... 09:38: ... itself as well as the top quark, which is   the most massive elementary particle. And our measurements of these masses tell us ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 15:46: ... is that the partner goes on to explode as a supernova. But the mass transfer onto the white dwarf actually makes this less likely because ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 01:45: ... are white dwarfs, the final fate of any star less than 8 or so times the mass of the ... 05:51: ... comparison, a white dwarf the mass of our sun would be around the size of the earth, this new guy is barely ... 06:04: ... good to know the size of a white dwarf is that it also tells you its mass. Here we need to learn something that’s weird about all white dwarfs, not ... 07:24: ... happens if you add more mass to a white dwarf? First let’s think about what happens when you add mass ... 08:05: ... mechanics, it was found that it must weigh in at 1.32 times the Sun’s mass. And that’s a lot, at least for a white dwarf. We’ve known for some time ... 08:29: ... hole. But If you already have a white dwarf and then slowly add more mass it’ll explode as a type 1a ... 08:48: ... is below this mass limit, so it has avoided destruction - so far. We’ll come back to its ... 09:51: ... a pair of white dwarfs merge, two things might happen - either their mass adds up to more than the Chandrasekhar limit and bad things happen that ... 10:37: ... when a stellar remnant exceeds the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for ... 13:41: ... a moon-sized, highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each other. It teeters on the edge of ... 14:52: ... fields stay untangled, your electrons be ever degenerate, and may your mass remain always ... 09:51: ... a pair of white dwarfs merge, two things might happen - either their mass adds up to more than the Chandrasekhar limit and bad things happen that I’ll ... 08:29: ... hole. But If you already have a white dwarf and then slowly add more mass it’ll explode as a type 1a ... 08:48: ... is below this mass limit, so it has avoided destruction - so far. We’ll come back to its final, ... 14:52: ... fields stay untangled, your electrons be ever degenerate, and may your mass remain always ... 13:41: ... a moon-sized, highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each other. It teeters on the edge of explosion, ... 08:05: ... some time that the absolute maximum mass for a white dwarf is 1.44 solar masses - the Chandrasekhar ... 10:37: ... when a stellar remnant exceeds the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for ... 08:05: ... some time that the absolute maximum mass for a white dwarf is 1.44 solar masses - the Chandrasekhar ... 10:37: ... when a stellar remnant exceeds the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for ... 00:47: ... a white dwarf that, at first glance, looked suspicious - a bit too massive and spinning a bit too fast. That spin was seen in its rapid but ... 01:45: ... dwarfs - or at least, what we thought we knew. When all but the most massive stars end their lives, they blast off their outer layers in their final ... 06:04: ... not just Zee. We normally think about objects getting bigger the more massive they ... 07:24: ... have enough pressure to resist the extra gravity. As a result, the more massive the white dwarf, the smaller in ... 08:05: ... if Zee is the smallest known white dwarf it must also be the most massive. Doing a little quantum mechanics, it was found that it must weigh in at ... 08:48: ... review the evidence. We have one weird white dwarf - it’s extremely massive and compact - but that’s not so strange in itself. The strange part is ... 10:37: ... the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for accreting white dwarfs. So what ... 00:47: ... a white dwarf that, at first glance, looked suspicious - a bit too massive and spinning a bit too fast. That spin was seen in its rapid but ... 01:45: ... dwarfs - or at least, what we thought we knew. When all but the most massive stars end their lives, they blast off their outer layers in their final ... 06:04: ... not just Zee. We normally think about objects getting bigger the more massive they ... 07:24: ... have enough pressure to resist the extra gravity. As a result, the more massive the white dwarf, the smaller in ... 08:05: ... if Zee is the smallest known white dwarf it must also be the most massive. Doing a little quantum mechanics, it was found that it must weigh in at ... 08:48: ... review the evidence. We have one weird white dwarf - it’s extremely massive and compact - but that’s not so strange in itself. The strange part is ... 10:37: ... the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for accreting white dwarfs. So what ... 01:45: ... dwarfs - or at least, what we thought we knew. When all but the most massive stars end their lives, they blast off their outer layers in their final fits ... 10:37: ... the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for accreting white dwarfs. So what happens ...
	2021-07-21: How Magnetism Shapes The Universe 04:39: These coronal mass ejections join the solar wind. 18:15: That could massively cut down the number of worlds to only the most probable.
	2021-07-07: Electrons DO NOT Spin 01:26: ... than simple rotation - it’s a quantum property of particles, like mass or the various charges. But it doesn’t just cause magnets to move in ... 15:31: ... the different  ways they could move. The low gravitational entropy massively outweighed the matter entropy,  so entropy was low. That smoothness ...
	2021-06-23: How Quantum Entanglement Creates Entropy 01:02: ... in the same way. Instead, that molecule has a   velocity and a mass and so on, which define how it bounces off the walls or other ...
	2021-06-16: Can Space Be Infinitely Divided? 05:45: ... now adding two key ideas from Einstein:   first that mass and energy are equivalent, as expressed by the most famous equation ... 06:02: ... enclosed in a system a photon   creates what we call effective mass, according to Einstein’s famous equation. The resulting   ... 06:39: ... is. Space is stretched   by a factor equal to the effective mass times the gravitational constant divided by c^2.   Let’s ... 07:48: ... than one-Planck-length.   But that photon has enough effective mass to produce a black hole with a Planck-length event   ... 08:37: ... we need to be able to say that all of the  electron’s mass is within a certain volume.   So defining position means ... 06:02: ... enclosed in a system a photon   creates what we call effective mass, according to Einstein’s famous equation. The resulting   gravitational ... 06:39: ... is. Space is stretched   by a factor equal to the effective mass times the gravitational constant divided by c^2.   Let’s replace the ... 07:48: ... than one-Planck-length.   But that photon has enough effective mass to produce a black hole with a Planck-length event   horizon - so any ... 08:37: ... the uncertainty in energy is about equal to the entire mass-energy of the electron. At that point,   you can’t say there’s just ...
	2021-06-09: Are We Running Out of Space Above Earth? 15:11: Johanna Mueller never realized that the Planck mass is such a huge thing. 15:24: But the planck mass defines the mass of a black hole one Planck length in radius, and remember, black holes are massive! 15:58: This is what makes them the perfect candidate for WIMPS - the weakly interacting massive objects that may explain dark matter. 15:24: But the planck mass defines the mass of a black hole one Planck length in radius, and remember, black holes are massive! 15:58: This is what makes them the perfect candidate for WIMPS - the weakly interacting massive objects that may explain dark matter.
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 01:01: He showed that black holes must radiate, and so slowly leak away their mass in what we now call Hawking radiation. 03:25: But as the black hole shrinks in mass and in size, its Hawking radiation also decreases in wavelength - but it increases in energy. 05:49: You no longer have a smooth, statistical spectrum to your thermal radiation - the black hole will leak its remaining mass in sudden, discrete steps. 05:59: And at some point, there may be no allowed transitions that can take away the last of the black hole’s mass. 06:20: In other words, when you get to the point where a single photon would take away the rest of the black hole’s mass. 06:31: This would be when the black hole’s mass is around 20 micrograms - what we call the Planck mass. 07:29: The smallest such black holes will take something like 10^66 years to Hawking-radiate their entire mass away. 07:51: A black hole with a mass of a billion tons or lower could have decayed to a relic by now - and fortunately there’s a way to make those. 08:03: ... produce enormous numbers of black holes, potentially of a wide range of masses. ... 08:35: And you’d need a lot to say the least because dark matter makes up 80% of the mass of the universe. 10:52: Just one Planck relic per 30km cube, and that’s enough to make up most of the mass in the universe. 08:03: ... produce enormous numbers of black holes, potentially of a wide range of masses. ... 03:02: For the black hole left behind when a massive star dies, the event horizon is several kilometers in radius. 07:22: The only way to make black holes in the modern universe is in the deaths of massive stars. 03:02: For the black hole left behind when a massive star dies, the event horizon is several kilometers in radius. 07:22: The only way to make black holes in the modern universe is in the deaths of massive stars. 03:02: For the black hole left behind when a massive star dies, the event horizon is several kilometers in radius. 07:22: The only way to make black holes in the modern universe is in the deaths of massive stars.
	2021-05-19: Breaking The Heisenberg Uncertainty Principle 10:03: ... in other systems like entangled atomic clocks, which may one day massively enhance the precision of our GPS ...
	2021-05-11: How To Know If It's Aliens 16:32: ... all the properties to qualify it as a WIMP - namely wearing interacting, massive, and particle-like. Fun fact: Einstein, along with Nathan Rosen, tried to ...
	2021-04-21: The NEW Warp Drive Possibilities 02:30: His special theory of relativity just says that it takes infinite energy to accelerate anything with positive mass all the way to light speed. 04:01: ... to solve these equations we input a physically possible distribution of mass, energy, on the right side and it spits out the spacetime geometry on the ... 04:59: ... people talk about the drive requiring negative mass - also called exotic matter - and yeah, that would do the trick too - ... 10:47: It’s hard to see how packing that much mass into these strips would NOT create a black hole. 14:18: The probability that a particle will interact with other massive virtual particles is proportional to the square of that particle’s own mass. 14:26: At nearly 17 times the mass of the muon, the tau should be even more sensitive to unknown particles. 04:59: ... people talk about the drive requiring negative mass - also called exotic matter - and yeah, that would do the trick too - and ... 04:01: ... to solve these equations we input a physically possible distribution of mass, energy, on the right side and it spits out the spacetime geometry on the ... 04:23: You can do this with any geometry, but almost every geometry will produce an impossible mass-energy distribution. 02:38: That effectively means that it’s impossible to observe a massive object cross this speed barrier. 14:18: The probability that a particle will interact with other massive virtual particles is proportional to the square of that particle’s own mass. 02:38: That effectively means that it’s impossible to observe a massive object cross this speed barrier. 14:18: The probability that a particle will interact with other massive virtual particles is proportional to the square of that particle’s own mass. 02:38: That effectively means that it’s impossible to observe a massive object cross this speed barrier. 14:18: The probability that a particle will interact with other massive virtual particles is proportional to the square of that particle’s own mass.
	2021-04-13: What If Dark Matter Is Just Black Holes? 00:18: 80% of the mass of our universe is completely invisible to us - its existence only revealed through its immense gravitational influence. 01:39: ... dark matter makes up roughly 80% of the mass of the universe, but it’s much more spread out than regular matter - ... 01:53: ... be dark matter they’d need to be abundant enough to make up all of this mass, and they’d need to be spread out in the same way that dark matter ... 02:15: The main remaining variable is the mass of the individual black holes. 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 02:32: Any given study is sensitive to a particular range of black hole masses. 02:37: If a study doesn’t find enough of black holes in that range, then that mass range is ruled out as a main contributor to dark matter. 02:53: ... we’re going to go through the mass spectrum of black holes, and close one window after another - we’ll see ... 03:06: ... before we start eliminating specific black holes masses, let’s rule out an entire class of black holes. In face we're going to ... 05:13: ... those black holes should have all formed at around the same mass - but that mass depends on the details of the state of the early ... 05:28: Because of this, to really falsify the primordial black hole as dark matter hypothesis, we need to rule out this entire mass range. 05:37: We’ll begin with the extreme ends of the mass spectrum - those are easy. 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 06:00: At the opposite end of the mass spectrum we have the black holes under a billion tons or around the mass of a small mountain. 06:20: ... dark matter to be made of black holes with masses around that of a larger asteroid or small moon, we’d need truly ... 07:30: Probably no more than a few percent of the dark matter mass can be from these micro black holes. 07:36: Ok, let’s move up the black hole mass spectrum to masses around that of a planet. 07:44: ... a compact mass like a black hole passes in front of a distant light source, the warped ... 07:58: ... whether the lensing object is a black hole or some other dark compact mass like a brown dwarf star, neutron star, Dyson sphere or a cluster of ... 08:52: ... has allowed us to rule out MACHOs between roughly the moon’s mass to 10 or so times the mass of the Sun as a main contributor to dark ... 09:07: ... have found enough microlensing events to suggest that 20% of the mass of the Milky Way halo may be dark, compact objects with the masses of a ... 09:30: So far we’ve mostly ruled out black holes around the Sun’s mass or lower as an explanation for dark matter. 09:37: ... black holes are tricky, because you need fewer of them to make up the mass of dark matter - which means they're less likely to spotted through ... 09:46: ... holes trickle to the center of our galaxy, but there’s an intermediate mass range from tens to thousands of solar masses that could still be ... 10:01: ... galaxies are so small and dense that even black holes with tens of solar masses should have trickled to the center by now, and in the process flung less ... 10:11: ... 4% of the dark matter could be black holes of tens to thousands of solar masses. ... 10:20: ... - if there were lots of black holes of several tens times the Sun’s mass then these binaries would long ago have been torn apart by close ... 10:37: We have some evidence ruling out most of the black hole mass spectrum as the main source of dark matter. 05:13: ... those black holes should have all formed at around the same mass - but that mass depends on the details of the state of the early universe, ... 02:37: If a study doesn’t find enough of black holes in that range, then that mass range is ruled out as a main contributor to dark matter. 05:28: Because of this, to really falsify the primordial black hole as dark matter hypothesis, we need to rule out this entire mass range. 09:46: ... holes trickle to the center of our galaxy, but there’s an intermediate mass range from tens to thousands of solar masses that could still be abundant ... 02:53: ... we’re going to go through the mass spectrum of black holes, and close one window after another - we’ll see at the ... 05:37: We’ll begin with the extreme ends of the mass spectrum - those are easy. 06:00: At the opposite end of the mass spectrum we have the black holes under a billion tons or around the mass of a small mountain. 07:36: Ok, let’s move up the black hole mass spectrum to masses around that of a planet. 10:37: We have some evidence ruling out most of the black hole mass spectrum as the main source of dark matter. 05:37: We’ll begin with the extreme ends of the mass spectrum - those are easy. 02:32: Any given study is sensitive to a particular range of black hole masses. 03:06: ... before we start eliminating specific black holes masses, let’s rule out an entire class of black holes. In face we're going to ... 06:20: ... dark matter to be made of black holes with masses around that of a larger asteroid or small moon, we’d need truly ... 07:36: Ok, let’s move up the black hole mass spectrum to masses around that of a planet. 09:07: ... of the mass of the Milky Way halo may be dark, compact objects with the masses of a small ... 09:46: ... but there’s an intermediate mass range from tens to thousands of solar masses that could still be abundant throughout the Milky ... 10:01: ... galaxies are so small and dense that even black holes with tens of solar masses should have trickled to the center by now, and in the process flung less ... 10:11: ... 4% of the dark matter could be black holes of tens to thousands of solar masses. ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 03:16: We know black holes form from the remaining cores of the most massive stars, after they explode as supernovae. 05:03: ... much stronger at earlier times and perhaps strong enough that the most massive of them would have collapsed into black ... 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 07:58: ... Dyson sphere or a cluster of Reaper capital ships - as long as they’re massive, compact, and dwell in vast numbers throughout the halo of the Milky Way, ... 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 09:46: ... I mentioned, the most massive black holes trickle to the center of our galaxy, but there’s an ... 10:01: ... should have trickled to the center by now, and in the process flung less massive stars into higher ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 03:16: We know black holes form from the remaining cores of the most massive stars, after they explode as supernovae. 05:03: ... much stronger at earlier times and perhaps strong enough that the most massive of them would have collapsed into black ... 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 07:58: ... Dyson sphere or a cluster of Reaper capital ships - as long as they’re massive, compact, and dwell in vast numbers throughout the halo of the Milky Way, ... 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 09:46: ... I mentioned, the most massive black holes trickle to the center of our galaxy, but there’s an ... 10:01: ... should have trickled to the center by now, and in the process flung less massive stars into higher ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 09:46: ... I mentioned, the most massive black holes trickle to the center of our galaxy, but there’s an intermediate ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 05:43: The most massive black holes in the universe weigh in at millions to billions of times the mass of our Sun. 09:46: ... I mentioned, the most massive black holes trickle to the center of our galaxy, but there’s an intermediate mass ... 07:58: ... Dyson sphere or a cluster of Reaper capital ships - as long as they’re massive, compact, and dwell in vast numbers throughout the halo of the Milky Way, watching ... 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 03:16: We know black holes form from the remaining cores of the most massive stars, after they explode as supernovae. 10:01: ... should have trickled to the center by now, and in the process flung less massive stars into higher ...
	2021-04-07: Why the Muon g-2 Results Are So Exciting! 02:38: The muon, is a close cousin to the electron identical in all properties besides its heavier mass. 03:43: For a rotating charge, that depends on the objects rate of rotation, or angular momentum, it's charge and it's mass. 04:00: An electron also has a dipole field and a dipole moment which depends on the electron spin charge and mass. 08:19: The probability of interaction between a particle and some massive virtual particle is proportional to mass squared. 08:16: The muon is 200 times more massive than the electron. 08:19: The probability of interaction between a particle and some massive virtual particle is proportional to mass squared. 08:16: The muon is 200 times more massive than the electron. 08:19: The probability of interaction between a particle and some massive virtual particle is proportional to mass squared.
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 15:21: ... determined by the so-called chirp-mass, which is a combination of the masses of both black ... 15:32: But that chirp mass also determines the power that was radiated in gravitational waves during the inspiral. 15:21: ... determined by the so-called chirp-mass, which is a combination of the masses of both black ...
	2021-03-16: The NEW Crisis in Cosmology 00:22: ... But just recently, one of these methods  received a massive refinement due to the   Gaia mission and its unprecedented ... 10:40: ... is  gravitational lensing - the bending of   light around massive objects due  to their warping of spacetime.   One ... 13:38: ... this notion gets stated without much justification. The idea that massive objects   travel through time at the speed of light its just ... 00:22: ... But just recently, one of these methods  received a massive refinement due to the   Gaia mission and its unprecedented ... 10:40: ... is  gravitational lensing - the bending of   light around massive objects due  to their warping of spacetime.   One ... 13:38: ... this notion gets stated without much justification. The idea that massive objects   travel through time at the speed of light its just ... 10:40: ... is  gravitational lensing - the bending of   light around massive objects due  to their warping of spacetime.   One manifestation ... 13:38: ... this notion gets stated without much justification. The idea that massive objects   travel through time at the speed of light its just one way to interpret ... 00:22: ... But just recently, one of these methods  received a massive refinement due to the   Gaia mission and its unprecedented survey of ... 10:40: ... surveys set to discover thousands of new lenses that should massively improve this ...
	2021-03-09: How Does Gravity Affect Light? 01:38: ... that what we experience as the force of gravity is mostly due to the way mass warps the flow of ... 01:47: But the photon doesn’t experience the flow of time - it doesn’t even have any mass. 04:47: ... the bizarre thing is that the density of mass required to produce this infinite redshift is exactly the same as is ... 01:38: ... that what we experience as the force of gravity is mostly due to the way mass warps the flow of ... 00:38: ... a particle of light gripped by the gravitational field of a sufficiently massive star would slow down, stop, and fall back - and so was the first to ... 00:52: ... a particle of light would be deflected in its path as it passed near a massive ... 01:10: They assumed that light could be slowed down, and that light experiences a force of gravity in the same way that a massive object does. 06:31: To get technical: any massive object has a component of its 4-dimensional spacetime velocity - its 4-velocity in the time direction. 11:21: Einstein used this approach to calculate the deflection expected when light passes a massive object. 00:38: ... a particle of light gripped by the gravitational field of a sufficiently massive star would slow down, stop, and fall back - and so was the first to ... 00:52: ... a particle of light would be deflected in its path as it passed near a massive ... 01:10: They assumed that light could be slowed down, and that light experiences a force of gravity in the same way that a massive object does. 06:31: To get technical: any massive object has a component of its 4-dimensional spacetime velocity - its 4-velocity in the time direction. 11:21: Einstein used this approach to calculate the deflection expected when light passes a massive object. 00:52: ... a particle of light would be deflected in its path as it passed near a massive object. ... 01:10: They assumed that light could be slowed down, and that light experiences a force of gravity in the same way that a massive object does. 06:31: To get technical: any massive object has a component of its 4-dimensional spacetime velocity - its 4-velocity in the time direction. 11:21: Einstein used this approach to calculate the deflection expected when light passes a massive object. 00:38: ... a particle of light gripped by the gravitational field of a sufficiently massive star would slow down, stop, and fall back - and so was the first to predict ... 06:57: ... if we imagine light as a perfectly narrow ray, or even as a massless, timeless particle, none of our intuitive explanations say that it should ...
	2021-02-24: Does Time Cause Gravity? 02:33: We know that the presence of mass and energy warp spacetime - and the most intense part of that warping is in time - our gravitational time dilation. 03:16: It’s almost like Earth’s mass creates a drag on the flow of time around it. 05:22: ... light through space - obviously enough - and we know that nothing with mass can reach that speed traveling through ... 05:31: But if we interpret time as a dimension like space, then a stationary mass really is moving at the fastest possible speed in the temporal direction. 06:29: ... see the same favorable exchange when we try to convert mass into energy via Einstein’s most famous equation, E=mc^2 - the speed of ... 03:16: It’s almost like Earth’s mass creates a drag on the flow of time around it. 02:27: OK, now let’s add a second object - something nice and massive … the planet Earth will do. 05:44: The 4-velocity of a massive object is pointed almost entirely in the time direction. 02:27: OK, now let’s add a second object - something nice and massive … the planet Earth will do. 05:44: The 4-velocity of a massive object is pointed almost entirely in the time direction. 05:57: ... the time direction into space - although technically photons and other massless particles don’t have a 4-velocity, which is defined according to the ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... are expected to be produced in a few different ways black holes with masses of millions to billions of suns live in the cores of most galaxies these ...
	2021-02-10: How Does Gravity Warp the Flow of Time? 01:37: Mass and energy change the lengths of rulers and the speeds of clocks - and somehow those changes lead to objects being attracted to each other. 04:14: And, in fact, to any matter - anything that can experience time, which in practice means anything with mass. 03:57: This is a simple pair of perfectly reflective, massless mirrors between which bounces a single photon of light.
	2021-01-26: Is Dark Matter Made of Particles? 00:07: The particle or particles of the dark sector make up the vast majority of the mass in the universe - so to them, you are the ghostly one. 02:45: The force of gravity is a sort of lingua franca, a common language that every particle with mass can speak. 03:27: ... matter can’t have charge but it must have mass because the only thing we’ve ever actually seen dark matter do is to ... 05:41: ... model move too fast - they are “hot” - and there just isn’t enough mass in neutrinos to do the job, due to them being ridiculously ... 07:33: Axions, if they exist, would be incredibly light - maybe 1% or less the mass of the already-puny neutrino. 09:26: ... expected mass of these particles is eerily close to the mass expected for a certain ... 10:07: ... part is obvious enough - it helps if you want to make up 80% of the mass in the universe, and also slows the particle down - helps make it ... 09:26: ... expected mass of these particles is eerily close to the mass expected for a certain type of dark matter - which some would say is a point in ... 04:34: In fact, galaxies are really just shiny dustings of stars, sprinkled deep in the gravitational wells of massive reservoirs of dark matter. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 09:45: ... dark matter particle type called the WIMP, or “weakly interacting massive ... 09:59: It’s a description of what some physicists thought dark matter particles had to be like- which is to say, weakly interacting and massive. 10:07: ... massive part is obvious enough - it helps if you want to make up 80% of the mass ... 12:35: ... sector exists in parallel to this completely invisible and vastly more massive sector of dark ... 04:34: In fact, galaxies are really just shiny dustings of stars, sprinkled deep in the gravitational wells of massive reservoirs of dark matter. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 09:45: ... dark matter particle type called the WIMP, or “weakly interacting massive ... 09:59: It’s a description of what some physicists thought dark matter particles had to be like- which is to say, weakly interacting and massive. 10:07: ... massive part is obvious enough - it helps if you want to make up 80% of the mass ... 12:35: ... sector exists in parallel to this completely invisible and vastly more massive sector of dark ... 09:45: ... dark matter particle type called the WIMP, or “weakly interacting massive particle”. ... 04:34: In fact, galaxies are really just shiny dustings of stars, sprinkled deep in the gravitational wells of massive reservoirs of dark matter. 12:35: ... sector exists in parallel to this completely invisible and vastly more massive sector of dark ...
	2020-12-22: Navigating with Quantum Entanglement 03:31: This “geomagnetic” field is generated by the convective motion in Earth’s outer core - which is a churning liquid mass of white-hot nickel and iron. 13:47: ... its fuel - that’s a type 2 supernova - or the remnant of a lower mass star - a white dwarf - gains extra mass and explodes - that’s a type ... 14:34: ... stars will decay into pions and neutrinos, leaking away some of the mass of the neutron ... 13:47: ... its fuel - that’s a type 2 supernova - or the remnant of a lower mass star - a white dwarf - gains extra mass and explodes - that’s a type ...
	2020-12-15: The Supernova At The End of Time 05:49: ... could support a dead star up to a point - if that stellar remnant’s mass was too high then a new process would take ... 06:24: ... SS Pilsner, Chandra just knew that no white dwarf could exist above that mass limit - what we now call the Chandrasekhar limit. For the stellar core ... 09:56: Remember that the Chandresekhar limit gives the largest mass possible for a stellar remnant to be supported by this pressure. 10:02: It depends on the number of electrons relative to the mass of the star. 10:41: By the time the iron star is fully formed, its Chandresekhar mass has dropped from around 1.44 to less than 1.2. 10:48: times the Sun’s mass. 10:50: ... white dwarf - or now iron black dwarf - that was initially stable with a mass below the original Chandrasekhar limit could become unstable if it’s ... 06:24: ... SS Pilsner, Chandra just knew that no white dwarf could exist above that mass limit - what we now call the Chandrasekhar limit. For the stellar core left ... 10:50: ... limit could become unstable if it’s mass is greater than 1.16 solar masses. ...
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 00:47: And this dive into electroweak unification will lead us inevitably to the Higgs field and an understanding of how particles gain mass. 03:33: ... that, if they existed, these new ‘weak bosons’, W bosons, had to have mass due to the short range nature of the interaction, quite a lot of mass it ... 04:18: That requirement of the W bosons having mass was an enormous theoretical headache. 04:24: Gauge bosons should just not have mass. 08:24: But the bosons of the weak force have to have mass. 08:30: Maybe, but the whole gauge field thing seemed so promising, so it's worth asking: how can we give mass to something that seems fundamentally massless? 08:48: Adding in mass screws up those symmetries. 08:50: ... example, adding mass to a photon means adding an extra term to the electromagnetic field ... 09:01: In order for the weak force bosons to have mass, we have to willingly break the symmetry that gave us them in the first place. 11:00: That could lead to our force carriers having mass. 12:47: ... to really make this work - to give the weak force bosons their mass - we have to conclude that really these fields, these symmetries, are ... 08:48: Adding in mass screws up those symmetries. 03:48: ... short range nature of forces with massive force carriers is usually attributed to the energy-time uncertainty ... 04:33: ... as we'll see, the simple requirement that the weak force was mediated by massive particles ultimately unified the weak force with electromagnetism, and ... 11:48: ... - leaving an independent, massless s(1) field for the photon and a massive, broken SU(2) field that gives the massive weak force ... 03:48: ... short range nature of forces with massive force carriers is usually attributed to the energy-time uncertainty ... 04:33: ... as we'll see, the simple requirement that the weak force was mediated by massive particles ultimately unified the weak force with electromagnetism, and ... 11:48: ... - leaving an independent, massless s(1) field for the photon and a massive, broken SU(2) field that gives the massive weak force ... 03:48: ... short range nature of forces with massive force carriers is usually attributed to the energy-time uncertainty relation, ... 04:33: ... as we'll see, the simple requirement that the weak force was mediated by massive particles ultimately unified the weak force with electromagnetism, and revealed ... 11:48: ... field for the photon and a massive, broken SU(2) field that gives the massive weak force ... 08:08: The fields and corresponding particles produced by the pure symmetries we described are fundamentally massless. 08:30: Maybe, but the whole gauge field thing seemed so promising, so it's worth asking: how can we give mass to something that seems fundamentally massless? 08:40: The perfect masslessness of these gauge fields and bosons is a direct consequence of the perfect symmetries from which they come. 11:36: The combined SU(2)xU(1) symmetry is the electroweak field, and it has 4 massless bosons, like a well behaved symmetry should. 11:48: ... this symmetry is spontaneously broken - leaving an independent, massless s(1) field for the photon and a massive, broken SU(2) field that gives ... 11:36: The combined SU(2)xU(1) symmetry is the electroweak field, and it has 4 massless bosons, like a well behaved symmetry should. 11:48: ... this symmetry is spontaneously broken - leaving an independent, massless s(1) field for the photon and a massive, broken SU(2) field that gives the ... 08:40: The perfect masslessness of these gauge fields and bosons is a direct consequence of the perfect symmetries from which they come.
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 05:01: ... always produce this convergence. It would take negative mass or negative pressure   to cause light rays to diverge. This ... 00:34: ... they realized the possibility of a  star so massive that it would prevent   even light from escaping its surface. ...
	2020-10-05: Venus May Have Life! 01:28: Its atmosphere is 100 times the mass of Earth’s and mostly carbon dioxide.
	2020-09-21: Could Life Evolve Inside Stars? 03:04: These may have been formed soon after the Big Bang when massive phase transitions swept across the universe.
	2020-09-01: How Do We Know What Stars Are Made Of? 02:18: Harvard University in Massachusetts was already proving itself at least a little friendlier to women.
	2020-08-24: Can Future Colliders Break the Standard Model? 04:46: The existence of the Higgs confirms our explanation of how the elementary particles acquire mass - which of course we’ve covered previously. 05:25: ... gravity and the other forces, and a huge difference between the measured masses of the known particles and what we expect their masses to be from ... 05:40: The Higgs particle in particular should have an enormous mass if our Standard Model understanding is the whole picture. 05:48: The fact that the Higgs turns up at a “mere” 100 times the mass of the proton seemed to indicate that something beyond the standard model was needed. 06:02: ... quantum fields on which those particles live, eliminating most of their mass in the ... 06:54: Besides the hierarchy problem, the standard model also doesn’t explain why neutrinos have mass. 14:59: In the case of the merging black holes, you can think of space as more flowing towards the center of mass - although it’s not quite that simple. 15:53: David Kosa asks how would we describe the interaction of two merging stars of equal mass whose combined mass exceeds the Chandrashekar limit? 15:59: ... those who don't know - the Chandrashekar limit is 1.4 times the mass of the sun - it’s the maximum mass of a white dwarf before crushing ... 16:19: But what about white dwarfs that gain more mass after they form? Or that collide to have above that mass? 04:46: The existence of the Higgs confirms our explanation of how the elementary particles acquire mass - which of course we’ve covered previously. 14:59: In the case of the merging black holes, you can think of space as more flowing towards the center of mass - although it’s not quite that simple. 15:53: David Kosa asks how would we describe the interaction of two merging stars of equal mass whose combined mass exceeds the Chandrashekar limit? 05:25: ... gravity and the other forces, and a huge difference between the measured masses of the known particles and what we expect their masses to be from ... 06:15: But the supersymmetric counterparts do their jobs most neatly if they have masses-slash-energies in a particular range: between 100 and 1000 GeV. 04:09: ... generated collisions energetic enough to produce the very massive top quark, and so enabled the discovery of the final Fermion - or matter ... 16:17: That happens in the cores of massive stars when they die. 04:09: ... generated collisions energetic enough to produce the very massive top quark, and so enabled the discovery of the final Fermion - or matter ... 16:17: That happens in the cores of massive stars when they die.
	2020-08-17: How Stars Destroy Each Other 05:18: And its mass is high enough it sucks itself into a black hole. 06:42: The nearest such system is the famous Cynus X1 X-ray binary, where a black hole the mass of 15 Suns is busy gorging on a blue giant star. 08:10: In this case the companion didn’t start out as a brown dwarf - it became one after losing most of its mass to its ravenous partner. 09:38: The white dwarf in these systems builds up mass until releasing it as a nova. 09:47: The rest stays with the white dwarf, which slowly grows in mass. 10:54: ... that seemed to straddle the mass between black holes and neutron stars, and which will change the way we ... 11:14: ... its core becomes a neutron star - but if that core is above a certain mass it shrinks so that the escape velocity at its surface is greater than ... 12:12: ... dense matter of the early universe, and these would have different mass restrictions than stellar black ... 12:44: ... primordial black holes exist in some abundance at these masses, then the universe should be very faintly humming with a gravitational ... 13:22: The waves get generated when extreme masses spiral together at very small distances. 12:12: ... dense matter of the early universe, and these would have different mass restrictions than stellar black ... 12:44: ... primordial black holes exist in some abundance at these masses, then the universe should be very faintly humming with a gravitational ... 13:22: The waves get generated when extreme masses spiral together at very small distances. 05:02: Those are what you get when the most massive stars die. 07:58: ... a companion star - in this case a brown dwarf, which is a star not quite massive enough to generate its own energy by nuclear ... 11:14: ... give everyone some context: When a massive star dies, its core becomes a neutron star - but if that core is above a ... 12:21: ... for other LIGO mergers - which often involve black holes MORE massive than was thought normal for stellar remnants could ... 12:32: ... it’s also possible that primordial black holes could be less massive than black holes that come from stars, so might explain this weird ... 13:12: Some of you also asked why the less massive object can't just be a regular star. 05:02: Those are what you get when the most massive stars die. 07:58: ... a companion star - in this case a brown dwarf, which is a star not quite massive enough to generate its own energy by nuclear ... 11:14: ... give everyone some context: When a massive star dies, its core becomes a neutron star - but if that core is above a ... 12:21: ... for other LIGO mergers - which often involve black holes MORE massive than was thought normal for stellar remnants could ... 12:32: ... it’s also possible that primordial black holes could be less massive than black holes that come from stars, so might explain this weird ... 13:12: Some of you also asked why the less massive object can't just be a regular star. 11:14: ... give everyone some context: When a massive star dies, its core becomes a neutron star - but if that core is above a ... 05:02: Those are what you get when the most massive stars die.
	2020-08-10: Theory of Everything Controversies: Livestream 00:00: ... of gravity is that the interaction becomes stronger with larger masses so strictly speaking when we say that we can't test quantum gravity ...
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... know from uh e equals m c squared if nature has a particle with the mass m that's all the way up here and we as a species have only ever built ...
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 01:04: ... based on calculations using Einstein’s general theory of relativity, the masses of those bodies were ... 01:14: One was a hefty 23 times the mass of our Sun - making it definitely a black hole, and pretty similar to other LIGO mergers. 01:22: Its companion was puny by comparison - a mere 2.6 solar masses. 01:29: ... that mass, it’s pushing the limit for what was thought possible for a neutron star, ... 02:44: ... the shape of the detected waveform, the masses of the merging objects were figured figured out as 23.2 and 2.59 solar ... 04:33: And why are we all so excited to spot something with this mass at all? 05:58: Now in the case of normal matter, you can’t just add mass to make a black hole because as you do so the radius of the object increases. 06:07: That means the surface gets further away from the center, which means you don’t get the full impact of that extra mass. 06:22: One of its weird properties is that as you add mass the size does not necessarily increase, and at the highest masses the size actually gets smaller. 06:36: So more mass in a neutron star means higher surface gravity means higher escape velocity. 06:42: For any given mass, there’s a certain size that if you could crunch an object down below that size it would be a black hole. 07:00: As you increase a neutron star’s mass, its phantom event horizon grows while its actual surface shrinks. 07:49: ... in the neutron star determines how a neuron star’s size changes with mass - and that’s what determines the maximum possible ... 08:00: Those models have predicted maximum masses in the range 2 to 3 times the mass of the sun. 08:34: We’ve estimated a maximum neutron star mass of between 2.2 to 2.4 solar masses. 08:43: ... direct measurements of neutron star masses come from pulsars - cosmic lighthouses that result from a neutron star’s ... 08:53: Most pulsars are closer to the minimum neutron star mass of around 1.4 solar masses. 09:06: All of these numbers are quite a bit lower the 2.6 solar masses of this new guy. 09:33: So far we’ve never observed a black hole with masses lower than around 5 times that of the Sun. 09:47: ... may seem weird that there seems to be a gap in masses between the biggest neuron stars and the smallest black holes, but ... 10:24: That increases the black hole’s mass quite a bit. 10:28: Based on our calculations and simulations of how stars die, that minimum black hole mass of 5 Suns seems about right. 10:36: A black hole with 2.6 solar masses is difficult to explain. 11:53: It’s a brand new 2.6 solar mass black hole. 07:49: ... in the neutron star determines how a neuron star’s size changes with mass - and that’s what determines the maximum possible ... 11:53: It’s a brand new 2.6 solar mass black hole. 01:04: ... based on calculations using Einstein’s general theory of relativity, the masses of those bodies were ... 01:22: Its companion was puny by comparison - a mere 2.6 solar masses. 02:44: ... the shape of the detected waveform, the masses of the merging objects were figured figured out as 23.2 and 2.59 solar ... 06:22: One of its weird properties is that as you add mass the size does not necessarily increase, and at the highest masses the size actually gets smaller. 08:00: Those models have predicted maximum masses in the range 2 to 3 times the mass of the sun. 08:34: We’ve estimated a maximum neutron star mass of between 2.2 to 2.4 solar masses. 08:43: ... direct measurements of neutron star masses come from pulsars - cosmic lighthouses that result from a neutron star’s ... 08:53: Most pulsars are closer to the minimum neutron star mass of around 1.4 solar masses. 09:06: All of these numbers are quite a bit lower the 2.6 solar masses of this new guy. 09:33: So far we’ve never observed a black hole with masses lower than around 5 times that of the Sun. 09:47: ... may seem weird that there seems to be a gap in masses between the biggest neuron stars and the smallest black holes, but ... 10:36: A black hole with 2.6 solar masses is difficult to explain. 02:44: ... of the merging objects were figured figured out as 23.2 and 2.59 solar masses - and we’ll get back to why those are ... 09:33: So far we’ve never observed a black hole with masses lower than around 5 times that of the Sun. 04:44: A neutron star is what’s left after some massive stars explode as supernovae. 07:11: This basic picture is pretty well accepted, but we still aren’t sure just how massive a neutron star can be before becoming a black hole. 08:59: But, the most massive so far is around 2.1 Suns. 09:58: New black holes are formed when the most massive stars die and the core is too big to become a neutron star. 04:44: A neutron star is what’s left after some massive stars explode as supernovae. 07:11: This basic picture is pretty well accepted, but we still aren’t sure just how massive a neutron star can be before becoming a black hole. 08:59: But, the most massive so far is around 2.1 Suns. 09:58: New black holes are formed when the most massive stars die and the core is too big to become a neutron star. 04:44: A neutron star is what’s left after some massive stars explode as supernovae. 09:58: New black holes are formed when the most massive stars die and the core is too big to become a neutron star. 04:44: A neutron star is what’s left after some massive stars explode as supernovae.
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 05:19: ... counterpart, besides the charge and spin thing — it must have the same mass, the same quantum energy levels, and the same interactions with its ... 09:19: ... one of these states is determined by many different factors: the precise mass and charge of the particles, their orbital angular momentum, their ...
	2020-06-30: Dissolving an Event Horizon 02:22: According to the so-called no-hair theorem, black holes can have only three properties - mass, electric charge, and spin. 02:31: Mass is what makes a black hole a black hole, and so the simplest black holes have only this property. 02:37: These are Schwarzschild black holes, and with only mass that means they also only have inward-pulling gravity. 03:09: The same rotation that f orms the ring also drags the fabric of space into a vortex which counters the inward pull due to the singularity’s mass. 04:57: In both cases, the amount of angular momentum or charge you can fit into a black hole before it becomes extremal depends on the mass. 05:07: More mass means more inward gravity, and so the black hole can hold more spin and charge before going extremal. 05:29: Normal black holes leak their mass away by emitting Hawking radiation. 05:52: So that means a massive CHARGED black hole will slowly leak away its mass while retaining its charge. 06:06: This can’t happen with rotating black holes because they leak away their angular momentum as well as their mass. 09:41: ... have to be careful, because those particles increase the mass of the black hole as well as the charge - and if the mass increases too ... 09:51: ... electrons have very tiny masses for comparatively large charge - just factoring the electrons mass, it ... 10:12: As Einstein taught us, mass and energy are equivalent. 10:23: In fact the field itself will always generate enough mass to prevent the black hole from losing its event horizon. 02:22: According to the so-called no-hair theorem, black holes can have only three properties - mass, electric charge, and spin. 09:41: ... increase the mass of the black hole as well as the charge - and if the mass increases too much it won’t go ... 09:51: ... electrons have very tiny masses for comparatively large charge - just factoring the electrons mass, it ... 05:33: That radiation cian be any type of elementary particle - but in the case of the most massive black holes, it’s mostly just photons. 05:40: That’s because the more massive the black hole the lower the temperature of the radiation. 05:45: In very massive black holes the Hawking radiation has trouble mustering the energy for anything but weak photons. 05:52: So that means a massive CHARGED black hole will slowly leak away its mass while retaining its charge. 05:33: That radiation cian be any type of elementary particle - but in the case of the most massive black holes, it’s mostly just photons. 05:40: That’s because the more massive the black hole the lower the temperature of the radiation. 05:45: In very massive black holes the Hawking radiation has trouble mustering the energy for anything but weak photons. 05:52: So that means a massive CHARGED black hole will slowly leak away its mass while retaining its charge. 05:33: That radiation cian be any type of elementary particle - but in the case of the most massive black holes, it’s mostly just photons. 05:45: In very massive black holes the Hawking radiation has trouble mustering the energy for anything but weak photons. 05:33: That radiation cian be any type of elementary particle - but in the case of the most massive black holes, it’s mostly just photons. 05:45: In very massive black holes the Hawking radiation has trouble mustering the energy for anything but weak photons. 05:52: So that means a massive CHARGED black hole will slowly leak away its mass while retaining its charge.
	2020-06-22: Building Black Holes in a Lab 05:25: ... that real black holes would, contrary to prior thought, leak away their mass as a type of radiation. The popular description is that pairs of virtual ... 06:33: ... over the effect, essentially just saying that black holes must lose mass for the sake of energy ... 03:05: ... itself and you have a black hole. The surface around the central, massive point where the waterfall of space equals the speed of light is our ...
	2020-06-15: What Happens After the Universe Ends? 06:32: And in order to do that, the clock must have mass. 07:31: But the others do have mass, so presumably there’s still a way for the universe to tell that it’s gigantic. 07:38: Penrose speculates that mass itself may not be a fundamental property, and may eventually decay to leave massless electrons, etc. 07:50: But it’s not absurd to imagine their mass decaying. 07:53: ... masses of the elementary particles are not some fundamental property of those ... 08:01: I’ll come back to why we might expect the mass granted by the Higgs field to change over time. 08:24: Two ways to think about this: A particle's energy is a combination of its kinetic energy and rest mass energy. 08:31: Kinetic energies were so high at the big bang that rest mass energy was completely negligible - all particles behaved like light-speed particles. 08:39: And that’s precisely true for things like quarks and electrons, which gain their masses from interactions with the Higgs field. 08:46: But that only works below a certain temperature - in the extreme temperatures of the Big Bang, the Higgs field could not grant mass. 08:57: ... - if it decayed to a lower energy - could eliminate elementary particle masses in the late universe ... 07:50: But it’s not absurd to imagine their mass decaying. 08:24: Two ways to think about this: A particle's energy is a combination of its kinetic energy and rest mass energy. 08:31: Kinetic energies were so high at the big bang that rest mass energy was completely negligible - all particles behaved like light-speed particles. 08:01: I’ll come back to why we might expect the mass granted by the Higgs field to change over time. 07:53: ... masses of the elementary particles are not some fundamental property of those ... 08:39: And that’s precisely true for things like quarks and electrons, which gain their masses from interactions with the Higgs field. 08:57: ... - if it decayed to a lower energy - could eliminate elementary particle masses in the late universe ... 13:28: Penroses proposes that the collisions of super massive black holes in the previous universe may leave rings on the sky in the next. 07:27: The photons and gravitons are massless - you can’t build clocks with them. 07:38: Penrose speculates that mass itself may not be a fundamental property, and may eventually decay to leave massless electrons, etc. 08:19: Well yeah, but those particles were effectively massless also. 09:05: In the first tiny fraction of a second we can think of the universe as being full of effectively or actually massless particles. 11:10: Only radiation - light and other massless particles - can cross over this conformal boundary from one aeon into the next. 07:27: The photons and gravitons are massless - you can’t build clocks with them. 07:38: Penrose speculates that mass itself may not be a fundamental property, and may eventually decay to leave massless electrons, etc. 09:05: In the first tiny fraction of a second we can think of the universe as being full of effectively or actually massless particles. 11:10: Only radiation - light and other massless particles - can cross over this conformal boundary from one aeon into the next.
	2020-06-08: Can Viruses Travel Between Planets? 14:38: Some invisible mass is still needed, and so that eliminates a lot of the elegance of the idea. 15:01: ... A few of you had a really interesting insight - I said that when the masses of the Cavendish experiment are very close together, you need to factor ... 15:37: ... to measure a Casimir force that has a simple dependency on the mass of the two plates and their ... 15:01: ... A few of you had a really interesting insight - I said that when the masses of the Cavendish experiment are very close together, you need to factor ... 03:59: ... pushing their gene-transferring powers that far back means they may have massively accelerated the evolution that led to the development from RNA-based ... 04:57: Cellular life massively alters the atmosphere because it excretes gases - oxygen, methane, nitrous oxide as that light metabolizes. 03:59: ... pushing their gene-transferring powers that far back means they may have massively accelerated the evolution that led to the development from RNA-based ... 04:57: Cellular life massively alters the atmosphere because it excretes gases - oxygen, methane, nitrous oxide as that light metabolizes. 03:59: ... pushing their gene-transferring powers that far back means they may have massively accelerated the evolution that led to the development from RNA-based pseudo-life to ... 04:57: Cellular life massively alters the atmosphere because it excretes gases - oxygen, methane, nitrous oxide as that light metabolizes.
	2020-05-27: Does Gravity Require Extra Dimensions? 08:50: So, Cavendish placed large masses near each of the lead balls at the ends of the rods.. 08:55: ... gravitational attraction between these masses and the balls would then rotate the torsion pendulum ever so slightly, ... 09:24: ... allowed him to measure a force of gravity between the masses which was something like 10 million times smaller than the force the ... 10:15: ... of modern devices allow more precise positioning between the test masses, and the displacement of the masses is measured with far more ... 10:28: In some cases, rotating masses produce oscillations in the torsion pendulum. 10:40: ... advances have also allowed us to place the pendulum masses and the test masses extremely close together, as close as 50 micrometers ... 08:50: So, Cavendish placed large masses near each of the lead balls at the ends of the rods.. 08:55: ... gravitational attraction between these masses and the balls would then rotate the torsion pendulum ever so slightly, ... 09:24: ... allowed him to measure a force of gravity between the masses which was something like 10 million times smaller than the force the ... 10:15: ... of modern devices allow more precise positioning between the test masses, and the displacement of the masses is measured with far more ... 10:28: In some cases, rotating masses produce oscillations in the torsion pendulum. 10:40: ... advances have also allowed us to place the pendulum masses and the test masses extremely close together, as close as 50 micrometers ... 10:28: In some cases, rotating masses produce oscillations in the torsion pendulum. 01:53: ... force drops off with the square of the distance between two massive ... 02:03: If we have a massive object, we can depict the gravitational force (field) from this object as little arrows pointing towards the object. 01:53: ... force drops off with the square of the distance between two massive ... 02:03: If we have a massive object, we can depict the gravitational force (field) from this object as little arrows pointing towards the object. 01:53: ... force drops off with the square of the distance between two massive objects. ...
	2020-05-18: Mapping the Multiverse 01:01: ... black hole results when enough mass is concentrated in a small enough space that the gravitational field ... 01:16: ... that mass is NOT rotating and does not have any electric charge, the result is a ... 01:47: It describes the way spacetime warps and flows in the vicinity of a spinning mass. 07:34: For one thing, the ring singularity becomes entirely repulsive - as though it had negative mass. 12:42: ... this so-called mass inflation means the inner structure of the Kerr black hole is ... 13:13: ... Reissner-Nordström black holes the electromagnetic field within causes massive tension, or negative pressure that produces an antigravitational ... 14:25: Elliot Heath wonders if we are now in a similar position to the end of the 19th century now - in that we might be on the cusp of massive change. 14:44: And I'd say most HOPE for massive change, because that's probably whats needed to find a way forward. 13:13: ... Reissner-Nordström black holes the electromagnetic field within causes massive tension, or negative pressure that produces an antigravitational ... 14:25: Elliot Heath wonders if we are now in a similar position to the end of the 19th century now - in that we might be on the cusp of massive change. 14:44: And I'd say most HOPE for massive change, because that's probably whats needed to find a way forward. 14:25: Elliot Heath wonders if we are now in a similar position to the end of the 19th century now - in that we might be on the cusp of massive change. 14:44: And I'd say most HOPE for massive change, because that's probably whats needed to find a way forward. 13:13: ... Reissner-Nordström black holes the electromagnetic field within causes massive tension, or negative pressure that produces an antigravitational ...
	2020-05-04: How We Know The Universe is Ancient 11:07: ... part is figuring out how much of all that stuff there actually is. The mass of the universe - which is mostly in dark matter - can be found by ... 15:09: ... field, if you will. Same as with the rubber sheet analogy in which a massive body depresses the sheet. What "dimension" is the sheet depressing into? ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... my browser you guys are you guys are flicking through so fast favorite Mass Effect game there were multiple Mass Effect questions actually ...
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 08:42: ... matter is anything with negative energy density. Something with negative mass could produce the required negative gravity. But actually “exotic ... 09:17: ... are constraints that are placed on allowable distributions of mass and energy in Einstein’s equation in order for those equations to make ... 09:44: ... is probably always countered by the positive energy density of the mass of the plates themselves for any physically possible ...
	2020-04-14: Was the Milky Way a Quasar? 00:47: ... only is it home to an enormous black hole four million times the mass of the Sun, but it also swarms with smaller black holes, searing hot ... 08:16: Now A full quasar might devour many millions of times the mass of the Sun over one active period, which could last for several million years. 08:25: ... lot of that mass goes into the black hole, but 10% or more is converted into energy in ... 08:42: ... Fermi Bubbles, Sag A* would have needed to devour - a single 50 solar mass star that happened to wander too ... 00:47: ... but it also swarms with smaller black holes, searing hot clouds of gas, massive stars right on the edge of going supernova, and some of the most ... 03:18: ... of a diffuse cloud of gamma rays, they saw a massive pair of high-energy gamma ray bubbles with sharp edges extending more ... 03:42: How does something so massive and so powerful stay hidden for so long? 07:09: ... by an enormous number of supernova explosions because the most massive stars produced in the starburst die - rather explosively - very ... 07:25: ... the interstellar medium, potentially resulting in something like the massive bubble-shaped cavities we see ... 09:54: A mini AGN phase is triggered either by an influx of gas or by a random massive star getting too close to the black hole. 00:47: ... but it also swarms with smaller black holes, searing hot clouds of gas, massive stars right on the edge of going supernova, and some of the most ... 03:18: ... of a diffuse cloud of gamma rays, they saw a massive pair of high-energy gamma ray bubbles with sharp edges extending more ... 03:42: How does something so massive and so powerful stay hidden for so long? 07:09: ... by an enormous number of supernova explosions because the most massive stars produced in the starburst die - rather explosively - very ... 07:25: ... the interstellar medium, potentially resulting in something like the massive bubble-shaped cavities we see ... 09:54: A mini AGN phase is triggered either by an influx of gas or by a random massive star getting too close to the black hole. 07:25: ... the interstellar medium, potentially resulting in something like the massive bubble-shaped cavities we see ... 03:18: ... of a diffuse cloud of gamma rays, they saw a massive pair of high-energy gamma ray bubbles with sharp edges extending more than ... 09:54: A mini AGN phase is triggered either by an influx of gas or by a random massive star getting too close to the black hole. 00:47: ... but it also swarms with smaller black holes, searing hot clouds of gas, massive stars right on the edge of going supernova, and some of the most energetic ... 07:09: ... by an enormous number of supernova explosions because the most massive stars produced in the starburst die - rather explosively - very ...
	2020-03-31: What’s On The Other Side Of A Black Hole? 13:31: ... contains. for a maximally rotating black hole that's 40% of its total mass - all released as energy. To put that in context, think of any ...
	2020-03-24: How Black Holes Spin Space Time 00:21: ... describes the warping of space and time around a spherically symmetric mass. And if that mass is sufficiently compressed, the metric predicts an ... 01:35: According to the no-hair theorem, black holes can have three and only three properties: mass, electric charge, and spin. 01:44: ... black hole must have mass. Compacting a lot of mass into a tiny region is what makes them black ... 02:36: ... yielding the Kerr metric and describing the Kerr black hole, which has mass and rotation but no ... 03:18: It can be used to calculate the path of any body moving near or even within a Kerr black hole - or indeed any rotating mass. 04:26: ... a black hole in general relativity rotating or otherwise - without any mass. Warp spacetime so it looks like the exterior of a black hole, and that ... 05:14: ... black hole is known as frame-dragging. We see it around any rotating mass. In frame dragging, any “freefall” trajectory - the path taken by an ... 09:17: ... than it had coming in - up to 20% of the energy than was bound up in the mass of the half that was ... 12:36: ... reality, the maneuverability of a ship is influenced by hull shape, ship mass, power plant output, and many other factors. And World of Warships ... 01:44: ... black hole must have mass. Compacting a lot of mass into a tiny region is what makes them black holes in the ... 01:35: According to the no-hair theorem, black holes can have three and only three properties: mass, electric charge, and spin. 12:36: ... reality, the maneuverability of a ship is influenced by hull shape, ship mass, power plant output, and many other factors. And World of Warships captures the ... 04:26: ... a black hole in general relativity rotating or otherwise - without any mass. Warp spacetime so it looks like the exterior of a black hole, and that ... 09:06: ... Roger Penrose figured this out in the early 70s. It goes like this: a massive object is dropped into the ergosphere of a kerr black hole on a ... 11:31: ... happen to be along the paths of one of these jets, relativistic effects massively magnify its brightness. We see these as gamma ray bursts from over 13 ... 12:36: ... for supporting PBS. World o f Warships is a naval warfare-themed massively multiplayer online game, where players can battle others at random or ... 09:06: ... Roger Penrose figured this out in the early 70s. It goes like this: a massive object is dropped into the ergosphere of a kerr black hole on a ... 11:31: ... happen to be along the paths of one of these jets, relativistic effects massively magnify its brightness. We see these as gamma ray bursts from over 13 ... 12:36: ... for supporting PBS. World o f Warships is a naval warfare-themed massively multiplayer online game, where players can battle others at random or ... 11:31: ... happen to be along the paths of one of these jets, relativistic effects massively magnify its brightness. We see these as gamma ray bursts from over 13 BIllion ... 12:36: ... for supporting PBS. World o f Warships is a naval warfare-themed massively multiplayer online game, where players can battle others at random or play ...
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 13:54: ... beginning - before the Higgs mechanism gave elementary particles their mass. ... 14:51: ... axions produced in stars now would be a tiny fraction of the mass we see in dark matter - in fact they'd be a tiny fraction of the mass we ... 16:17: ... like an ancient roman or princhipia like a modern Italian or latin mass, and whether Newton himself would have said the latter - it seems ... 14:05: The idea is when that event occurred and axions became massive, they may have experienced a sort of friction that robbed them of their kinetic energy.
	2020-02-11: Are Axions Dark Matter? 06:54: ... charge, no quantum spin, be extreme ly light - a tiny fraction of the mass of the already tiny ... 06:32: ... solution to the strong CP problem its's that if any of the quarks are massless, CP symmetry is automatically conserved. However, as far as we can tell, ...
	2020-02-03: Are there Infinite Versions of You? 07:55: ... things like the mass or charge or other properties of individual particles, an infinite range ... 13:09: ... solutions work very well in some cases - for example if one of the masses is much heavier than the other then the Schwarzschild solution gives ... 13:49: ... the 3rd body has a low mass relative to the others then the original 2-body system is undisturbed, ... 13:59: ... willing to adjust the original 2-body system then a 3rd body of any mass can be added - either with 3 bodies in a permanent straight line or in ... 13:49: ... the 3rd body has a low mass relative to the others then the original 2-body system is undisturbed, and in ... 13:09: ... solutions work very well in some cases - for example if one of the masses is much heavier than the other then the Schwarzschild solution gives ... 06:31: In such a chaotic system, even tiny differences in the starting conditions will lead to massive divergences in that future history.
	2020-01-27: Hacking the Nature of Reality 08:57: ... in turn allowed him to explain the peculiar relationship between the mass and the spin of ... 15:56: ... supermassive black holes a few tens of millions to 10 billion times the mass of the sun - and the small end of that range is indeed a "little" ... 14:22: If you place any massive body in an accretion disk it will both tug on and be tugged by the surrounding gas.
	2020-01-20: Solving the Three Body Problem 04:29: ... useful approximation is when one of the three bodies has a very low mass compared to the other two. We can ignore the minuscule gravitational ... 05:01: ... fail to predict perfectly. Even the smallest planetary bodies have some mass, and the solar system as a whole has many massive constituents. The Sun, ... 05:25: ... a straight line or a segment of two-body path around the center of mass of the entire system, assuming everything else stays fixed. If you break ... 06:43: ... family of solutions for three bodies orbiting around a mutual center of mass, where all bodies remain in a straight line - essentially in permanent ... 07:56: ... Michel Henon and Roger Broucke found a family of solutions involving two masses bouncing back and forth in the center of a third body’s orbit. In the ... 08:46: ... system are the vertices of a triangle, whose center is the center of mass of the system. The evolution of the system can be expressed through the ... 04:29: ... useful approximation is when one of the three bodies has a very low mass compared to the other two. We can ignore the minuscule gravitational influence of ... 07:56: ... Michel Henon and Roger Broucke found a family of solutions involving two masses bouncing back and forth in the center of a third body’s orbit. In the ... 05:01: ... bodies have some mass, and the solar system as a whole has many massive constituents. The Sun, Jupiter and Saturn alone are automatically a ...
	2020-01-13: How To Capture Black Holes 02:50: ... contains a supermassive black hole of millions to billions of times the mass of the Sun. Recently we’ve also learned that the galactic center likely ... 04:50: ... does the presence of an accretion disk mean for the swarm of stellar mass black holes? The orbits of those black holes are mostly random, so the ... 05:37: ... the accretion disk. There they gorge on the gas of the disk and grow in mass much, much faster than they could in almost anywhere else in the galaxy. ... 07:17: ... mergers. And boosting the mergers also helps black holes to grow in mass more quickly. Multiple black holes can end up in the same migration trap ... 09:21: ... so powerful that it can carry away up to several percent of the original mass of the two black ... 12:17: ... Shouldn't a universe that's born inside a black hole be limited in mass by the amount of stuff that falls into that black hole? Well, the answer ... 04:50: ... does the presence of an accretion disk mean for the swarm of stellar mass black holes? The orbits of those black holes are mostly random, so the swarm ... 07:17: ... paper by Jillian Bellovary and co. predicts that behemoth “intermediate mass” black holes can form, with 1000s of times the mass of the ... 04:50: ... does the presence of an accretion disk mean for the swarm of stellar mass black holes? The orbits of those black holes are mostly random, so the swarm forms a ... 07:17: ... paper by Jillian Bellovary and co. predicts that behemoth “intermediate mass” black holes can form, with 1000s of times the mass of the ... 00:59: ... waves and astrophysics predicted black hole mergers. When two very massive stars are in binary orbit with each other, they may end their lives to ... 01:54: ... surprises. For one thing, many of the merging black holes were too massive to have been formed by the collapse of stellar cores. That is if our ... 02:50: ... Sun. They rained down on the galactic center over billions of years as massive stars formed and died in the surrounding galactic core. This has been a ... 04:08: ... there’s a way to massively accelerate the mergers of these black holes: all you need is a little ... 06:15: ... really cool, because the process is similar to how planets form. When a massive object is embedded in a rotating disk, it will exert a gravitational tug ... 07:17: ... This mechanism helps lone black holes find each other, so it should massively boost the number mergers. And boosting the mergers also helps black ... 08:27: ... sounds exciting and fun - and it may explain why so many surprisingly massive black hole mergers are observed. And if we spot more and more high-mass ... 00:59: ... waves and astrophysics predicted black hole mergers. When two very massive stars are in binary orbit with each other, they may end their lives to ... 01:54: ... surprises. For one thing, many of the merging black holes were too massive to have been formed by the collapse of stellar cores. That is if our ... 02:50: ... Sun. They rained down on the galactic center over billions of years as massive stars formed and died in the surrounding galactic core. This has been a ... 06:15: ... really cool, because the process is similar to how planets form. When a massive object is embedded in a rotating disk, it will exert a gravitational tug ... 08:27: ... sounds exciting and fun - and it may explain why so many surprisingly massive black hole mergers are observed. And if we spot more and more high-mass ... 06:15: ... really cool, because the process is similar to how planets form. When a massive object is embedded in a rotating disk, it will exert a gravitational tug on the ... 00:59: ... waves and astrophysics predicted black hole mergers. When two very massive stars are in binary orbit with each other, they may end their lives to leave a ... 02:50: ... Sun. They rained down on the galactic center over billions of years as massive stars formed and died in the surrounding galactic core. This has been a ... 04:08: ... there’s a way to massively accelerate the mergers of these black holes: all you need is a little ... 07:17: ... This mechanism helps lone black holes find each other, so it should massively boost the number mergers. And boosting the mergers also helps black ... 04:08: ... there’s a way to massively accelerate the mergers of these black holes: all you need is a little quasar. For ... 07:17: ... This mechanism helps lone black holes find each other, so it should massively boost the number mergers. And boosting the mergers also helps black holes to ...
	2020-01-06: How To Detect a Neutrino 05:15: ♪ ♪ In order to exist, they need to borrow a lot of energy to cover their rest mass. 05:05: ... 𝘢𝘳𝘱𝘦𝘨𝘨𝘪𝘰) ♪ Now, the thing about the weak force bosons is that they are massive, ♪ ♪ unlike the massless photon or gluon, which carry the electromagnetic ... 06:41: ... - that's the Proton Improvement Plan Two - ♪ ♪ which is going to *massively* increase the number of neutrinos ♪ ♪ that Fermilab will be able to send ... 05:05: ... 𝘢𝘳𝘱𝘦𝘨𝘨𝘪𝘰) ♪ Now, the thing about the weak force bosons is that they are massive, ♪ ♪ unlike the massless photon or gluon, which carry the electromagnetic ... 06:41: ... - that's the Proton Improvement Plan Two - ♪ ♪ which is going to *massively* increase the number of neutrinos ♪ ♪ that Fermilab will be able to send ... 05:05: ... about the weak force bosons is that they are massive, ♪ ♪ unlike the massless photon or gluon, which carry the electromagnetic and strong nuclear ...
	2019-12-17: Do Black Holes Create New Universes? 00:30: Why, for example, are the fundamental constants - like the mass of the electron or the strength of the forces - just right for the emergence of life? 03:26: ... Bryce deWitt, who postulated that when a black hole collapses, its mass doesn’t all end up stuck in the central, infinitely dense ... 09:20: Black holes only form when the neutron stars is above a certain mass limit. 09:41: And the lower the mass of the strange quark, the easier it is to convert lighter particles into strange quarks. 09:54: ... evolve to maximize the number of black holes, then the strange quark mass should be optimized to make the cutoff between neutron stars and black ... 10:08: Lee Smolin calculates that optimized cutoff at around 2 times the mass of the Sun. 10:14: So, if this universe is optimized for black hole production then there should be no neutron stars more massive than 2 solar masses. 10:24: Well, the most massive known neutron star is 2.17 solar masses, discovered just this year. 03:26: ... Bryce deWitt, who postulated that when a black hole collapses, its mass doesn’t all end up stuck in the central, infinitely dense ... 09:20: Black holes only form when the neutron stars is above a certain mass limit. 10:14: So, if this universe is optimized for black hole production then there should be no neutron stars more massive than 2 solar masses. 10:24: Well, the most massive known neutron star is 2.17 solar masses, discovered just this year. 03:54: There are various proposals for how such a bounce might happen - all of which are massively speculative, and perhaps we’ll cover another time. 05:49: In our modern universe, black holes are made when the most massive stars explode as supernovae. 05:59: So we should expect our universe to be optimized for producing as many of the most massive stars as possible. 09:09: ... massive stars die, they actually mostly produce neutron stars - planet sized ... 09:25: Now it may be that in the cores of the most massive neutron stars, some particles can convert into strange quarks. 09:48: That in turn means less massive neutron stars would be able to collapse into black holes. 10:14: So, if this universe is optimized for black hole production then there should be no neutron stars more massive than 2 solar masses. 10:24: Well, the most massive known neutron star is 2.17 solar masses, discovered just this year. 05:49: In our modern universe, black holes are made when the most massive stars explode as supernovae. 05:59: So we should expect our universe to be optimized for producing as many of the most massive stars as possible. 09:09: ... massive stars die, they actually mostly produce neutron stars - planet sized ... 09:25: Now it may be that in the cores of the most massive neutron stars, some particles can convert into strange quarks. 09:48: That in turn means less massive neutron stars would be able to collapse into black holes. 10:14: So, if this universe is optimized for black hole production then there should be no neutron stars more massive than 2 solar masses. 10:24: Well, the most massive known neutron star is 2.17 solar masses, discovered just this year. 09:25: Now it may be that in the cores of the most massive neutron stars, some particles can convert into strange quarks. 09:48: That in turn means less massive neutron stars would be able to collapse into black holes. 09:25: Now it may be that in the cores of the most massive neutron stars, some particles can convert into strange quarks. 09:48: That in turn means less massive neutron stars would be able to collapse into black holes. 05:49: In our modern universe, black holes are made when the most massive stars explode as supernovae. 05:59: So we should expect our universe to be optimized for producing as many of the most massive stars as possible. 09:09: ... massive stars die, they actually mostly produce neutron stars - planet sized balls of ... 05:49: In our modern universe, black holes are made when the most massive stars explode as supernovae. 03:54: There are various proposals for how such a bounce might happen - all of which are massively speculative, and perhaps we’ll cover another time.
	2019-12-09: The Doomsday Argument 03:31: ... the number of astronomers in a universe is proportional to the amount of mass that ends up forming galaxies in that ...
	2019-12-02: Is The Universe Finite? 04:04: The geometry of the universe is determined by two things: 1) the mass and energy it contains. 06:41: See, gravitational lensing is caused by mass - both dark matter and atoms. 07:14: ... details of inflation, the amount and behavior of all different types of mass and energy, ... 06:41: See, gravitational lensing is caused by mass - both dark matter and atoms. 15:52: ... that's probably some massively exponentially accelerating universe because the cosmological constant in ...
	2019-11-11: Does Life Need a Multiverse to Exist? 00:50: ... are things like the speed of light, the Planck constant, the masses of the elementary particles, and the constants defining the relative ... 08:01: Another set of free parameters are the masses of the elementary particles. 08:18: For example, if quarks or electrons had significantly different masses we’d once again be in a chemistry-free cosmos. 08:25: ... so it seems that the balance of the strengths of the forces and the masses of the elementary particles, is just right for things like stars and ... 00:50: ... are things like the speed of light, the Planck constant, the masses of the elementary particles, and the constants defining the relative ... 08:01: Another set of free parameters are the masses of the elementary particles. 08:18: For example, if quarks or electrons had significantly different masses we’d once again be in a chemistry-free cosmos. 08:25: ... so it seems that the balance of the strengths of the forces and the masses of the elementary particles, is just right for things like stars and ... 05:05: The vast majority of carbon in the universe is produced in the cores of massive stars. 05:36: Other slight changes in nuclear fine tuning would also massively reduce the amount of oxygen that stars produce. 05:05: The vast majority of carbon in the universe is produced in the cores of massive stars. 05:36: Other slight changes in nuclear fine tuning would also massively reduce the amount of oxygen that stars produce.
	2019-11-04: Why We Might Be Alone in the Universe 09:53: If we’d had a significantly higher rate of mass-extinction-level impacts, perhaps evolution would not have progressed so far. 03:05: ... Fermi Paradox notes the apparent contradiction between the massive abundance of potential opportunities for technical life to have emerged ... 10:55: ... an energy power house that allowed the new chimerical cell to massively increase its complexity, ultimately leading to the first multicellular ... 03:05: ... Fermi Paradox notes the apparent contradiction between the massive abundance of potential opportunities for technical life to have emerged ... 10:55: ... an energy power house that allowed the new chimerical cell to massively increase its complexity, ultimately leading to the first multicellular ...
	2019-10-21: Is Time Travel Impossible? 02:15: In order for any object with regular mass to even reach light speed it would need infinite energy – which can never be obtained. 02:23: ... notice I said “regular mass.” We can hack the equations of special relativity by allowing mass to take ... 02:35: An object with imaginary mass is now restricted to only traveling FASTER than light, never slower. 02:47: We call a particle with imaginary mass a tachyon. 02:57: Does imaginary mass exist? 03:16: ... a result of curvature in the fabric of spacetime due to the presence of mass and ... 05:17: We need to counter gravity, and to do that we need another probably-non-existent form of mass – negative mass – also referred to as exotic matter. 05:27: As far as we know, mass can only take on positive, real values, so a requirement of negative mass seems a non-starter. 06:19: But is negative mass-energy as much of a non-starter as imaginary mass? 06:58: And as it turns out, there may be other ways to build time machines without either negative or imaginary masses. 02:57: Does imaginary mass exist? 06:19: But is negative mass-energy as much of a non-starter as imaginary mass? 06:58: And as it turns out, there may be other ways to build time machines without either negative or imaginary masses.
	2019-10-15: Loop Quantum Gravity Explained 02:31: They describe how the presence of mass and energy warp the fabric of spacetime. 16:29: ... says that the amount stretching of spacetime is proportional to the mass and and energy contained by that ...
	2019-10-07: Black Hole Harmonics 06:10: ... exactly what parameters went into the signal – in particular black hole mass and spin, so you know if you got the right answer when you try to ... 07:12: Similarly, the overtone structure of a black hole ringdown can identify the fundamental properties of that black hole – namely its mass and spin. 07:22: ... researchers found that they could pinpoint the mass and spin of the simulated black holes with much greater precision than ... 08:09: ... LIGO reported: GW150914 – a pair of black holes, each 30 or so times the mass of the sun, spiraling into each other one and a half billion light years ... 08:43: By analyzing the harmonics, the team calculates the mass of the final black hole as 68.5 solar masses. 09:13: ... the mass and spin derived from the ringdown are consistent with the estimate that ... 09:44: General relativity predicts that black holes should be completely defined by three properties – their mass, spin, and electric charge. 10:08: ... black holes are also expected to have no electric charge, so mass and spin should define everything – including the nature of the ... 10:34: The oscillations are consistent with a black hole purely defined by its mass and spin. 09:44: General relativity predicts that black holes should be completely defined by three properties – their mass, spin, and electric charge. 08:43: By analyzing the harmonics, the team calculates the mass of the final black hole as 68.5 solar masses. 01:00: But real black holes are created in the violent deaths of massive stars, and there’s nothing clean about that. 11:21: LIGO and VIRGO have been in their 3rd observing run since April 1st after massive upgrades to sensitivity, and this run will last for one year. 01:00: But real black holes are created in the violent deaths of massive stars, and there’s nothing clean about that. 11:21: LIGO and VIRGO have been in their 3rd observing run since April 1st after massive upgrades to sensitivity, and this run will last for one year. 01:00: But real black holes are created in the violent deaths of massive stars, and there’s nothing clean about that. 11:21: LIGO and VIRGO have been in their 3rd observing run since April 1st after massive upgrades to sensitivity, and this run will last for one year.
	2019-09-30: How Many Universes Are There? 16:55: ... we end up with this somewhat complicated relationship between mass and distance from the Sun that determines whether you get called a ... 16:01: Here the IAU definition again: "A planet is a sun-orbiting body massive enough to be round and to have cleared it's orbit of debris". 16:30: ... on where in the solar system it forms - the further out, the more massive a body needs to be to clear its ... 16:01: Here the IAU definition again: "A planet is a sun-orbiting body massive enough to be round and to have cleared it's orbit of debris". 16:30: ... on where in the solar system it forms - the further out, the more massive a body needs to be to clear its ...
	2019-09-23: Is Pluto a Planet? 06:07: It also seemed too faint to possibly have the mass required to explain Uranus’s orbital discrepancies. 08:22: There must be hundreds more objects in the mass range of Pluto - and perhaps a couple of thousand. 09:09: Two - Have sufficient mass to assume hydrostatic equilibrium, meaning be roughly spherical. 14:58: Dwarf planet David is a frigid, lifeless ball of ice and rock half the mass of Pluto and orbiting at the outer rim of the Kuiper belt. 16:19: After all, it's closer in mass to the Earth and has an atmosphere - albeit a searing hot, horribly acidic one. 08:22: There must be hundreds more objects in the mass range of Pluto - and perhaps a couple of thousand. 06:07: It also seemed too faint to possibly have the mass required to explain Uranus’s orbital discrepancies. 06:54: ... giant orbs of gas aren’t massive enough to ignite nuclear fusion in their cores like a true star, but ... 07:04: And yet some brown dwarfs orbit other, more massive stars just like planets do. 08:08: It’s 28% more massive than Pluto, which spurred NASA to initially hail it as the tenth planet. 09:38: ... planet - an object which has its own orbit and is spherical-ish, but not massive enough to clear its ... 16:52: But presumedly, we'd need to massively alter and even reduce that atmosphere, if we want to terraform it, which would probably kill the field. 06:54: ... giant orbs of gas aren’t massive enough to ignite nuclear fusion in their cores like a true star, but ... 07:04: And yet some brown dwarfs orbit other, more massive stars just like planets do. 08:08: It’s 28% more massive than Pluto, which spurred NASA to initially hail it as the tenth planet. 09:38: ... planet - an object which has its own orbit and is spherical-ish, but not massive enough to clear its ... 07:04: And yet some brown dwarfs orbit other, more massive stars just like planets do. 16:52: But presumedly, we'd need to massively alter and even reduce that atmosphere, if we want to terraform it, which would probably kill the field.
	2019-09-16: Could We Terraform Mars? 03:33: At 11% the mass of Earth, it has a weaker gravitational field that grips less tightly to an atmosphere. 07:25: High density limestone is 2500 kg/m^3 and yields 44% of its mass in CO2 when heated or exposed to acid. 11:42: ... of the pre-solar nebula then can guess that around 5% of a comet’s mass is ...
	2019-08-26: How To Become an Astrophysicist + Challenge Question! 00:00: ... person in the room Then I'm probably in the wrong room grad school had massive ups and downs and I thought of quitting plenty of times It was amazing I ... 08:00: ... Just get it done Because once you have that PhD your options open up massively both in the field and out of it Okay, this gets me to the big question ... 00:00: ... person in the room Then I'm probably in the wrong room grad school had massive ups and downs and I thought of quitting plenty of times It was amazing I ... 08:00: ... Just get it done Because once you have that PhD your options open up massively both in the field and out of it Okay, this gets me to the big question ...
	2019-08-19: What Happened Before the Big Bang? 02:37: That's the Higgs field which gives elementary particles their mass.
	2019-07-18: Did Time Start at the Big Bang? 00:25: ... to Einstein's equations, it seems inevitable that all space and mass and energy should once have been compacted into an infinitesimally small ...
	2019-07-15: The Quantum Internet 11:50: It's really, really hard to even make a critical mass of fissile material explode like an atom bomb - it's a very precise engineering feat. 02:33: ... the ability for a qubit to hold many simultaneous states can lead to massive speed-ups in certain types of ... 05:32: But quantum information DOES allow us to massively extend the range over which we can send an intact qubit. 02:33: ... the ability for a qubit to hold many simultaneous states can lead to massive speed-ups in certain types of ... 05:32: But quantum information DOES allow us to massively extend the range over which we can send an intact qubit.
	2019-07-01: Thorium and the Future of Nuclear Energy 00:17: The question is "should it?" Energy isn't scarce. It's everywhere. Seriously, literally all mass is energy The trick is getting at it. 00:33: ... energy The Sun is powered that way Releasing a mere 0.4 percent of the mass of hydrogen nuclei as it fuses them into helium But that's enough to ... 02:49: ... have enough of these heavy nuclei, if you exceed what we call critical mass then neutrons produced in every fission trigger at least one more ... 16:59: ... Frame dragging is the dragging of the fabric of space around a rotating massive object in the case of a black hole it's most obvious effect is that it ...
	2019-06-20: The Quasar from The Beginning of Time 06:24: ... of matter moving near the black hole. That allows us to estimate the mass of the black hole: 800 million ...
	2019-06-17: How Black Holes Kill Galaxies 00:08: ... the entire Universe When we first realized that Black Holes could have masses of Millions or even Billions of times that of the Sun It came as a bit ... 01:35: ... itself depends on the total mass of the Galaxy including Dark Matter so why shouldn't a Galaxy and its ... 02:54: ... galaxies grew so did their Black Holes they would've started as a ready mass of seed Black Holes formed by the very first generation of stars they ... 04:05: ... grew faster than their surrounding galaxies The 'Galaxy Black Hole Mass Relationships' seem to evolve through the history of the Universe many ... 06:33: ... by the energy that's long formed it gets so hot that around 10% the mass of the infalling gas is converted to energy in the form of light and yet ... 07:21: ... more stuff it can pull in to feed itself in the Black Hole but the more mass of the Black hole, the better it is at shutting down the star formation ... 04:05: ... grew faster than their surrounding galaxies The 'Galaxy Black Hole Mass Relationships' seem to evolve through the history of the Universe many Supermassive ... 00:08: ... the entire Universe When we first realized that Black Holes could have masses of Millions or even Billions of times that of the Sun It came as a bit ... 04:05: ... shining out from less than a Billion years after the Big bang with masses of 10 Billion suns Easily as large as the largest in the modern Universe ... 05:24: ... star formation and haven't had any for long time The short-lived hot massive stars that give Spiral galaxies, like the Milky way, their blue-white ... 07:21: ... in the end you have this balancing act a feedback process the more massive the galaxy, the more stuff it can pull in to feed itself in the Black ... 05:24: ... star formation and haven't had any for long time The short-lived hot massive stars that give Spiral galaxies, like the Milky way, their blue-white ... 07:21: ... in the end you have this balancing act a feedback process the more massive the galaxy, the more stuff it can pull in to feed itself in the Black ... 05:24: ... star formation and haven't had any for long time The short-lived hot massive stars that give Spiral galaxies, like the Milky way, their blue-white sheen ...
	2019-06-06: The Alchemy of Neutron Star Collisions 00:34: ... are likely made by the slow Neutron capture or s-process inside low mass star and actually it turns out that even the heavy our protest isotopes ... 02:47: ... star mergers are likely the dominant source of most elements with atomic masses 44 and up that includes most of the Lead, Silver, Gold, rare earth ... 00:34: ... are likely made by the slow Neutron capture or s-process inside low mass star and actually it turns out that even the heavy our protest isotopes are ... 02:47: ... star mergers are likely the dominant source of most elements with atomic masses 44 and up that includes most of the Lead, Silver, Gold, rare earth ... 00:34: ... were produced in onion shells by nuclear fusion in the cores of very massive stars during the last phases of their lives and that elements heavier ... 02:47: ... let's take a look like I said neutron stars are the dead cause of massive stars they are composed almost entirely of neutrons a density similar to ... 00:34: ... were produced in onion shells by nuclear fusion in the cores of very massive stars during the last phases of their lives and that elements heavier ... 02:47: ... let's take a look like I said neutron stars are the dead cause of massive stars they are composed almost entirely of neutrons a density similar to ... 00:34: ... were produced in onion shells by nuclear fusion in the cores of very massive stars during the last phases of their lives and that elements heavier than ... 02:47: ... let's take a look like I said neutron stars are the dead cause of massive stars they are composed almost entirely of neutrons a density similar to the ...
	2019-05-16: The Cosmic Dark Ages 07:19: ... supermassive black holes with millions, even billions of times the Sun’s mass – inescapable spheres the size of solar systems. And in the final stage ... 02:52: ... to collapse under their own gravity. These stars were exceptionally massive because they were unpolluted by the heavier elements of the periodic ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 15:27: Occasional dark matter particles would be snared by black holes - and they would add to its mass just like regular matter.
	2019-05-01: The Real Science of the EHT Black Hole 01:00: It has an estimated mass of several billion times that of the Sun, which gives it an event horizon larger than the solar system. 06:04: For a non-rotating black hole the size of the event horizon is called the Schwarzschild radius, and it’s proportional to the mass of the black hole. 06:53: Measuring the radius of the photon sphere potentially gives you both black hole mass and spin. 09:19: ... team simulated a wide range of parameters like black hole mass and spin rate, while they were able to nail down the rotational axis ... 09:37: ... found that monster has a mass over 6 billion solar masses, with an event horizon that's about 1/5 the ... 01:44: Interferometry is a way of combining the light taken by two or more telescopes separated by some distance to massively improve their resolution. 08:27: ... asymmetry is probably due to relativistic beaming – brightness massively amplified when the material is moving in the same direction as the ... 01:44: Interferometry is a way of combining the light taken by two or more telescopes separated by some distance to massively improve their resolution. 08:27: ... asymmetry is probably due to relativistic beaming – brightness massively amplified when the material is moving in the same direction as the ... 01:44: Interferometry is a way of combining the light taken by two or more telescopes separated by some distance to massively improve their resolution.
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... that the rotation rates of spiral galaxies were too fast given the mass of their visible stars alone they should throw themselves to pieces ...
	2019-04-03: The Edge of an Infinite Universe 06:56: Any sub-lightspeed paths, which means anything with mass, will be swept along with the contours of space. 07:44: ... flat” – it may have some local curvature due to gravity of massive objects inside, but at its boundaries the simple rules of non-curved, ... 07:16: Only lightspeed paths – or in the language of quantum field theory “massless fields” can access these diagonal boundaries.
	2019-03-28: Could the Universe End by Tearing Apart Every Atom? 03:05: ... this is Einstein's gravity not Newton's, gravity is influenced by mass and energy density but also by pressure. Both mass energy density and ... 04:32: ... can express our lambda as a sort of equivalent mass and pressure in fact, let's make it an emo party and get rid of regular ... 12:11: ... the same energy conditions of general relativity that prohibit negative mass and time ... 15:06: The amount of mass and energy it contains just doesn't provide enough gravity. 03:05: ... is influenced by mass and energy density but also by pressure. Both mass energy density and any positive pressure act to decelerate the universe to ... 04:32: ... and pressure in fact, let's make it an emo party and get rid of regular massive pressure, after all, in the future dark energy will completely dominate ... 15:23: ... Pick notes that dark energy backs up their hypothesis that massive dinosaur fossils were actually originally chicken sized. The tiny bird ... 04:32: ... and pressure in fact, let's make it an emo party and get rid of regular massive pressure, after all, in the future dark energy will completely dominate ... 15:23: ... Pick notes that dark energy backs up their hypothesis that massive dinosaur fossils were actually originally chicken sized. The tiny bird ... 04:32: ... and pressure in fact, let's make it an emo party and get rid of regular massive pressure, after all, in the future dark energy will completely dominate the ...
	2019-03-20: Is Dark Energy Getting Stronger? 07:07: They can have a huge range of energy output, depending on the mass of the black hole and how much fuel it’s getting.
	2019-03-13: Will You Travel to Space? 07:28: ... rockets need to carry an oxidant to burn that fuel and a reaction mass – that's what you blast out to propel the rocket ... 07:45: Planes, on the other hand, can use air as both oxidant and reaction mass.
	2019-03-06: The Impossibility of Perpetual Motion Machines 02:12: ... overbalance wheel pushes masses outwards on one side, but that same at the same time increases the ... 09:54: ... up with a perpetual motion machine based on the funky notion of negative mass. ... 10:06: According to some interpretations, negative mass should be attracted to positive mass, but positive mass should be repelled by negative mass. 10:15: The result is that a positive and negative mass should accelerate indefinitely, potentially powering an infinite energy device. 10:45: Alex Taylor has an especially cool dynamo device in which the masses are contained in a magnetic field. 10:58: We have a rare non-dynamo device from Adrien Romeo, who uses cogs with negative and positive mass teeth. 02:12: ... overbalance wheel pushes masses outwards on one side, but that same at the same time increases the ... 10:45: Alex Taylor has an especially cool dynamo device in which the masses are contained in a magnetic field. 02:12: ... overbalance wheel pushes masses outwards on one side, but that same at the same time increases the separation ...
	2019-02-20: Secrets of the Cosmic Microwave Background 07:42: ... to use an analogy We can think of these oscillations as being like heavy masses attached to a spring Release the mass then it falls and then bounces up ... 12:34: ... modern Universe and we get the baryons constitute only about 5% of the mass and energy that's all of the atoms in all of the stars in all of the ... 07:42: ... to use an analogy We can think of these oscillations as being like heavy masses attached to a spring Release the mass then it falls and then bounces up ... 02:05: ... together As the baryons condensed into over-dense regions this led to a massive buildup of pressure Collapsing baryons rebounded producing an expanding ...
	2019-02-07: Sound Waves from the Beginning of Time 13:19: Today, it's the 'Crisis in cosmology' and 'Negative mass perpetual motion' episodes. 15:16: Ergo, time will prove negative mass' existence. 16:03: flux_capacitor notes an alternate model for how negative mass might behave. 16:08: In so-called bimetric gravity, you can have positive and negative masses, but each is described by its own set of Einstein field equations. 16:18: That's kind of like having parallel spacetimes, one with positive and one with negative masses, which can still interact gravitationally. 16:26: ... these models, like masses attract and opposite masses repel, but you don't get the crazy runaway ... 15:16: Ergo, time will prove negative mass' existence. 13:19: Today, it's the 'Crisis in cosmology' and 'Negative mass perpetual motion' episodes. 16:08: In so-called bimetric gravity, you can have positive and negative masses, but each is described by its own set of Einstein field equations. 16:18: That's kind of like having parallel spacetimes, one with positive and one with negative masses, which can still interact gravitationally. 16:26: ... these models, like masses attract and opposite masses repel, but you don't get the crazy runaway ...
	2019-01-30: Perpetual Motion From Negative Mass? 00:31: Matter with negative mass - has long been the pipedream of science fiction writers, futurists, and certain rather. 00:59: And we also recently covered a very new use for negative mass: as “dark fluid”, a proposed explanation for both dark matter and dark energy. 01:10: That episode really got me thinking about the subtleties of negative mass and how it should really behave gravitationally. 01:17: Turns out it’s complicated, and to answer it we really have to question the very definition of mass. 01:24: Let’s start with mass in Newton’s physics. 01:42: This type of acceleration-resisting mass is called inertial mass. 01:48: Mass is also the property that both causes and responds to gravity. 02:04: We refer to the mass that exerts or responds to a gravitational force gravitational mass. 02:12: ... we should split gravitational mass into active gravitational mass – that’s the mass that causes a ... 02:30: In fact both gravitational masses should be the same quantity as inertial mass. 02:46: ... an object in a gravitational field, inertial and passive gravitational mass cancel each other out - as long as they are they same ... 02:57: ... demonstrated the equivalence of gravitational and inertial mass when he showed that objects with very different masses fall at the same ... 03:19: OK, so how do negative masses work in Newtonian mechanics? 03:24: We know that the gravitational force between positive mass objects is attractive. 03:28: In fact, in Newtonian gravity, any like masses – both positive or both negative - should produce a mutually attractive force. 03:37: On the other hand opposite mass signs should repel. 04:00: ... field even means, but the gravitational field is spin 2 – even - so like masses should attract and opposite should ... 04:25: Except now we come back to the tricky relationship between inertial mass and gravitational mass. 04:31: In particular, what if passive gravitational and inertial mass is the same thing? 04:37: Newton’s second law seems to say that negative inertial masses respond oppositely to the applied force. 04:45: A repulsive force on a negative mass becomes an attractive force and vice versa. 04:51: ... in the dark fluid episode, but to recap: this suggests that two negative masses produce an attractive force which actually drives them ... 05:02: Even weirder, a positive mass should attract a negative mass while at the same time being repelled by it. 05:08: A negative mass apple would still fall to the Earth, and you wouldn’t notice Earth’s infinitesimal repulsion from the apple. 05:17: But put equal positive and negative masses next to each other and they should accelerate uniformly forever. 05:58: General relativity was, in part, inspired by the equivalence of gravitational and inertial mass. 06:17: ... equivalence principle only works if all masses experience the same acceleration in a given gravitational field, so ... 06:36: ... presence of active gravitational mass, and of energy, momentum, pressure, and more, change the geometry of ... 06:56: At first glance this tells us that any object, no matter its mass, will follow the geodesic determined by its starting position and velocity. 07:05: In fact, in pure general relativity, inertial and passive gravitational masses don’t even appear in the equations. 07:13: That should mean that a negative mass behaves the same in a gravitational field as a positive mass. 07:26: Positive mass causes spacetime to curve inwards – what we call positive curvature. 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 07:40: But those trajectories only depend on the active gravitational mass of the central object, and on the velocity and starting position of the apple. 07:47: The apple’s mass doesn’t come into it. 07:50: This suggests that a positive gravitational field attracts everything, including negative masses. 08:01: Negative mass causes negative curvature, which in our sheet analogy looks like pulling the sheet up. 08:13: That suggests that everything, regardless of mass, should be repelled from a negative mass. 08:21: It suggests that positive masses attract everything and negative masses repel everything, including each other. 08:29: A positive mass attracts and is repelled by a negative mass. 08:51: So a positive and a negative mass apple placed side by side should chase each other across the cosmos, accelerating forever. 09:06: ... positive mass apple gains positive momentum and energy as it speeds up, while the ... 09:46: ... fact the mere existence of negative mass breaks certain energy conditions, but the prospect of a bottomless well ... 10:03: In particular, with the idea of negative and positive masses accelerating each other to infinite energies? 10:26: Much less clear is the way a negative mass responds to an applied force. 10:32: We assumed that passive gravitational mass and inertial mass are the same thing – and that’s required by the equivalence principle. 10:39: We then happily plugged our negative inertial mass into Newton’s 2nd law to get acceleration. 11:22: Either way, the structure of geodesics have inbuilt the assumption of the equivalence of gravitational and inertial mass. 11:42: The real nonsense seems to be the idea of negative inertial mass. 11:48: By comparison, negative gravitational mass is kind of ok. 11:52: ... inertial mass implies flipping the sign of the acceleration when any force is applied ... 12:28: ... if we conclude that negative inertial mass can’t exist and we want to save the equivalence principle and the rest ... 12:55: Some say negative mass can’t exist, some say it can. 12:59: ... say that, if they do, then positive mass always attracts while negative mass always repels, while others say that ... 13:18: ... it is: assuming that positive mass both attracts and is repelled by negative mass, come up with a way to ... 13:59: Make the subject line negative mass challenge question. 00:31: Matter with negative mass - has long been the pipedream of science fiction writers, futurists, and certain rather. 05:08: A negative mass apple would still fall to the Earth, and you wouldn’t notice Earth’s infinitesimal repulsion from the apple. 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 08:51: So a positive and a negative mass apple placed side by side should chase each other across the cosmos, accelerating forever. 09:06: ... positive mass apple gains positive momentum and energy as it speeds up, while the negative ... 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 09:06: ... positive mass apple gains positive momentum and energy as it speeds up, while the negative mass ... 08:29: A positive mass attracts and is repelled by a negative mass. 07:13: That should mean that a negative mass behaves the same in a gravitational field as a positive mass. 09:46: ... fact the mere existence of negative mass breaks certain energy conditions, but the prospect of a bottomless well of ... 02:46: ... an object in a gravitational field, inertial and passive gravitational mass cancel each other out - as long as they are they same ... 13:59: Make the subject line negative mass challenge question. 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 07:47: The apple’s mass doesn’t come into it. 11:52: ... inertial mass implies flipping the sign of the acceleration when any force is applied to ... 03:24: We know that the gravitational force between positive mass objects is attractive. 13:18: ... a way to use a pair of infinitely accelerating positive and negative mass objects to build a perpetual motion ... 10:26: Much less clear is the way a negative mass responds to an applied force. 03:37: On the other hand opposite mass signs should repel. 12:59: ... attracts while negative mass always repels, while others say that like mass signs always attract and opposite mass signs always ... 02:30: In fact both gravitational masses should be the same quantity as inertial mass. 02:57: ... and inertial mass when he showed that objects with very different masses fall at the same rate, and that was before Newton came even ... 03:19: OK, so how do negative masses work in Newtonian mechanics? 03:28: In fact, in Newtonian gravity, any like masses – both positive or both negative - should produce a mutually attractive force. 04:00: ... field even means, but the gravitational field is spin 2 – even - so like masses should attract and opposite should ... 04:37: Newton’s second law seems to say that negative inertial masses respond oppositely to the applied force. 04:51: ... in the dark fluid episode, but to recap: this suggests that two negative masses produce an attractive force which actually drives them ... 05:17: But put equal positive and negative masses next to each other and they should accelerate uniformly forever. 06:17: ... equivalence principle only works if all masses experience the same acceleration in a given gravitational field, so ... 07:05: In fact, in pure general relativity, inertial and passive gravitational masses don’t even appear in the equations. 07:50: This suggests that a positive gravitational field attracts everything, including negative masses. 08:21: It suggests that positive masses attract everything and negative masses repel everything, including each other. 10:03: In particular, with the idea of negative and positive masses accelerating each other to infinite energies? 08:21: It suggests that positive masses attract everything and negative masses repel everything, including each other. 07:05: In fact, in pure general relativity, inertial and passive gravitational masses don’t even appear in the equations. 06:17: ... equivalence principle only works if all masses experience the same acceleration in a given gravitational field, so passive ... 02:57: ... and inertial mass when he showed that objects with very different masses fall at the same rate, and that was before Newton came even ... 04:51: ... in the dark fluid episode, but to recap: this suggests that two negative masses produce an attractive force which actually drives them ... 08:21: It suggests that positive masses attract everything and negative masses repel everything, including each other. 04:37: Newton’s second law seems to say that negative inertial masses respond oppositely to the applied force. 03:19: OK, so how do negative masses work in Newtonian mechanics? 01:56: The more massive an object, the more strongly its gravity pulls on surrounding objects and the more strongly it gets pulled by gravity. 02:35: ... second law with the law of gravitation and you see that although massive objects get pulled more strongly by gravity, they also accelerate more ... 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 01:56: The more massive an object, the more strongly its gravity pulls on surrounding objects and the more strongly it gets pulled by gravity. 02:35: ... second law with the law of gravitation and you see that although massive objects get pulled more strongly by gravity, they also accelerate more ... 07:31: In the analogy a positive mass depresses the sheet so that the trajectory of an positive mass apple bends towards the massive object. 02:35: ... second law with the law of gravitation and you see that although massive objects get pulled more strongly by gravity, they also accelerate more ...
	2019-01-24: The Crisis in Cosmology 13:26: ...about negative mass dark fluid... 14:06: ...will give the exact opposite results if dark matter is due to this negative mass fluid... 14:11: ...than if it's actual, positive mass matter. 14:30: We can use that warping to measure masses. 14:32: And yeah, those measures tell us that dark matter has positive mass I'd need to do the simulations, but I have a feeling... 14:48: Marik Zilberman's distaste for negative masses... 16:09: TinyFox Tom asks whether mass would be inverted under CPT symmetry. 16:31: And a negative mass particle, moving backwards in time,... 16:34: ...is mathematically the same as a positive mass particle moving forward in time That notion makes sense in the math,... 13:26: ...about negative mass dark fluid... 14:06: ...will give the exact opposite results if dark matter is due to this negative mass fluid... 14:11: ...than if it's actual, positive mass matter. 16:31: And a negative mass particle, moving backwards in time,... 16:34: ...is mathematically the same as a positive mass particle moving forward in time That notion makes sense in the math,... 16:31: And a negative mass particle, moving backwards in time,... 16:34: ...is mathematically the same as a positive mass particle moving forward in time That notion makes sense in the math,... 14:30: We can use that warping to measure masses. 14:48: Marik Zilberman's distaste for negative masses...
	2019-01-09: Are Dark Matter And Dark Energy The Same? 00:32: And it’s pretty wild: negative mass particles continuously popping into existence between the galaxies. 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 03:58: He tried to do this in very different way: with negative mass. 04:02: In physics, we usually assume that mass is always positive. 04:06: Forgetting that pressure stuff for a moment, positive masses and energies always have a positive gravitational effect. 04:15: So what about negative masses? 04:18: The answer is complicated - it’s not always obvious how weird stuff like negative masses translates from general relativity to Newton’s laws. 04:31: In Newtonian gravity, you multiply the two masses together along with some other stuff to get the strength of their mutual gravitational attraction. 04:40: Two positive masses always give an attractive force by definition. 04:45: Two negative masses should cancel each other’s signs so also give you an attractive force. 04:51: But with one negative and one positive mass, the final force of gravity has the opposite sign - that makes it repulsive. 05:03: Mass determines the strength and direction of the gravitational field – that’s gravitational mass. 05:14: In this equation, mass is inertial mass. 05:18: It should be the same as gravitational mass for the equivalence principle to hold. 05:23: For a positive inertial mass, direction of acceleration is the same as direction as the applied force. 05:29: For a negative mass, this equation suggests that acceleration is in the opposite direction to the applied force. 05:36: Push a negative mass away from you it’ll move towards you, pull it and it’ll move away. 05:45: So Farnes argues that the “attractive” gravitational force between two negative masses should actually drive them apart. 05:56: At the same time, the repulsive force between a negative and positive mass should repel the positive and attract the negative mass. 06:15: The author uses these ideas about the interactions of negative and positive mass particles to create an N-body simulation. 06:22: ... a virtual universe into his computer with both positive and negative mass particles, along with his interpretations of Newton’s ... 06:32: Those simulations showed that galaxies do indeed spin more quickly when surrounded by negative mass particles. 06:39: ... is because the positive mass in the galaxy attracts a halo of negative mass, but at the same time ... 06:59: To make the same negative mass stuff also emulate dark energy requires an extra gigantic assumption. 07:07: The problem is that our negative masses will dilute away as the universe expands. 07:12: To fix this, Farnes proposes that these negative masses are constantly created as the universe expands. 07:20: That keeps the density of negative masses constant, even as the density of positive masses falls. 07:26: The result is a very diffuse negative mass fluid that fills the universe and constantly replenishes itself. 08:18: ... analog of Newton’s law of gravity for the whole cosmos, this negative mass fluid – as a negative cosmological constant – has the same competing ... 09:55: Plugging negative masses into general relativity allows you to break causality. 10:07: This is a strong indication that negative mass can’t exist. 12:59: ... confused by the compounding negatives in what is probably not a negative mass, anti-gravitational, positive pressure, anti-deSitter space ... 05:03: Mass determines the strength and direction of the gravitational field – that’s gravitational mass. 05:23: For a positive inertial mass, direction of acceleration is the same as direction as the applied force. 07:26: The result is a very diffuse negative mass fluid that fills the universe and constantly replenishes itself. 08:18: ... analog of Newton’s law of gravity for the whole cosmos, this negative mass fluid – as a negative cosmological constant – has the same competing effects ... 00:32: And it’s pretty wild: negative mass particles continuously popping into existence between the galaxies. 06:15: The author uses these ideas about the interactions of negative and positive mass particles to create an N-body simulation. 06:22: ... a virtual universe into his computer with both positive and negative mass particles, along with his interpretations of Newton’s ... 06:32: Those simulations showed that galaxies do indeed spin more quickly when surrounded by negative mass particles. 00:32: And it’s pretty wild: negative mass particles continuously popping into existence between the galaxies. 06:59: To make the same negative mass stuff also emulate dark energy requires an extra gigantic assumption. 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 04:06: Forgetting that pressure stuff for a moment, positive masses and energies always have a positive gravitational effect. 04:15: So what about negative masses? 04:18: The answer is complicated - it’s not always obvious how weird stuff like negative masses translates from general relativity to Newton’s laws. 04:31: In Newtonian gravity, you multiply the two masses together along with some other stuff to get the strength of their mutual gravitational attraction. 04:40: Two positive masses always give an attractive force by definition. 04:45: Two negative masses should cancel each other’s signs so also give you an attractive force. 05:45: So Farnes argues that the “attractive” gravitational force between two negative masses should actually drive them apart. 07:07: The problem is that our negative masses will dilute away as the universe expands. 07:12: To fix this, Farnes proposes that these negative masses are constantly created as the universe expands. 07:20: That keeps the density of negative masses constant, even as the density of positive masses falls. 09:55: Plugging negative masses into general relativity allows you to break causality. 07:20: That keeps the density of negative masses constant, even as the density of positive masses falls. 04:18: The answer is complicated - it’s not always obvious how weird stuff like negative masses translates from general relativity to Newton’s laws.
	2018-12-20: Why String Theory is Wrong 04:17: It was an incredible discovery and a beautiful one. It even made a prediction: the ratio between the mass of the electric charge and the electron. 04:26: Assuming the experimentally measured value for the electric charge, the corresponding electron mass should be around five kilograms?
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... under reflections are called even things like the energy of the ball its mass the time on its clock and as we'll see angular momentum don't change in ...
	2018-11-21: 'Oumuamua Is Not Aliens 14:31: The rate of oscillation depends on the tiny mass of the neutrino. 14:35: ... matter, interactions with the electromagnetic field change the effect of mass of the neutrino by a process analogous to the refractive index, which ...
	2018-11-14: Supersymmetric Particle Found? 02:41: To solve the hierarchy problem perfectly, those particles would need to have masses at around what we call the electroweak energy. 02:30: ... is that these supersymmetric particles are all expected to be way more massive than their known partners in the standard ... 03:18: It may just be that these new particles are way more massive than expected. 03:27: To detect more massive supersymmetric particles, you need higher energy particle collisions. 02:30: ... is that these supersymmetric particles are all expected to be way more massive than their known partners in the standard ... 03:18: It may just be that these new particles are way more massive than expected. 03:27: To detect more massive supersymmetric particles, you need higher energy particle collisions.
	2018-11-07: Why String Theory is Right 07:42: Finding symmetries can massively reduce the complexity of the math.
	2018-10-31: Are Virtual Particles A New Layer of Reality? 05:18: ... spin, but they don't need to obey Einstein's relationship between energy mass and ... 05:34: They can have any mass. 16:52: They were apparently orbiting a center of mass that wasn't even between the stars.
	2018-10-25: Will We Ever Find Alien Life? 02:42: Life is expected to massively alter the chemical composition of its home world atmosphere. 11:36: Researchers argue that all emerging technological civilizations will go through this phase of massive access to potentially cataclysmic technology. 12:05: But I should also point out that this same massive access to technology that could kill us may also get humanity off the earth and onto other planets. 11:36: Researchers argue that all emerging technological civilizations will go through this phase of massive access to potentially cataclysmic technology. 12:05: But I should also point out that this same massive access to technology that could kill us may also get humanity off the earth and onto other planets. 11:36: Researchers argue that all emerging technological civilizations will go through this phase of massive access to potentially cataclysmic technology. 12:05: But I should also point out that this same massive access to technology that could kill us may also get humanity off the earth and onto other planets. 02:42: Life is expected to massively alter the chemical composition of its home world atmosphere.
	2018-10-18: What are the Strings in String Theory? 00:59: We need to use physical measurement to fix 19 free parameters like the masses of particles. 02:09: ... mesons, as well as an odd relationship between their angular momenta and masses suggested that the quarks in mesons are connected by-- you guessed it-- ... 07:10: Particle mass just comes from the length of the string and its tension. 07:17: String length defines mass, but also defines which complex vibrational modes are possible. 08:13: ... answers include pure mass energy, fundamental irreducible existence, topological irregularities in ... 00:59: We need to use physical measurement to fix 19 free parameters like the masses of particles. 02:09: ... mesons, as well as an odd relationship between their angular momenta and masses suggested that the quarks in mesons are connected by-- you guessed it-- ... 14:03: Roman R. asks whether computation at an event horizon would experience massive time dilation relative to an outside observer. 03:03: And one of those modes appeared to be a massless spin-2 particle. 03:08: But the only hypothetical massless spin-2 particle is the graviton, the conjectured quantum particle of the gravitational field. 10:23: In short, without exactly this number of dimensions, you don't get gravitons or any other massless particle. 03:03: And one of those modes appeared to be a massless spin-2 particle. 03:08: But the only hypothetical massless spin-2 particle is the graviton, the conjectured quantum particle of the gravitational field. 03:03: And one of those modes appeared to be a massless spin-2 particle. 03:08: But the only hypothetical massless spin-2 particle is the graviton, the conjectured quantum particle of the gravitational field.
	2018-10-10: Computing a Universe Simulation 04:38: If we instead count all the elementary particles with mass, we might get 10 to the 81 particles. 05:32: It's directly proportional to its mass. 05:35: The mass of a 100 kilometer radius black hole would be 30 times that of our sun. 05:40: ... a hard drive the size of a picturesque European nation with the mass of the heaviest stars in the universe and with the storage capacity to ... 06:05: You'd need a black hole a few million times the mass of the sun and 10 million kilometers in radius. 06:15: Now those are some big masses from our puny human perspective. 08:04: ... the energy of the system, we use the mass of the observable universe, around 10 to the power of 52 kilograms, and ... 09:03: Instead of using the mass of the universe to figure out the computation speed, we only have 30 solar masses. 06:15: Now those are some big masses from our puny human perspective. 09:03: Instead of using the mass of the universe to figure out the computation speed, we only have 30 solar masses.
	2018-10-03: How to Detect Extra Dimensions 10:20: ... out by looking at other properties of the merger event-- namely, the masses of the merging objects and the frequency of the wave combined with our ...
	2018-09-20: Quantum Gravity and the Hardest Problem in Physics 01:45: In it, the presence of mass and energy warp the fabric of space and time. 08:52: In general relativity, the presence of mass or energy warps the gravitational field. 10:31: ... example, measurement of the mass and charge of an electron renormalizes quantum electrodynamics to allow ... 13:20: A few of you asked why it is that the surface area of a black hole's event horizon must always increase and how mass and radius can actually decrease. 13:35: There's only one place for that energy to come from, the mass of the black holes. 13:39: As a result, the mass of the final merged black hole is smaller than the sum of the masses of the two originals. 13:46: Event horizon radius is proportional to mass. 14:18: The loss of rotational energy by the black hole also means a loss of mass. 13:39: As a result, the mass of the final merged black hole is smaller than the sum of the masses of the two originals. 02:17: Where general relativity describes the universe of the large and the massive, quantum mechanics talks about the subatomic world. 13:54: Note that the final black hole is both more massive and larger than either of the original black holes taken separately. 02:17: Where general relativity describes the universe of the large and the massive, quantum mechanics talks about the subatomic world. 13:54: Note that the final black hole is both more massive and larger than either of the original black holes taken separately. 02:17: Where general relativity describes the universe of the large and the massive, quantum mechanics talks about the subatomic world.
	2018-09-12: How Much Information is in the Universe? 07:48: Sagittarius A star in the center of the Milky Way, which has a mass of four million suns. 09:47: How large a black hole computer would you need in mass and radius to contain enough data to simulate the entire observable universe?
	2018-09-05: The Black Hole Entropy Enigma 02:08: From the point of view of the outside universe, black holes can only have three properties-- mass, spin, and electric charge. 04:59: We can easily measure its mass, spin, and electric charge, and according to the no-hair theorem that's all there is to know. 06:17: They can never shrink in mass or radius. 06:22: If you merge two black holes, some of their mass gets converted to the energy radiated away in gravitational waves. 06:40: Gravitational radiation and the Penrose process reduce black-hole mass and radius or the sum of masses and radii of emerging black holes. 07:10: ... relating the change in black-hole surface area to the change in its mass closely resembles the original definition of thermodynamic ... 07:21: Just replace change in entropy and internal thermal energy with change in black-hole surface area and black-hole mass, respectively. 08:14: The information content of a black hole is proportional not to its mass or radius or volume. 09:04: He showed that black holes radiate random particles exactly as though they have a peak glow for a particular temperature that depends on their mass. 09:26: ... plugged his Hawking temperature into that equation along with black-hole mass for internal energy and figured out the total entropy contained in a ... 07:10: ... relating the change in black-hole surface area to the change in its mass closely resembles the original definition of thermodynamic ... 02:08: From the point of view of the outside universe, black holes can only have three properties-- mass, spin, and electric charge. 04:59: We can easily measure its mass, spin, and electric charge, and according to the no-hair theorem that's all there is to know. 06:40: Gravitational radiation and the Penrose process reduce black-hole mass and radius or the sum of masses and radii of emerging black holes.
	2018-08-30: Is There Life on Mars? 07:31: ... the advent of high-resolution scanning electron microscopy and laser mass ... 09:29: But unexpected cleaning events from the Martian wind cleared those accumulations, allowing the massively extended lifespans of both rovers.
	2018-08-23: How Will the Universe End? 07:06: If protons decay, black holes would be the only mass of bodies left in the universe after 10 to the power 40 years. 07:18: But most of the black hole mass will be in supermassive black holes. 07:30: Some have grown to masses of up to 100 trillion suns, having swallowed good-sized bites from entire galaxy clusters. 07:44: They slowly leak away their mass as a cool heat [INAUDIBLE] of random particles for the most part faint radio light. 07:51: The small black holes, say, around 10 times the mass of the sun, completely evaporate in around 10 to the power of 67 years. 11:07: He figures that the most likely minimum black hole mass is the Planck mass of 20 micrograms. 14:19: If you have your mass and charge distributed exactly the same, then g equals 1. 14:24: If, by contrast, you have an infinitely thin shell of charge surrounding a mass, your g equals 5/3. 14:44: This, in essence, is because his equation has the charge and mass distributed differently. 07:30: Some have grown to masses of up to 100 trillion suns, having swallowed good-sized bites from entire galaxy clusters. 02:32: ... remnants, the ultradense neutron stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including ... 05:49: Around 10 times longer still, and the entire megagalaxy will either have dispersed or fallen into the massive black hole at the galactic center. 02:32: ... remnants, the ultradense neutron stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including ... 05:49: Around 10 times longer still, and the entire megagalaxy will either have dispersed or fallen into the massive black hole at the galactic center. 02:32: ... remnants, the ultradense neutron stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including the ...
	2018-08-15: Quantum Theory's Most Incredible Prediction 04:02: Nonetheless, electrons do have a sort of intrinsic, angular momentum, a fundamental quantum spin that is as intrinsic as mass and charge. 15:24: ... his words, the Carrington event was actually a pair of coronal mass ejections, a lesser one that reached the earth on August 29, 1859, and ... 15:44: It's been speculated that the first coronal mass ejection cleared the way to allow the second one to travel so quickly. 15:24: ... his words, the Carrington event was actually a pair of coronal mass ejections, a lesser one that reached the earth on August 29, 1859, and caused ...
	2018-08-01: How Close To The Sun Can Humanity Get? 01:53: Outbursts from the corona-- coronal mass ejections-- present an existential threat to our civilization. 02:07: ... Earth's protective magnetosphere was disrupted by a massive coronal mass ejection, dubbed the Carrington Event, after British astronomer Richard ... 01:53: Outbursts from the corona-- coronal mass ejections-- present an existential threat to our civilization. 02:07: ... 1859, Earth's protective magnetosphere was disrupted by a massive coronal mass ejection, dubbed the Carrington Event, after British ...
	2018-07-04: Will A New Neutrino Change The Standard Model? 03:02: These have far lower mass, and unlike quarks and leptons, they have no electric charge, hence neutrino or little neutral one. 03:16: An antimatter version of a particle has the same mass and the opposite electric charge. 04:55: That oscillation is what gives these particles their mass. 06:15: If neutrinos gained their mass by the same mechanism as quarks and electrons, that means their chirality oscillates. 06:28: Now, we know that neutrinos have mass due to a completely different type of oscillation. 06:41: ... they can't be moving at the speed of light, which means they must have mass. ... 06:51: ... mass may indicate the existence of the sterile neutrino, but it could also ... 09:17: It would have a relatively low mass at around 1 electronvolt. 09:21: Forgive the particle-physics energy units for mass. 12:14: A few of you wonder whether adding extra mass to Earth from asteroid mining could lead to problems like with our orbit or Earth's gravitational pull. 12:22: So Earth is around 2,000 times more massive than the entire asteroid belt.
	2018-06-27: How Asteroid Mining Will Save Earth 03:24: If an asteroid is massive enough, it will undergo a process called differentiation. 06:27: ... to carry all that return fuel on the initial launch vehicle, you have to massively cut back on the amount of mining equipment, and you also limit what ... 08:45: It was one of the few missions that had a clear track to massive potential profits and saving the planet from asteroid impact. 03:24: If an asteroid is massive enough, it will undergo a process called differentiation. 08:45: It was one of the few missions that had a clear track to massive potential profits and saving the planet from asteroid impact. 06:27: ... to carry all that return fuel on the initial launch vehicle, you have to massively cut back on the amount of mining equipment, and you also limit what ...
	2018-06-20: The Black Hole Information Paradox 00:37: They add to the mass of the black hole. 00:40: And we now know that this mass can escape. 01:54: It states that black holes can only exhibit three properties-- mass, electric charge, and angular momentum. 03:06: And the energy to create those particles must come from the mass of the black hole itself. 03:25: ... though they have a temperature that is inversely proportional to their mass, and the mass of the black hole should be the only thing that determines ... 14:23: They can have any mass, can travel faster than light, and can even travel backwards in time. 01:54: It states that black holes can only exhibit three properties-- mass, electric charge, and angular momentum. 11:11: ... loose thread, a seemingly insignificant quirk in the theory, can lead to massive discoveries and complete reframing of ...
	2018-06-13: What Survives Inside A Black Hole? 01:09: ... properties are mass, electric charge, and angular momentum, or at least this is the ... 01:45: ... student at Princeton when he proposed that no other properties besides mass, electric charge, and angular momentum should emerge from beneath the ... 03:06: So how does mass, electric charge, and angular momentum communicate their influence across the uncrossable horizon? 03:18: Gravity may be caused by mass, but a gravitational field is a very real thing all on its own. 04:00: You could change anything about the Sun other than its mass and the Earth would continue in the same orbit. 04:20: ... the case of the event horizon, the outside universe can't see the mass inside the black hole, but that mass is remembered in the gravitational ... 04:58: ... field added up over an enclosed surface is proportional to the amount of mass and energy contained by that ... 05:12: The mass could all be located at a single point within the surface or could be evenly distributed across that surface. 05:31: That surface remembers the internal mass as though it was spread evenly across the surface. 07:04: It applies to any shaped surface surrounding any shaped mass or charge. 07:15: They are infinite in range and they arise from conserved quantities, namely mass and charge. 07:34: ... forces have infinite range, and so Gauss's law demands that the mass and charge content of any region of space are remembered in the ... 07:50: ... mass and charge are fundamentally conserved quantities, the only way to ... 08:52: In Einstein's general relativity, a spinning mass drags the fabric of space time around with it in a phenomenon known as frame dragging. 09:36: I hope I've given you a sense of why mass, charge, and angular momentum are remembered by the space outside a black hole. 08:52: In Einstein's general relativity, a spinning mass drags the fabric of space time around with it in a phenomenon known as frame dragging. 01:09: ... properties are mass, electric charge, and angular momentum, or at least this is the proposition behind ... 01:45: ... student at Princeton when he proposed that no other properties besides mass, electric charge, and angular momentum should emerge from beneath the event ... 03:06: So how does mass, electric charge, and angular momentum communicate their influence across the uncrossable horizon? 01:09: ... properties are mass, electric charge, and angular momentum, or at least this is the proposition behind the ... 01:45: ... student at Princeton when he proposed that no other properties besides mass, electric charge, and angular momentum should emerge from beneath the event ... 03:06: So how does mass, electric charge, and angular momentum communicate their influence across the uncrossable horizon? 04:20: ... the case of the event horizon, the outside universe can't see the mass inside the black hole, but that mass is remembered in the gravitational field, ... 02:28: ... we can know about the material that went into the black hole are its mass-energy content, electric charge, and angular ... 00:16: ... holes are weird, the result of absolute gravitational collapse of a massive body, a point of hypothetical infinite density surrounded by an event ...
	2018-05-09: How Gaia Changed Astronomy Forever 02:50: Location on this diagram can tell us about a star's mass, size, fusion activity, and even its past and future evolution. 03:06: After which, lower mass stars will become red giants, before leaving behind white dwarf remnants. 09:21: Red dwarfs are just a very low mass stars. 02:50: Location on this diagram can tell us about a star's mass, size, fusion activity, and even its past and future evolution. 03:06: After which, lower mass stars will become red giants, before leaving behind white dwarf remnants. 09:21: Red dwarfs are just a very low mass stars. 10:23: A star that burns twice as bright does burn half as long-- actually, slightly longer-- because that star will have a more massive core. 10:37: Obviously, this is why the more massive Leon beat it before Pris and Roy. 10:23: A star that burns twice as bright does burn half as long-- actually, slightly longer-- because that star will have a more massive core. 10:37: Obviously, this is why the more massive Leon beat it before Pris and Roy. 10:23: A star that burns twice as bright does burn half as long-- actually, slightly longer-- because that star will have a more massive core. 10:37: Obviously, this is why the more massive Leon beat it before Pris and Roy.
	2018-05-02: The Star at the End of Time 02:41: ... known as "M dwarfs." We observe that a red dwarf with 10% of the Sun's mass is about 1,000 times fainter than the ... 03:31: As a result, the Sun will only have access to 10% of its mass for fusion fuel. 03:58: A red dwarf with 10% the Sun's mass has just as much fuel to burn as the Sun does, yet it burns it 1,000 times slower. 07:57: ... wharfs in the middle range of mass, around 15% of the Sun's mass, are predicted to enter a period of ... 09:54: ... of smaller black holes in a shared orbit amounting to the same total mass. ... 02:21: ... the rate of fusion depends very sensitively on temperature, more massive stars with their hotter cores burn through their fuel much, much more ... 02:31: The most massive stars live only a few million years. 02:36: Stars less massive than the Sun burn through their fuel much more slowly. 04:37: An interesting thing about red dwarfs is they don't expand as they brighten, unlike more massive stars. 06:58: As these brighten one by one, the most massive will shine brighter than the current Sun. 02:21: ... the rate of fusion depends very sensitively on temperature, more massive stars with their hotter cores burn through their fuel much, much more ... 02:31: The most massive stars live only a few million years. 02:36: Stars less massive than the Sun burn through their fuel much more slowly. 04:37: An interesting thing about red dwarfs is they don't expand as they brighten, unlike more massive stars. 06:58: As these brighten one by one, the most massive will shine brighter than the current Sun. 02:21: ... the rate of fusion depends very sensitively on temperature, more massive stars with their hotter cores burn through their fuel much, much more ... 02:31: The most massive stars live only a few million years. 04:37: An interesting thing about red dwarfs is they don't expand as they brighten, unlike more massive stars. 02:31: The most massive stars live only a few million years.
	2018-04-25: Black Hole Swarms 00:30: A supermassive black hole-- four million times the mass of our sun-- lurks in the center. 02:37: Even after blowing off most of their mass in a supernova, these black holes are still heavier than most stars. 09:40: Gravitational waves are produced when the quadrupole moment of a mass distribution changes. 09:46: In non-techno speak, they're created in non-spherically or circularly symmetric movements of mass. 09:40: Gravitational waves are produced when the quadrupole moment of a mass distribution changes. 02:11: Black holes form when the most massive stars end their lives in spectacular supernova explosions. 02:16: After blowing off their outer layers, if the remaining stellar core is massive enough, it'll collapse into a black hole. 02:26: ... wave signals detected by LIGO, suggest they may be even more massive. ... 03:12: The key is that the more massive object-- usually, the black hole-- tends to donate its momentum to the less massive object. 04:08: Because globular clusters are much more massive than a single black hole, they reach the galactic center a lot will quickly. 02:11: Black holes form when the most massive stars end their lives in spectacular supernova explosions. 02:16: After blowing off their outer layers, if the remaining stellar core is massive enough, it'll collapse into a black hole. 02:26: ... wave signals detected by LIGO, suggest they may be even more massive. ... 03:12: The key is that the more massive object-- usually, the black hole-- tends to donate its momentum to the less massive object. 04:08: Because globular clusters are much more massive than a single black hole, they reach the galactic center a lot will quickly. 03:12: The key is that the more massive object-- usually, the black hole-- tends to donate its momentum to the less massive object. 02:11: Black holes form when the most massive stars end their lives in spectacular supernova explosions.
	2018-04-18: Using Stars to See Gravitational Waves 00:58: In three cases, both members of the black hole binary pair were well over 20 times the mass of the sun. 01:04: And in the other cases, they were 30 plus solar masses. 01:07: ... we think they must, then they should weigh in at between 5 and 15 solid masses, 20 at ... 02:04: A more recent paper has a very different explanation for the apparent large black hole masses. 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger. 03:49: ... catch the merger of the million to billion solar mass black holes, supermassive black holes that live in the centers of ... 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger. 01:04: And in the other cases, they were 30 plus solar masses. 01:07: ... we think they must, then they should weigh in at between 5 and 15 solid masses, 20 at ... 02:04: A more recent paper has a very different explanation for the apparent large black hole masses. 01:07: ... we think they must, then they should weigh in at between 5 and 15 solid masses, 20 at ... 01:30: Some are trying to adjust stellar evolution models to allow for the formation of more massive black holes. 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger. 03:47: The more massive the binary, the lower the frequency. 05:59: The international pulsar timing array is a massive effort spanning many universities and radio observatories around the world. 01:07: ... if these black holes formed in the deaths of massive stars, which we think they must, then they should weigh in at between 5 ... 01:30: Some are trying to adjust stellar evolution models to allow for the formation of more massive black holes. 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger. 03:47: The more massive the binary, the lower the frequency. 05:59: The international pulsar timing array is a massive effort spanning many universities and radio observatories around the world. 01:30: Some are trying to adjust stellar evolution models to allow for the formation of more massive black holes. 05:59: The international pulsar timing array is a massive effort spanning many universities and radio observatories around the world. 02:27: That could make a binary merger in the 5 to 15 solar mass range look like a much more massive merger. 01:07: ... if these black holes formed in the deaths of massive stars, which we think they must, then they should weigh in at between 5 and 15 ...
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 02:25: That's a massive understatement.
	2018-04-04: The Unruh Effect 01:57: Einstein taught us that an object without mass, like a photon, can only travel at the speed of light and no slower. 02:16: ... with mass can never reach the speed of light, so the world line of a massive ...
	2018-03-28: The Andromeda-Milky Way Collision 00:38: ... and a central bulge that hides a giant black hole that contains the mass of well over 100 million ... 07:22: ... several candidate suns, simulation particles with similar orbits and masses to our sun, and they track their final ... 10:25: ... one thing, there's the consistency of the dark matter mass measurements of galaxies and galaxy clusters from gravitational lensing ... 07:22: ... several candidate suns, simulation particles with similar orbits and masses to our sun, and they track their final ...
	2018-03-21: Scientists Have Detected the First Stars 07:32: And as long as they had the same mass, their speeds would be the same, too. 07:47: ... starting and final heights of the counterweight and projectile and the mass of the counterweight and ...
	2018-03-15: Hawking Radiation 02:15: And so the black hole itself pays the debt by slowly leaking away its mass. 07:47: Black holes should have a heat glow with an apparent temperature that depends on their mass. 09:44: To produce particles with mass, the energy of the radiation has to be high enough to cover the rest mass of the particle. 11:28: How do they end up reducing the black hole's mass, instead of increasing it? 00:50: ... places of extreme density like the dead core of a massive star, space and time could be dragged inwards to create a hole in the ... 07:34: So the more massive the black hole, the longer the wavelength of its radiation. 00:50: ... places of extreme density like the dead core of a massive star, space and time could be dragged inwards to create a hole in the ... 07:34: So the more massive the black hole, the longer the wavelength of its radiation. 00:50: ... places of extreme density like the dead core of a massive star, space and time could be dragged inwards to create a hole in the ... 09:39: By the way, Hawking radiation is mostly going to be photons and other massless particles.
	2018-03-07: Should Space be Privatized? 11:02: [INAUDIBLE] wants to know how the least mass of stars, red dwarfs, die. 12:34: Elementary trebuchets cast a stone of mass 1 at distance 1. 07:03: Massive human effort is wasted every time a large program is scrapped, often for poorly informed political reasons or as publicity stunts.
	2018-02-28: The Trebuchet Challenge 01:36: Of course, that change in speed will be different for objects of different masses. 01:43: ... Newton's laws tell us that when two objects with different masses are accelerated by the same force over the same path, the quantity half ... 02:35: Kinetic and potential energy are defined as combinations of more basic quantities, for example, position, velocity, and mass. 04:39: You want to figure out the speed of impact of a trebuchet projectile based on the mass and the movement of the counterweight. 05:46: We'll also assume that the mass of the lever arm is tiny compared to the mass of the counterweight and the projectile. 05:52: Now, the mass of the lever arm could be included by talking about the change in height of the center of mass of the whole counterweight-arm system. 07:40: It's enough to know the start and end locations of the counterweight and projectile, along with their masses. 01:43: ... are accelerated by the same force over the same path, the quantity half mass times velocity squared has to be ... 01:36: Of course, that change in speed will be different for objects of different masses. 01:43: ... Newton's laws tell us that when two objects with different masses are accelerated by the same force over the same path, the quantity half ... 07:40: It's enough to know the start and end locations of the counterweight and projectile, along with their masses. 03:37: ... is incredibly efficient at converting the potential energy of a massive counterweight into the castle-destroying kinetic energy of a ...
	2018-02-21: The Death of the Sun 01:02: How a star dies depends on its mass. 01:26: Based on its mass, it's expected to have a lifespan of around 10 billion years. 04:27: The core continues to shrink slowly, even as it gains mass from the shell. 05:54: ... it loses mass, its gravitational hold weakens and so the Earth's orbit expands, perhaps ... 09:44: ... asked whether the combination of two particles has a different mass when those particles are close together versus when they're far apart ... 09:57: ... property of mass is just a measure of the energy bound into the system, whether the ... 10:31: The resulting combined nucleus is lighter than the sum of the masses of the two distant protons. 10:40: Does this mean that the combined system of the Earth plus you gains mass every time you jump, because you gain potential energy? 10:31: The resulting combined nucleus is lighter than the sum of the masses of the two distant protons. 01:09: The most massive stars live only for hundreds of thousands to millions of years, and die in spectacular explosions called supernovae. 10:06: ... example, a system of two protons is more massive if the protons are closer together than far apart, because close ... 01:09: The most massive stars live only for hundreds of thousands to millions of years, and die in spectacular explosions called supernovae. 10:06: ... example, a system of two protons is more massive if the protons are closer together than far apart, because close ... 01:09: The most massive stars live only for hundreds of thousands to millions of years, and die in spectacular explosions called supernovae.
	2018-02-14: What is Energy? 01:15: He realized that the sum of mass times velocity squared for a system of particles bouncing around on a flat surface is conserved. 02:47: ... example, du Chatelet's gravitational potential energy, mass times the gravitational acceleration times height, is just a statement ... 06:35: ... in the forces that bind subatomic particles together, the energy of mass, which we talk about in earlier ... 12:58: ... Brockman points out that 15 Earth masses of terrestrial material is a lot a planet for a star to consume, at ... 13:14: In other star systems, we frequently see one or more super-Earths with several Earth masses each. 01:15: He realized that the sum of mass times velocity squared for a system of particles bouncing around on a flat surface is conserved. 02:47: ... example, du Chatelet's gravitational potential energy, mass times the gravitational acceleration times height, is just a statement about ... 01:15: He realized that the sum of mass times velocity squared for a system of particles bouncing around on a flat surface is conserved. 12:58: ... Brockman points out that 15 Earth masses of terrestrial material is a lot a planet for a star to consume, at ... 13:14: In other star systems, we frequently see one or more super-Earths with several Earth masses each.
	2018-01-31: Kronos: Devourer Of Worlds 01:49: ... separations, we can fine-tune our theoretical models of the galactic mass distribution, including the numbers of near-invisible stellar objects ... 06:06: Oh et al. calculated that 15 Earth masses of raw Earth material would produce the observed abundances very nicely. 06:46: 15 Earth masses would about do the trick there as well. 07:57: ... of you mentioned the idea of star lifting, of actually reducing the mass of the sun to reduce its luminosity and, as a side benefit, to ... 01:49: ... separations, we can fine-tune our theoretical models of the galactic mass distribution, including the numbers of near-invisible stellar objects like black holes ... 06:06: Oh et al. calculated that 15 Earth masses of raw Earth material would produce the observed abundances very nicely. 06:46: 15 Earth masses would about do the trick there as well. 01:41: They're so loosely bound that even a small gravitational nudge can break apart the pair, for example, by interacting with other massive objects.
	2018-01-24: The End of the Habitable Zone 01:09: ... by fusion in the core and the gravitational crush of its immense mass. ... 02:17: But with the same mass packed into a smaller volume, the core is under more gravitational pressure than before. 09:06: Unfortunately, it has neither the mass nor the atmosphere needed to retain the released water. 11:31: Actually, now that I think about it, that might mean that you would only see particles whose rest masses are less than the allowed energy. 11:56: If the event horizon swallows one half of a virtual matter anti-matter pair, then how does the black hole lose mass? 12:03: After all, both matter and anti-matter have positive mass. 12:48: And conservation of energy demands that the black hole give up mass. 02:17: But with the same mass packed into a smaller volume, the core is under more gravitational pressure than before. 11:31: Actually, now that I think about it, that might mean that you would only see particles whose rest masses are less than the allowed energy. 06:54: This is happening already but will massively increase as solar radiation rises. 11:41: Of course, you would always see photons because photons are massless.
	2018-01-17: Horizon Radiation 12:46: Neutron stars certainly seem to experience star quakes-- massive releases of energy, as the star's ion crust cracks.
	2018-01-10: What Do Stars Sound Like? 07:11: Those modes allow us to determine fundamental properties like radius, mass, density, and surface gravity. 13:17: ... an effect called relativistic beaming massively amplifies our perceived brightness of the light emitted in the same ...
	2017-12-20: Extinction by Gamma-Ray Burst 01:41: Some of these mass extinctions were due to giant asteroid impact, including the most recent, which wiped out the dinosaurs 65 million years ago. 01:58: However, at least one mass extinction may have been caused by something we'll never have the technology to stop. 02:41: Now, some won't die that way, but any star more than around eight times the Sun's mass will. 05:05: ... alone is enough to cause a mass extinction event, and this could be exacerbated by the global cooling ... 05:47: The same pattern isn't clear for the other mass extinctions. 11:11: So that gives it a mass of around a quarter billion kilograms. 01:58: However, at least one mass extinction may have been caused by something we'll never have the technology to stop. 05:05: ... alone is enough to cause a mass extinction event, and this could be exacerbated by the global cooling triggered by ... 01:41: Some of these mass extinctions were due to giant asteroid impact, including the most recent, which wiped out the dinosaurs 65 million years ago. 05:47: The same pattern isn't clear for the other mass extinctions. 02:34: As many of you know, a supernova is the explosion that follows the catastrophic collapse of a massive star at the end of its life. 03:08: In that case, the powerful magnetic fields can channel the explosion into narrow jets that massively focus and amplify the blast. 07:20: It's a massive star in the last phase of its life, currently blasting off its outer shells into a pinwheel-like nebula. 02:34: As many of you know, a supernova is the explosion that follows the catastrophic collapse of a massive star at the end of its life. 07:20: It's a massive star in the last phase of its life, currently blasting off its outer shells into a pinwheel-like nebula. 02:34: As many of you know, a supernova is the explosion that follows the catastrophic collapse of a massive star at the end of its life. 07:20: It's a massive star in the last phase of its life, currently blasting off its outer shells into a pinwheel-like nebula. 03:08: In that case, the powerful magnetic fields can channel the explosion into narrow jets that massively focus and amplify the blast.
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 09:50: [INAUDIBLE] Leonard asks whether a particle can have momentum higher than its mass times the speed of light. 10:22: That means momentum approaches infinity for any object with mass that's approaching the speed of light. 10:42: In the case of matter, uncertainty in momentum can manifest in both velocity and mass. 10:47: But photons have constant speed and no mass. 09:50: [INAUDIBLE] Leonard asks whether a particle can have momentum higher than its mass times the speed of light.
	2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series 14:32: ... a couple of you pointed out, we already assumed the geckos had zero mass, so who's to say those rare, zero-mass geckos don't have infinite tensile ...
	2017-11-22: Suicide Space Robots 07:13: A large fraction of the spacecraft's mass was a 317 kilogram impactor-- really a robotic probe all on its own.
	2017-11-02: The Vacuum Catastrophe 00:35: Virtual particles appear and vanish from nowhere in seeming violation of our intuitions about the conservation of mass and energy. 09:33: ... be dark matter until it was realized they just don't contain enough mass, nor are they clumpy ... 00:15: There's a massive disagreement between the theoretical and the measured values of the energy of the vacuum. 05:26: It should also massively increase the spatial curvature of the universe. 00:15: There's a massive disagreement between the theoretical and the measured values of the energy of the vacuum. 05:26: It should also massively increase the spatial curvature of the universe.
	2017-10-25: The Missing Mass Mystery 00:41: When we extrapolate observations to the entire observable universe, we find a billion trillion suns worth of mass. 01:52: It comprises 80% of the mass of the universe or around 25% of its total energy content. 03:14: The proportion of hydrogen that ended up getting fused is very dependent on the density of that hydrogen, so the baryonic mass. 03:36: The second way to calculate the expected baryonic mass is with the cosmic microwave background radiation. 05:50: And yet, when we add up the mass from those galaxies, most of the baryonic matter predicted by a theory is missing. 08:01: And so those solitary baryons could add up to more mass than all of the galaxies in the universe. 10:10: ... our predictions for the relative mass in baryons versus dark matter was so wrong, then it would mean the our ... 11:10: Michael asks whether the space containing an intrinsic energy also means that it has intrinsic mass? 09:10: ... structure filaments, which they assumed was between pairs of nearby massive galaxies, the type typically found in giant dark matter ...
	2017-10-19: The Nature of Nothing 05:01: For example, in QFT, virtual particles can have any mass and any speed, including speeds faster than light, and can even travel backwards in time. 06:03: On the other hand, it always takes a baseline chunk of energy to create a gluon, the carrier of the strong nuclear force, because gluons have mass. 05:50: For example, the massless photon can have the tiniest of possible energies.
	2017-10-11: Absolute Cold 10:09: We just know they must be in orbit because their probable masses are large enough that they must be gravitationally bound.
	2017-10-04: When Quasars Collide STJC 00:15: And stellar mass black holes rip neutron stars to shreds. 01:40: They start with masses of up to 10 or so Suns. 01:44: The ones in the course of galaxies contain the mass of a million two billion Suns. 01:59: Did they get most of their mass from eating gas and stars from their surrounding galaxy? 02:55: Quasar is the term for the most powerful AGNs, and they contain SMBHs with up to billions of Suns in mass. 03:03: But lower down the power scale, we have Seyfert galaxies, which typically contain a single SMBH weighing in at millions of solar masses. 08:37: Can't gravitational radiation cause supermassive black holes to merge, just like it does with regular stellar mass black holes? 09:54: However, careful observations of the stars in the galaxy can help us figure out the masses of the black holes and look for signs of galaxy mergers. 11:06: The standard model of particle physics contains 26 independent parameters, things like the coupling constants and the masses of each particle type. 00:15: And stellar mass black holes rip neutron stars to shreds. 08:37: Can't gravitational radiation cause supermassive black holes to merge, just like it does with regular stellar mass black holes? 00:15: And stellar mass black holes rip neutron stars to shreds. 08:37: Can't gravitational radiation cause supermassive black holes to merge, just like it does with regular stellar mass black holes? 01:40: They start with masses of up to 10 or so Suns. 03:03: But lower down the power scale, we have Seyfert galaxies, which typically contain a single SMBH weighing in at millions of solar masses. 09:54: However, careful observations of the stars in the galaxy can help us figure out the masses of the black holes and look for signs of galaxy mergers. 11:06: The standard model of particle physics contains 26 independent parameters, things like the coupling constants and the masses of each particle type. 01:36: Now, we've he talked about the black hole that form in the deaths of massive stars.
	2017-09-28: Are the Fundamental Constants Changing? 01:00: ... that cannot be predicted by that model, only measured-- things like the mass of the electron and the relative strengths of the forces of ... 03:11: The dimensions behind, say, Newton's gravitational constant-- or the mass of the electron-- all have arbitrary human definitions. 10:38: ... variation of other dimensionless constants, such as the proton electron mass ratio, and the more obscure proton gyromagnetic ... 06:37: Remember quasars, insanely luminous maelstrom drums of superheated matter surrounding the most massive black holes in the universe? 08:26: ... Photons from these extremely distant quasars and gas clouds are massively redshifted-- their wavelengths stretched out due to the expansion of the ... 06:37: Remember quasars, insanely luminous maelstrom drums of superheated matter surrounding the most massive black holes in the universe? 08:26: ... Photons from these extremely distant quasars and gas clouds are massively redshifted-- their wavelengths stretched out due to the expansion of the ...
	2017-09-20: The Future of Space Telescopes 05:30: ... you need to double the diameter of the scope, which means the volume and mass, roughly speaking, increased by a factor of ... 07:13: Ways around this are to add a largish lens or mirror to the satellite, but that adds a lot of mass. 05:30: ... you need to double the diameter of the scope, which means the volume and mass, roughly speaking, increased by a factor of ... 08:19: However, it would be able to see x-rays right down to the event horizons of super massive black holes in distant galaxies. 11:52: Feinstein 100 asks whether a black hole forming in the death of a massive star first goes through a neutron star-like phase. 12:42: ... holds this collapse, when they hit neutron degeneracy pressure, the most massive stars don't manage to stop before the core is smaller than its own event ... 08:19: However, it would be able to see x-rays right down to the event horizons of super massive black holes in distant galaxies. 11:52: Feinstein 100 asks whether a black hole forming in the death of a massive star first goes through a neutron star-like phase. 12:42: ... holds this collapse, when they hit neutron degeneracy pressure, the most massive stars don't manage to stop before the core is smaller than its own event ... 08:19: However, it would be able to see x-rays right down to the event horizons of super massive black holes in distant galaxies. 11:52: Feinstein 100 asks whether a black hole forming in the death of a massive star first goes through a neutron star-like phase. 12:42: ... holds this collapse, when they hit neutron degeneracy pressure, the most massive stars don't manage to stop before the core is smaller than its own event ...
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 02:06: A remnant core between 1.4 and around 3 times the mass of our sun instead ends up as a neutron star. 02:14: These insane objects carry the mass of a star within a sphere the size of a city, around 18 kilometers in diameter. 04:00: See, black holes only form in the deaths of the most massive stars, those over approximately 20 times the Sun's mass. 04:12: Neutron stars form from the not quite as rare stars of around 8 to 20 solar masses. 04:30: Well, again, it's because of mass. 04:32: The remnant core of a dead star must be less than 3 solar masses to make a neutron star. 04:39: But that's a factor of 10 smaller than the 30 solar mass black holes that merged in the first LIGO detection. 04:46: Smaller mass means weaker gravitational waves. 09:32: Seeing a gravitational wave signal from merging neutron stars would allow us to determine pretty exactly how much mass is lost in the merger. 11:05: ... one that may have birthed a new black hole and created half the Earth's mass in ... 04:39: But that's a factor of 10 smaller than the 30 solar mass black holes that merged in the first LIGO detection. 04:12: Neutron stars form from the not quite as rare stars of around 8 to 20 solar masses. 04:32: The remnant core of a dead star must be less than 3 solar masses to make a neutron star. 01:54: When a massive star ends its life in a supernova explosion, it leaves behind an ultra dense core. 02:00: For the most massive stars, that core will collapse into a black hole. 04:00: See, black holes only form in the deaths of the most massive stars, those over approximately 20 times the Sun's mass. 08:03: We rarely see supernovae from this galaxy type because their most massive stars have long since exploded to leave neutron stars and black holes. 01:54: When a massive star ends its life in a supernova explosion, it leaves behind an ultra dense core. 02:00: For the most massive stars, that core will collapse into a black hole. 04:00: See, black holes only form in the deaths of the most massive stars, those over approximately 20 times the Sun's mass. 08:03: We rarely see supernovae from this galaxy type because their most massive stars have long since exploded to leave neutron stars and black holes. 01:54: When a massive star ends its life in a supernova explosion, it leaves behind an ultra dense core. 02:00: For the most massive stars, that core will collapse into a black hole. 04:00: See, black holes only form in the deaths of the most massive stars, those over approximately 20 times the Sun's mass. 08:03: We rarely see supernovae from this galaxy type because their most massive stars have long since exploded to leave neutron stars and black holes.
	2017-08-30: White Holes 02:31: ... solved its equations for a very particular case-- a single point of mass in an otherwise empty space ... 03:49: Now, a real black hole forms from the gravitational collapse of a massive star's core.
	2017-08-24: First Detection of Life 06:11: Of course, these revealed strangely green land masses due to chlorophyll absorbing red light and reflecting green light.
	2017-08-10: The One-Electron Universe 00:33: The fateful conversation began, Feynman, I know why all electrons have the same charge and the same mass. 02:04: ... that they are all identical, exactly the same charge, exactly the same mass, exactly the same ... 06:22: ... useful in simplifying quantum field theory calculations, because it massively cuts down the number of Feynman diagrams you ...
	2017-08-02: Dark Flow 03:39: ... the most massive galaxy clusters in our universe are vast conglomerations of thousands of ... 07:19: We already know that there's something very massive in that direction. 03:39: ... the most massive galaxy clusters in our universe are vast conglomerations of thousands of ... 07:19: We already know that there's something very massive in that direction. 03:39: ... the most massive galaxy clusters in our universe are vast conglomerations of thousands of ...
	2017-07-26: The Secrets of Feynman Diagrams 05:45: We say that these particles are on the mass shell, or just on shell. 05:51: They sit on the shell structure you get when you plot Einstein's equation of energy, momentum, and mass. 05:45: We say that these particles are on the mass shell, or just on shell. 05:41: And they obey Einstein's mass-energy equation. 06:37: These particles do not obey mass-energy equivalence. 05:41: And they obey Einstein's mass-energy equation. 06:37: These particles do not obey mass-energy equivalence. 05:41: And they obey Einstein's mass-energy equation. 06:37: These particles do not obey mass-energy equivalence.
	2017-07-19: The Real Star Wars 07:09: ... US in 1967, prohibits signatories from placing nukes or other weapons of mass destruction in orbit or on a celestial ... 14:51: ... noticed that the theoretical electron mass going to infinity sounds a lot like the ultraviolet catastrophe of the ... 15:20: Nicholas Aiello asks if it's possible that electrons have no fundamental mass and are made up entirely of self energy. 15:30: The so-called bare mass of an electron comes from its interaction with the Higgs field. 15:56: ... mass comes from its interaction with other fields, be it the Higgs field for ... 07:09: ... US in 1967, prohibits signatories from placing nukes or other weapons of mass destruction in orbit or on a celestial ... 01:00: One in which the space around the Earth became highly militarized and, in fact, massively weaponized. 11:00: One, the resulting debris massively increased the amount of space junk in low-Earth orbit. 01:00: One in which the space around the Earth became highly militarized and, in fact, massively weaponized. 11:00: One, the resulting debris massively increased the amount of space junk in low-Earth orbit. 01:00: One in which the space around the Earth became highly militarized and, in fact, massively weaponized.
	2017-07-12: Solving the Impossible in Quantum Field Theory 08:45: This impedes the electron's motion and actually increases its effective mass. 08:54: ... if you try to calculate the self-energy correction to an electron's mass using quantum electrodynamics, you get that the electron has infinite ... 09:07: ... calculate the mass correction due to one of these self-energy loops, you need to add up all ... 09:44: ... electrons do not have infinite mass, and we know that because we've measured that mass, although any ... 10:05: ... of trying to start with the unmeasurable fundamental mass of the electron and solve the equations from there, you fold in a term ... 09:07: ... calculate the mass correction due to one of these self-energy loops, you need to add up all possible ...
	2017-06-28: The First Quantum Field Theory 13:44: In fact, Schrodinger followed the same approach, starting with Einstein's mass energy momentum equation.
	2017-06-21: Anti-Matter and Quantum Relativity 07:52: It would have inertia, acting like it had the mass of the missing electron. 08:03: ... in, annihilating both, and releasing all of the energy bound up in their masses. ... 10:27: Just as with the holes in the Dirac sea, anti-matter particles have the same mass as their counterparts, but opposite charge. 10:35: That mass is very real. 10:37: It's not negative mass despite this negative energy description. 08:03: ... in, annihilating both, and releasing all of the energy bound up in their masses. ...
	2017-05-31: The Fate of the First Stars 01:47: The sun is a population one star, meaning 2% to 3% of its mass is metals. 03:31: But stars of the sun's mass and higher that formed over 13 billion years ago, near the beginning of the universe, would now be long gone. 04:05: One might think that having more mass-- more hydrogen to fuse in their cores-- would allow a star to burn longer. 04:20: OK, physics time-- the cores of stars are under extreme pressure due to the gravitational crush of their great mass. 04:28: The more mass, the greater the pressure. 04:49: A small increase in mass means a small increase in core temperature. 04:58: A star 10 times the mass of the sun shines around 10,000 times brighter. 05:15: ... the smallest population three stars would have had masses of at least several times that of the sun, while the largest would have ... 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses. 05:33: With masses that high, all population three stars would have gone supernova while the universe was still in its infancy. 08:57: In fact, it may be that stars greater than around 250 solar masses can collapse directly into a black hole without exploding. 09:04: ... would merge into monsters of thousands or tens of thousands of solar masses. ... 09:15: ... supermassive black holes, with millions to billions of times the mass of the sun, that we find lurking in the centers of ... 05:15: ... the smallest population three stars would have had masses of at least several times that of the sun, while the largest would have ... 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses. 05:33: With masses that high, all population three stars would have gone supernova while the universe was still in its infancy. 08:57: In fact, it may be that stars greater than around 250 solar masses can collapse directly into a black hole without exploding. 09:04: ... would merge into monsters of thousands or tens of thousands of solar masses. ... 03:25: Star lifespan gets shorter the more massive the spar. 03:59: Massive stars live fast, die young, and leave beautiful space-time warping corpses. 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses. 05:40: So why do we think the first stars were so massive? 03:25: Star lifespan gets shorter the more massive the spar. 03:59: Massive stars live fast, die young, and leave beautiful space-time warping corpses. 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses. 05:40: So why do we think the first stars were so massive? 05:26: By comparison, the most massive lighter stars are, at most, a couple of hundred solar masses. 03:59: Massive stars live fast, die young, and leave beautiful space-time warping corpses. 04:34: So the cores of very massive stars are much hotter than our suns-- up to a couple hundred million Kelvin, versus the sun's 15 million K. 03:59: Massive stars live fast, die young, and leave beautiful space-time warping corpses.
	2017-05-17: Martian Evolution 03:36: We know that the zero-G experienced in orbital or interplanetary space leads to decreased bone density and muscle mass in astronauts. 03:58: ... will be for people with especially strong bones and high muscle mass, people who can afford a little strength loss and still be ... 05:13: After long zero-G missions, astronauts lose significant muscle mass in their hearts. 03:58: ... will be for people with especially strong bones and high muscle mass, people who can afford a little strength loss and still be ... 08:16: This results in a massive selection pressure to keep our immune system up to date.
	2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson 14:09: ... deterministic universe, there's a pseudo randomness that arises due to massive complexity, say, in a room full of 10 to the power of 28 ...
	2017-04-26: Are You a Boltzmann Brain? 07:17: Such systems should massively outnumber larger, big-bang collapses.
	2017-04-19: The Oh My God Particle 03:31: Higher energy cosmic rays tend to obliterate themselves several kilometers above the ground in massive collisions with nuclei of air molecules.
	2017-04-10: Here's Why I Love PBS 00:00: ... is Matt from "Space Time." As a lot of you know, there is a proposal to massively cut the funding to a number of government agencies that provide critical ...
	2017-04-05: Telescopes on the Moon 04:37: ... it's relatively short roll on the lunar surface, Yutu was experiencing a massive temperature differential between its sunny side and shaded ...
	2017-03-29: How Time Becomes Space Inside a Black Hole 06:00: It becomes slightly tilted in the direction of that mass. 05:56: Close to a massive object, your future is no longer at right angles to space.
	2017-03-01: The Treasures of Trappist-1 01:11: The star, TRAPPIST-1a, is an ultra cool dwarf star, about 10% the sun's diameter and less than 10% its mass. 01:52: The gravitational influence on each other allows us to figure out their masses, between 0.4 and 1.4 times Earth's mass. 05:53: Out here on Earth, our distance and our magnetosphere protect us from most of the sun's coronal mass ejections. 07:35: Tidal force between two bodies is proportional to the product of the masses and the inverse cube of their distance. 07:42: ... is so much more mass in the TRAPPIST-1 star planet system than the Jupiter-Io-Europa system ... 10:41: SS asks about the distinction between the genes mass, the genes length, and the genes instability. 10:48: ... in the original derivation by genes, the gene's mass is just the mass of a region of size equal to the gene's length, which ... 11:07: But the gene's mass could also be derived by a simple energy balance. 11:18: But at larger masses, the gravity wins and a star forms. 05:53: Out here on Earth, our distance and our magnetosphere protect us from most of the sun's coronal mass ejections. 01:52: The gravitational influence on each other allows us to figure out their masses, between 0.4 and 1.4 times Earth's mass. 07:35: Tidal force between two bodies is proportional to the product of the masses and the inverse cube of their distance. 11:18: But at larger masses, the gravity wins and a star forms. 10:33: However, Galileo did make massive improvements in the design and effectively invented the use of telescopes for astronomy.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 02:17: Cold and adrift, the mostly hydrogen gas yields to gravity once it reaches the critical Jeans mass. 03:46: Eventually, the growing rock has enough mass to attract material through its own gravity. 03:57: By the time it's at least 10% of the Earth's mass, it will have cleared its orbit of other planetesimals, and will have rounded out into a planet. 06:19: It's bright enough to be a few times Jupiter's mass. 07:34: ... been enough resources to build a planet even at the lower end of Dagon's mass estimate, at around three earth ... 00:44: Fomalhaut is an A-type star about twice as massive and much hotter and brighter than the sun. 07:48: ... some critical point, it may have interacted with another massive planet in the system, sending that planet spiraling closer to Fomalhaut ... 00:44: Fomalhaut is an A-type star about twice as massive and much hotter and brighter than the sun. 07:48: ... some critical point, it may have interacted with another massive planet in the system, sending that planet spiraling closer to Fomalhaut ...
	2017-02-15: Telescopes of Tomorrow 11:39: ... I depicted on the space-time diagram and the geometry that comes from mass and energy-curving ... 11:53: There's no mass or energy warping it. 09:06: ... fluctuate due to the changing gravitational effect of nearby massive ...
	2017-02-02: The Geometry of Causality 07:03: This transformation allows you to calculate how properties, like distance, time, velocity, even mass and energy, shift between reference frames. 14:39: Well, the answer is probably very large, but nowhere near the mass of the SMBHs that we see today. 14:54: ... insanely large first generation of stars, perhaps thousands of times the mass of the ... 15:05: But by now, some of those have grown to billions of times the mass of the sun.
	2017-01-25: Why Quasars are so Awesome 01:05: They have a supermassive black hole, millions to billions of times the mass of the sun. 03:59: Take a black hole of millions to billions of times the mass of the sun. 07:43: The birth of large numbers of new stars is always quickly followed by the explosive deaths of the most massive, shortest lived of those stars.
	2017-01-19: The Phantom Singularity 00:39: Newton's equation gives you the gravitational force exerted between two masses, m1 and m2 that are a distance R apart. 00:53: It means the force gets larger the closer the masses are to each other. 01:21: According to Newton's law, in order to fuel that infinite gravitational acceleration you need to get zero distance from an object's center of mass. 01:30: That means all of that object's mass would need to be concentrated at that center, a single point of 0 size, which means infinite density. 04:45: ... Einstein field equations for the simple case of a spherically symmetric mass in an otherwise empty ... 06:24: Oh, and r subscript s is a measure of the mass of the massive object. 06:30: In fact, it's 2 times the gravitational constant times the mass. 06:47: r, the distance to the center of mass, remains in the denominator just as it was in Newton's law. 07:31: See, when distance to the center of mass is exactly equal to this rs thing, then rs over r is equal to 1. 06:47: r, the distance to the center of mass, remains in the denominator just as it was in Newton's law. 00:39: Newton's equation gives you the gravitational force exerted between two masses, m1 and m2 that are a distance R apart. 00:53: It means the force gets larger the closer the masses are to each other. 00:39: Newton's equation gives you the gravitational force exerted between two masses, m1 and m2 that are a distance R apart. 04:56: We're going to simplify it to only allow movement directly towards or away from our massive object. 05:17: The Schwarzschild metric allows us to compare two points or events in space time around a massive object from the perspective of different observers. 05:37: That motion is towards or away from the massive object, which is a distance r away. 06:24: Oh, and r subscript s is a measure of the mass of the massive object. 04:56: We're going to simplify it to only allow movement directly towards or away from our massive object. 05:17: The Schwarzschild metric allows us to compare two points or events in space time around a massive object from the perspective of different observers. 05:37: That motion is towards or away from the massive object, which is a distance r away. 06:24: Oh, and r subscript s is a measure of the mass of the massive object. 04:56: We're going to simplify it to only allow movement directly towards or away from our massive object. 05:17: The Schwarzschild metric allows us to compare two points or events in space time around a massive object from the perspective of different observers. 05:37: That motion is towards or away from the massive object, which is a distance r away. 06:24: Oh, and r subscript s is a measure of the mass of the massive object.
	2017-01-11: The EM Drive: Fact or Fantasy? 02:19: ... they have to carry not just an energy source, but propellant, a bunch of mass to shoot out the back end to push them ...
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 01:43: At around 15 times the mass of the sun, the dark object in this system can't be anything but a black hole. 02:24: These orbits tell us that a dark something of around four million solar masses lurks in the center. 05:12: It has enough energy to produce a black hole with a mass of 100,000 suns and an event horizon that almost reaches the moon's orbit. 09:23: The Dyson sphere absorbs all of the energy from the shell, so it immediately gains the entire mass equivalence, 100,000 suns worth. 09:53: ... that the original mass of the sphere isn't going to add enough to the 100,000 suns of the near ... 09:23: The Dyson sphere absorbs all of the energy from the shell, so it immediately gains the entire mass equivalence, 100,000 suns worth. 02:24: These orbits tell us that a dark something of around four million solar masses lurks in the center.
	2016-12-14: Escape The Kugelblitz Challenge 02:06: The larger the mass of the collapsing object, the larger this radius. 04:53: The Schwarchild radius of a black hole with this mass is about one light second. 05:22: ... tells us that the entire inside of a spherically symmetric shell of mass or energy feels no gravitational force from that ... 06:04: It would completely absorb the incoming pulse, storing it as a ridiculous amount of electrical energy and the accompanying increase in mass. 04:47: This blast has a mass-energy equivalence of 100,000 suns. 01:35: A black hole forms when the core of a very massive star collapses under its own gravity at the end of a star's life.
	2016-12-08: What Happens at the Event Horizon? 03:16: ... mass of the black hole stretches space and time so that light rays appear to ...
	2016-11-30: Pilot Wave Theory and Quantum Realism 13:34: In that case, any mass of strange quarks will decay into the lighter up or down quarks. 14:51: ... mixed in with the neutrons, perhaps up to 10% electrons and protons by mass of the ...
	2016-11-16: Strange Stars 06:51: It could be that neutron stars have an electroweak core, an apple-sized ball with the mass of two Earths in which quarks themselves burn. 08:32: As down quarks flip into the more massive strange quarks, they have to absorb energy from somewhere to provide for that extra mass. 08:48: Some appear a little bit too small for their mass, suggesting quark matter densities. 00:44: The most wonderfully monstrous of these are the remnant corpses of the most massive stars, stellar zombies like neutron stars and black holes. 01:08: ... save a neutron star from collapse, but ultimately also doom the most massive to collapse into a black ... 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies. 08:32: As down quarks flip into the more massive strange quarks, they have to absorb energy from somewhere to provide for that extra mass. 09:17: ... dying star shouldn't have been massive enough to leave a black hole, yet astronomers still haven't found the ... 00:44: The most wonderfully monstrous of these are the remnant corpses of the most massive stars, stellar zombies like neutron stars and black holes. 01:08: ... save a neutron star from collapse, but ultimately also doom the most massive to collapse into a black ... 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies. 08:32: As down quarks flip into the more massive strange quarks, they have to absorb energy from somewhere to provide for that extra mass. 09:17: ... dying star shouldn't have been massive enough to leave a black hole, yet astronomers still haven't found the ... 00:44: The most wonderfully monstrous of these are the remnant corpses of the most massive stars, stellar zombies like neutron stars and black holes. 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies. 08:32: As down quarks flip into the more massive strange quarks, they have to absorb energy from somewhere to provide for that extra mass.
	2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers 00:53: Thouless, Kosterlitz, and Haldane massively advanced our understanding of these quantum phases by showing how topology drives this weird behavior.
	2016-10-19: The First Humans on Mars 05:43: ... know that astronauts lose around 2% of bone mass per month in zero G. It's surely less on the surface of Mars, but we ... 09:36: Black holes exhibit only three properties-- mass, electric charge, and spin. 09:47: Mass is one way to identify a primordial black hole from a stellar black hole. 09:52: A star's core needs to be more massive than around three times the mass of the sun in order to collapse into a black hole. 10:07: They could in principle be any mass. 10:54: ... tricky to explain how they got that big if they grew from only stellar mass black ... 09:36: Black holes exhibit only three properties-- mass, electric charge, and spin. 09:13: Several of you asked how to tell the difference between a primordial black hole and a black hole formed when a very massive star ends its life. 09:52: A star's core needs to be more massive than around three times the mass of the sun in order to collapse into a black hole. 10:09: ... may tell us that it was impossible for them to have been produced by massive stars, which are rare, as far as stars ... 09:13: Several of you asked how to tell the difference between a primordial black hole and a black hole formed when a very massive star ends its life. 09:52: A star's core needs to be more massive than around three times the mass of the sun in order to collapse into a black hole. 10:09: ... may tell us that it was impossible for them to have been produced by massive stars, which are rare, as far as stars ... 09:13: Several of you asked how to tell the difference between a primordial black hole and a black hole formed when a very massive star ends its life. 10:09: ... may tell us that it was impossible for them to have been produced by massive stars, which are rare, as far as stars ...
	2016-10-12: Black Holes from the Dawn of Time 00:35: As long as a volume of space contains a high enough density of mass or energy, general relativity tells us that a black hole will form. 03:29: Now, these models can predict a huge range of possible masses for primordial black holes-- PBHs, as we like to call them in the biz. 03:39: PBHs could have been formed at a few grams to tens of thousands of times the mass of the sun, depending on which formation model you go with. 03:52: If they do exist, then there's probably a particular mass range that most of them formed at. 03:57: Discovering PBHs and learning their masses would tell us a huge amount about the earliest moments of our universe. 04:10: First of all, we aren't going to find primordial black holes less than around a billion tons, or the mass of a small asteroid. 04:48: This is a slightly terrifying possibility that 80% of the mass in the universe is in the form of countless, swarming black holes. 05:21: Depending on PBH mass, this would cause a twinkling effect-- microlensing. 05:32: Well we just don't see enough of this twinkling, which rules out a lot of possible masses. 06:07: These arguments let us rule out all but a very narrow set of mass ranges for primordial black holes as an explanation for dark matter. 06:17: ... options we're left with are either lots of PBHs with masses similar to a large asteroid like Ceres, so around 10 to the power of 21 ... 06:59: With new observations from both regular telescopes and LIGO, we're rapidly closing all of these mass windows. 07:07: ... long, we'll either spot the signature of primordial black holes at these masses, or discover that PBHs are actually very rare, and that they're certainly ... 08:36: Having high mass primordial black holes just makes it more likely. 08:40: If PBHs are closer to the mass of a large asteroid, then they're too low in mass and probably moving too fast to do any gravitational damage. 09:11: ... if primordial black holes have approximately the minimum possible mass to not have evaporated-- around a billion tons-- these would be much ... 08:36: Having high mass primordial black holes just makes it more likely. 03:52: If they do exist, then there's probably a particular mass range that most of them formed at. 06:07: These arguments let us rule out all but a very narrow set of mass ranges for primordial black holes as an explanation for dark matter. 06:59: With new observations from both regular telescopes and LIGO, we're rapidly closing all of these mass windows. 03:29: Now, these models can predict a huge range of possible masses for primordial black holes-- PBHs, as we like to call them in the biz. 03:57: Discovering PBHs and learning their masses would tell us a huge amount about the earliest moments of our universe. 05:32: Well we just don't see enough of this twinkling, which rules out a lot of possible masses. 06:17: ... options we're left with are either lots of PBHs with masses similar to a large asteroid like Ceres, so around 10 to the power of 21 ... 07:07: ... long, we'll either spot the signature of primordial black holes at these masses, or discover that PBHs are actually very rare, and that they're certainly ... 00:49: That's in the core of the most massive stars when they die. 08:07: Even a close encounter with a black hole as massive as the Sun or higher would be pretty catastrophic. 00:49: That's in the core of the most massive stars when they die. 08:07: Even a close encounter with a black hole as massive as the Sun or higher would be pretty catastrophic. 00:49: That's in the core of the most massive stars when they die.
	2016-09-29: Life on Europa? 02:49: The same forces drive massive volcanic activity in its system moon IO, and so it's likely that Europa's rocky interior is also geologically active.
	2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer 01:09: It's as though something with a mass energy equivalence of 17 MEV was decaying into those particles.
	2016-08-24: Should We Build a Dyson Sphere? 03:45: Mercury is ideal, because it has a gigantic solid iron core, comprising over 40% of the planet's mass. 06:39: Only 0.7% of the rest mass of the ingoing hydrogen fuel at the sun's core is converted to energy. 07:00: What if instead of converting 0.7% of fuel rest mass into energy we could achieve 100% efficiency? 07:54: ... is really 100% efficient conversion of mass into energy, assuming we can find a way to pump new matter into the ... 08:24: And also Kugelblitz and other 100% efficient mass converters are indefinitely scalable. 08:37: However, there's enough mass in the solar system to run a type 3 civilization's Kugelblitz swarm for many times the current age of the universe. 08:24: And also Kugelblitz and other 100% efficient mass converters are indefinitely scalable.
	2016-08-10: How the Quantum Eraser Rewrites the Past 11:08: And they're at least several times the mass of the sun. 11:37: These may have masses similar to planets rather than stars, if they exist.
	2016-08-03: Can We Survive the Destruction of the Earth? ft. Neal Stephenson 01:08: There have been at least five mass extinctions over the past 500 million years. 06:02: Any asteroid or comet bigger than a few kilometers diameter has the potential to cause extreme climate change and mass extinction. 06:42: ... of the other cataclysms that may have caused previous mass extinctions will probably give us at least some warning and are somewhat ... 12:49: ... 100 times smaller than the Planck length for anything within a human's mass, getting double-slit interference for something truly macroscopic is ... 06:02: Any asteroid or comet bigger than a few kilometers diameter has the potential to cause extreme climate change and mass extinction. 01:08: There have been at least five mass extinctions over the past 500 million years. 06:42: ... of the other cataclysms that may have caused previous mass extinctions will probably give us at least some warning and are somewhat easier to ... 01:30: ... others may have been due to massive bursts of volcanism, leaps in evolution overturning the biosphere's ... 06:51: For example, massive volcanism doesn't just happen. 08:58: ... a very massive star goes supernova, the resulting collapse of the core into a neutron ... 12:14: vhsjpdfg inquires after the wave functions and interference patterns for massive objects. 01:30: ... others may have been due to massive bursts of volcanism, leaps in evolution overturning the biosphere's ... 06:51: For example, massive volcanism doesn't just happen. 08:58: ... a very massive star goes supernova, the resulting collapse of the core into a neutron ... 12:14: vhsjpdfg inquires after the wave functions and interference patterns for massive objects. 01:30: ... others may have been due to massive bursts of volcanism, leaps in evolution overturning the biosphere's ... 12:14: vhsjpdfg inquires after the wave functions and interference patterns for massive objects. 08:58: ... a very massive star goes supernova, the resulting collapse of the core into a neutron star, ... 06:51: For example, massive volcanism doesn't just happen.
	2016-07-27: The Quantum Experiment that Broke Reality 11:18: ... Blank asks, "Wasn't Jupiter almost a star?" Well, the lowest mass stars are around 7.5% the mass of the Sun, while Jupiter is 1/10,000 of ... 11:55: There's a minimum mass that's capable of doing that. 11:58: It's called "the Jeans mass." It depends on cloud size, temperature, rotation rate, and composition. 12:04: For typical interstellar clouds, the Jeans mass is quite a bit smaller than the Sun's mass but still much, much larger than Jupiter's. 11:18: ... Blank asks, "Wasn't Jupiter almost a star?" Well, the lowest mass stars are around 7.5% the mass of the Sun, while Jupiter is 1/10,000 of a ... 11:45: Well, the Sun and other stars don't need rocky cores because they are massive enough for all of that gas to collapse by itself.
	2016-07-20: The Future of Gravitational Waves 00:43: These oscillations echoed the final 1/10 of a second of the end spiral and merger of a pair of black holes, each around 30 times the mass of the Sun. 01:14: This time, they're a bit smaller, at 14 and eight solar masses. 04:20: We also now know that our estimates of the number of binary black holes in the universe and their masses are at least in the right ballpark. 01:14: This time, they're a bit smaller, at 14 and eight solar masses. 04:20: We also now know that our estimates of the number of binary black holes in the universe and their masses are at least in the right ballpark. 05:25: When European Virgo comes online later this year, we expect a massive improvement in our ability to locate the source of the waves.
	2016-07-06: Juno to Reveal Jupiter's Violent Past 00:37: It may only have 1,000th of the sun's mass, but it weighs more than all the other planets combined, two and 1/2 times more. 01:22: ... grew to at least 10 and maybe over 40 times the mass of the Earth before it had enough gravity to start holding on to the ... 01:36: That solid core now comprises, at most, 15% of the planet's mass. 02:51: The center of mass of the sun-Jupiter system lies just above the solar surface, and both the sun and Jupiter circle this point. 06:15: ... should also have formed another massive planet, at least half of Earth's mass in Mars's ... 06:28: But Mars is a measly 10% of Earth's mass. 06:43: Another clue is that other real exoplanetary systems tend to have super Earths, rocky planets several times the mass of our own planet. 01:22: ... before it had enough gravity to start holding on to the 300-ish Earth masses of hydrogen and helium that make up most of the planet ... 00:32: It's by far the largest and most massive thing in our solar system after the sun. 06:15: ... disk capable of forming Venus and Earth should also have formed another massive planet, at least half of Earth's mass in Mars's ... 08:51: This is hypothesized to have caused the massive meteor activity of the late heavy bombardment, re-liquefying Earth's newly solidified crust. 00:32: It's by far the largest and most massive thing in our solar system after the sun. 06:15: ... disk capable of forming Venus and Earth should also have formed another massive planet, at least half of Earth's mass in Mars's ... 08:51: This is hypothesized to have caused the massive meteor activity of the late heavy bombardment, re-liquefying Earth's newly solidified crust. 06:15: ... disk capable of forming Venus and Earth should also have formed another massive planet, at least half of Earth's mass in Mars's ... 00:32: It's by far the largest and most massive thing in our solar system after the sun.
	2016-06-29: Nuclear Physics Challenge 02:27: ... relationship, which relates the radius of the nucleus to the atomic mass ... 02:56: And you can calculate the velocity using the equation for kinetic energy and the mass of the alpha particle. 02:27: ... relationship, which relates the radius of the nucleus to the atomic mass number. ...
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 12:22: Also, the lens mass distribution is never perfectly circularly symmetric around its axis. 13:13: ... Palmer would like to know how we can really be confident measuring the mass of a gravitational lens, given we don't really know the composition of ... 13:34: ... from redshift, then you can explore an enormous range of possible lens mass distributions with computer ... 13:54: That set will span a range of masses, but that range is usually pretty small. 13:59: So we end up with a best mass and error bars defined by that range. 12:22: Also, the lens mass distribution is never perfectly circularly symmetric around its axis. 13:34: ... from redshift, then you can explore an enormous range of possible lens mass distributions with computer ... 13:54: That set will span a range of masses, but that range is usually pretty small.
	2016-06-15: The Strange Universe of Gravitational Lensing 01:27: ... that only resembles our mind's eye Euclidean lattice in the absence of mass and ... 01:41: The curvature produced by mass gives gravity. 04:19: Find that configuration, and we've mapped the gravitational field, the distribution of mass of the lens. 04:31: And we've confirmed that the vast majority of mass in this universe is in the form of dark matter. 02:57: The gravitational field of any massive object converges passing light rays, like a badly designed lens.
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 01:51: We only know they ever existed because the resulting gamma radiation has an energy corresponding to the mass of the decayed particle. 02:17: This suggests a new particle with a mass much larger than anything in the standard model. 04:03: Just like the proton is a combination of three quarks, this could be a much more massive combination of several quarks and antiquarks. 08:40: Most of those same organisms went extinct due to sudden and massive environmental changes, probably including climate change due to meteor impact. 04:03: Just like the proton is a combination of three quarks, this could be a much more massive combination of several quarks and antiquarks. 08:40: Most of those same organisms went extinct due to sudden and massive environmental changes, probably including climate change due to meteor impact. 04:03: Just like the proton is a combination of three quarks, this could be a much more massive combination of several quarks and antiquarks. 08:40: Most of those same organisms went extinct due to sudden and massive environmental changes, probably including climate change due to meteor impact.
	2016-06-01: Is Quantum Tunneling Faster than Light? 02:23: See an object's de Broglie wavelength depends on its momentum, so mass times velocity.
	2016-05-25: Is an Ice Age Coming? 00:30: ... geological period is the Quaternary, and is characterized by a massive glaciation-- vast ice sheets stretching from the Arctic all the way down ...
	2016-05-18: Anti-gravity and the True Nature of Dark Energy 04:18: In general relativity, energy slash mass and pressure both curve space time. 05:39: ... ultimate effect is that the massive of a region of the universe is higher if its particles are moving ...
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 03:33: The basic concept is the same-- an extremely low mass laser powered light sail. 03:38: The main innovation of the Starshot is that it's not just low mass, it is ultra low mass, weighing in at grams rather than Starwisp's kilograms. 04:41: The ultra low mass means that the nanocraft can be accelerated to a decent clip with a giant laser that we could plausibly build in a generation. 07:00: It's assumed that processor size, camera pixel density, laser power to mass ratio, et cetera will continue their exponential improvement. 03:33: The basic concept is the same-- an extremely low mass laser powered light sail. 07:00: It's assumed that processor size, camera pixel density, laser power to mass ratio, et cetera will continue their exponential improvement. 03:38: The main innovation of the Starshot is that it's not just low mass, it is ultra low mass, weighing in at grams rather than Starwisp's kilograms.
	2016-04-27: What Does Dark Energy Really Do? 04:04: When the star reaches a critical mass, a runaway fusion reaction obliterates the star as a supernova.
	2016-04-13: Will the Universe Expand Forever? 12:28: And it was blasted away by supernovae from the most massive stars it produced.
	2016-04-06: We Are Star Stuff 00:31: Space, time, energy, mass. 05:36: ... the largest stars, any bigger than around eight times the sun's mass, reach the ends of their lives, they become super giants, and their cores ... 08:47: ... a white dwarf, a remnant of a low mass star like the sun, has a binary partner star and manages to accrete, to ... 09:40: When they collide, most of their mass gets sucked into a newly born black hole. 09:45: ... newly formed heavy matter, including something like 10% of the Earth's mass in ... 05:36: ... the largest stars, any bigger than around eight times the sun's mass, reach the ends of their lives, they become super giants, and their cores ... 08:47: ... a white dwarf, a remnant of a low mass star like the sun, has a binary partner star and manages to accrete, to steal ... 09:27: ... two very massive stars in binary orbit leave behind neutron star corpses, those remnants ...
	2016-03-30: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners! 04:44: But let's use a number that's easy to find online, the baryonic mass of the universe, which is estimated at 10 to the power of 53 kilograms. 04:55: That's the mass of all the protons and neutrons in the observable universe. 05:11: ... divide the 10 to the 53 kilograms by the mass of the proton, and we get that there are 6 by 10 to the 79 protons in ... 05:28: 75% of the baryonic mass is in hydrogen, which has just one proton and no neutrons. 05:37: But our estimate of the total mass isn't accurate enough to bother factoring this in.
	2016-03-23: How Cosmic Inflation Flattened the Universe 11:52: ... example, in a reference frame of an unmoving center of mass, you have a center-pointing or centripetal force-- in this case, that's ...
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 02:23: ... the strength of gravity drops off with the distance to the center of mass squared, and it drops off at the same rate in all ... 08:29: These things are even more massive than single planets or stars. 11:12: Felix Ironfist asks, "why didn't the universe collapse into a black hole, if it was so dense and massive?" This is a classic question. 13:37: However, our scientific understanding of human psychology is massively helpful in understanding human motives and values. 08:29: These things are even more massive than single planets or stars. 11:12: Felix Ironfist asks, "why didn't the universe collapse into a black hole, if it was so dense and massive?" This is a classic question. 13:37: However, our scientific understanding of human psychology is massively helpful in understanding human motives and values.
	2016-03-09: Cosmic Microwave Background Challenge 03:24: ... need an estimate of the baryonic mass and volume of the observable universe, you'll need the redshift of the ...
	2016-03-02: What’s Wrong With the Big Bang Theory? 01:40: In a previous episode, we talked about how the Higgs field gives particles mass. 01:52: ... turns out that when you take this Higgs mass away from the particles that carry the weak nuclear force, they become ...
	2016-02-17: Planet X Discovered?? + Challenge Winners! 01:31: ... a single compelling solution, a very, very distant giant planet, with a mass well over 10 times that of the Earth, and a stretched out eccentric ... 02:03: Given its mass, the best guess is that it would also be a gas giant, something like Neptune or Uranus.
	2016-02-11: LIGO's First Detection of Gravitational Waves! 02:06: Now, LIGO is sensitive to pairs of stellar mass black holes and/or neutron stars. 07:47: Astronauts on the International Space Station lose bone mass at 1% to 1.5% per month, and lose muscle mass also. 02:06: Now, LIGO is sensitive to pairs of stellar mass black holes and/or neutron stars. 01:53: Any orbiting pair of massive objects generates gravitational waves. 01:57: ... only extremely massive objects, through orbiting extremely close together, produce ... 01:53: Any orbiting pair of massive objects generates gravitational waves. 01:57: ... only extremely massive objects, through orbiting extremely close together, produce ... 01:53: Any orbiting pair of massive objects generates gravitational waves. 01:57: ... only extremely massive objects, through orbiting extremely close together, produce gravitational waves ... 01:53: Any orbiting pair of massive objects generates gravitational waves.
	2016-02-03: Will Mars or Venus Kill You First? 01:13: Mass is only 1/10 the mass of the Earth, and 40% of its surface gravity. 05:21: But that low constant solar wind is nothing compared to a coronal mass ejection. 05:49: ... you can actually shield against a coronal mass ejection with around a 1 meter thickness of water or potentially food, ... 06:17: So we can know when one of these coronal mass ejections are coming and take cover. 08:15: I'm leaning towards the hashtag Occupy Venus movement, despite what masses 0.4 g would do for my basketball game. 05:21: But that low constant solar wind is nothing compared to a coronal mass ejection. 05:49: ... you can actually shield against a coronal mass ejection with around a 1 meter thickness of water or potentially food, human ... 06:17: So we can know when one of these coronal mass ejections are coming and take cover. 08:15: I'm leaning towards the hashtag Occupy Venus movement, despite what masses 0.4 g would do for my basketball game.
	2016-01-27: The Origin of Matter and Time 00:00: [MUSIC PLAYING] Einstein's theory of special relativity has shown us mass and time are not the concrete things we imagine them to be. 00:35: Maybe color, shape, size, mass. 00:55: A thing's mass, and a thing's experience of time. 08:50: ... this picture, time and mass and matter become emergent properties of the causal propagation of ... 09:26: ... flip, is experiencing time, which goes hand-in-hand with them having mass. ... 09:38: However, quarks and electrons gain their intrinsic mass by interacting with the Higgs field. 06:17: ... already covered the fact that real matter is comprised of massless light speed components confined not by mirrored walls, but by ... 06:28: ... the atom, in which the familiar electrons and quarks are composites of massless particles confined by the Higgs ... 08:50: ... of the causal propagation of patterns of interactions between timeless, massless ... 09:48: The familiar electron is really a composite of the left and the right-handed chirality electron and anti-positron, which on their own are massless. 06:17: ... already covered the fact that real matter is comprised of massless light speed components confined not by mirrored walls, but by interactions ... 06:28: ... the atom, in which the familiar electrons and quarks are composites of massless particles confined by the Higgs ... 08:50: ... of the causal propagation of patterns of interactions between timeless, massless parts. ...
	2016-01-13: When Time Breaks Down 00:02: In the last episode, we saw how matter fills mass because of the energy of its internal moving parts. 02:34: ... turn will show us why light speed particles are timeless, and why having mass and experiencing time are fundamentally ... 02:46: ... which despite being composed only of massless things, itself does have mass. ... 06:00: Note that this is not the same thing as accelerating the photon box, which gives it the feeling of mass. 07:14: So the confinement of light speed particles gives matter mass. 07:55: In the last episode, we talked about the true nature of matter and mass. 08:13: However, the thought experiment still works if you say that the walls do have some mass. 08:18: In that case, the box's mass increases by the amount equal to the energy of the contained photons, divided by the speed of light squared. 08:35: And yes, it really is more massive, but not by much. 09:17: So it feels massive, regardless of the direction in which you push it. 08:35: And yes, it really is more massive, but not by much. 09:17: So it feels massive, regardless of the direction in which you push it. 02:46: ... of atoms-- protons and neutrons-- to the imaginary photon box, a massless mirrored box filled with light, which despite being composed only of ... 08:02: Paramdeep Singh, and a few others, questioned the plausibility of massless walls in our photon box thought experiment. 08:10: And yes, massless walls are impossible. 02:46: ... of atoms-- protons and neutrons-- to the imaginary photon box, a massless mirrored box filled with light, which despite being composed only of massless ... 08:02: Paramdeep Singh, and a few others, questioned the plausibility of massless walls in our photon box thought experiment. 08:10: And yes, massless walls are impossible.
	2016-01-06: The True Nature of Matter and Mass 00:02: NARRATOR: Einstein showed us that matter, mass, and the flow of time are intrinsically connected, but opened the question, are they even real? 00:32: Anything without mass has to travel this speed. 00:36: But what is it about mass that prevents something from reaching the ultimate speed? 00:49: So today, we're going to look at the true nature of matter and mass a little more closely. 00:54: ... famous equation, E equals Mc squared, and showed that most of the mass of atoms comes from the kinetic and binding energy of the quarks that ... 01:05: But saying that mass is energy doesn't really get us very far. 01:14: For now, let's look at this energy in terms of what's actually happening in an object when it exerts this property we call mass. 01:22: Let's ignore the gravitational effect of mass for the moment, and just consider mass as the degree to which an object resists being accelerated. 01:31: We call this inertial mass. 02:45: Acceleration is resisted in a way that feels exactly like mass. 02:50: In fact, it's indistinguishable from mass, because it is mass. 02:54: The photon box is massive, even though none of its components-- not the photons, not the walls-- have any mass. 03:02: Somehow, mass arises in the ensemble where it doesn't exist in the parts. 03:07: How much mass does the box have? 03:23: But E equals Mc squared describes the universal relationship between mass and confined energy, not just confined photons. 04:16: ... and the compressed spring-- both give the same translation between mass and energy, E equals Mc squared, because the underlying cause is the ... 04:55: 99% of the mass of the proton is in the vibrational energy of the quarks plus the binding energy of the gluon field. 05:03: The actual intrinsic mass of the quarks is a tiny contribution. 05:22: And as we saw recently, even those quarks, as well as electrons, gain their tiny masses from a type of confinement via the Higgs field. 05:36: ... looks like everything with mass is composed of a combination of intrinsically massless, light-speed ... 05:49: So is mass really not a fundamental property? 06:01: This acceleration resisting mass, inertial mass, seems to be an emergent property of the ensemble. 06:08: But we can't talk about mass without talking about gravity. 06:15: They have what we call gravitational mass. 06:17: But how does the inertial mass of our photon box end up translating to gravitational mass? 07:04: In fact, the equivalence principle tells us that the gravitational mass of an object and the inertial mass are the same thing. 07:11: But mass doesn't just respond to a gravitational field. 07:16: Mass curves the fabric of space. 07:19: Actually, it turns out that it's not just mass that bends space. 07:44: OK, so mass is an emergent property of the interactions of massless particles. 07:57: But our photon box has mass, so it must experience time. 08:18: ... Time," we talked about how the Higgs field gives elementary particles mass. ... 09:37: It's really the composite particle that has mass. 10:25: Then the weak force carriers gained mass and became differentiated from the electromagnetic carrier-- the photon. 03:02: Somehow, mass arises in the ensemble where it doesn't exist in the parts. 07:16: Mass curves the fabric of space. 07:11: But mass doesn't just respond to a gravitational field. 06:01: This acceleration resisting mass, inertial mass, seems to be an emergent property of the ensemble. 05:22: And as we saw recently, even those quarks, as well as electrons, gain their tiny masses from a type of confinement via the Higgs field. 02:54: The photon box is massive, even though none of its components-- not the photons, not the walls-- have any mass. 03:40: So is a compressed spring more massive than a relaxed one? 04:13: It feels like it's more massive, because it is. 06:11: Massive objects exert and respond to the force of gravity. 02:54: The photon box is massive, even though none of its components-- not the photons, not the walls-- have any mass. 03:40: So is a compressed spring more massive than a relaxed one? 04:13: It feels like it's more massive, because it is. 06:11: Massive objects exert and respond to the force of gravity. 01:38: Imagine a massless box with mirrored walls-- impossible, I know, but it's an analogy for something real, as we'll see. 01:45: Now fill it with photons, also massless, that bounce around inside the box in all directions. 05:31: Take away the Higgs field, and they are massless speed of light particles. 05:36: ... like everything with mass is composed of a combination of intrinsically massless, light-speed particles that are prevented from streaming freely through ... 05:52: Is it just the result of massless particles and fields bumping and sloshing around inside things resisting acceleration? 07:39: So confined massless particles generate a very real gravitational field. 07:44: OK, so mass is an emergent property of the interactions of massless particles. 07:51: A single photon experiences no time, nor does any massless particle. 09:06: Felix Feist points out that given that the right-handed electron doesn't have weak hypercharge, shouldn't it be massless? 09:40: The naked left- or right-handed electron is massless. 01:38: Imagine a massless box with mirrored walls-- impossible, I know, but it's an analogy for something real, as we'll see. 05:36: ... like everything with mass is composed of a combination of intrinsically massless, light-speed particles that are prevented from streaming freely through the universe, ... 07:51: A single photon experiences no time, nor does any massless particle. 05:52: Is it just the result of massless particles and fields bumping and sloshing around inside things resisting acceleration? 07:39: So confined massless particles generate a very real gravitational field. 07:44: OK, so mass is an emergent property of the interactions of massless particles. 07:39: So confined massless particles generate a very real gravitational field. 05:31: Take away the Higgs field, and they are massless speed of light particles.
	2015-12-16: The Higgs Mechanism Explained 00:14: ... PLAYING] We saw in a previous episode that most of the mass in your body, in fact, the mass of anything that's made of atoms, ... 00:28: The electrons, and the quarks that comprise protons and neutrons, do seem to have intrinsic mass, but this is only run 1% of the mass of the atom. 00:36: Most of the atom's mass is the confined kinetic and binding energy of those quarks. 00:41: Now, today I want to talk about this so-called intrinsic mass of the elementary particles. 00:47: I want to show you that even in this case, mass is still just bound or confined energy. 02:02: ... of the electron, and yes predicted that the electron should have no mass. ... 02:51: The electron evolves, meaning it does experience time, so it must have mass. 02:58: We've measured that mass directly. 03:00: ... of changeability is the only way that we know that the tiny neutrino has mass, and it was the measurement of those neutrino oscillations the won the ... 03:30: But the photon and the electron are both just excitations in their own fields, so why does the electron have mass and the photon not? 05:44: On its own, the electron would travel at light speed, but trapped in this Higgs field buzz, the electron feels mass. 06:32: This particle actually has nothing to do with giving anything mass. 08:06: ... grow because anything falling into the black hole adds to its effective mass as seen by a distant observer even before it crosses the event ... 08:29: The Schwarzschild radius is the radius of the event horizon of a non-rotating black, and it depends on the mass. 02:58: We've measured that mass directly. 06:11: We conclude that QFT is essentially correct, but it's an incomplete theory without a mass-giving field. 09:05: ... stars near the core of a galaxy with merging super massive black holes should have temperatures raised by an observable amount by ... 02:14: The basic QFT equations of all the components of the atom leave them massless. 02:19: As we'll see in the next couple of episodes, this masslessness means that particles should travel only at the speed of light and experience no time. 03:13: It is definitely massless. 02:19: As we'll see in the next couple of episodes, this masslessness means that particles should travel only at the speed of light and experience no time.
	2015-12-09: How to Build a Black Hole 00:56: Yet, to actually form a black hole, Einstein's descriptions of mass energy and space time are not enough. 02:17: ... is a very weird beast-- a bowl of neutrons the size of a city, with a mass of at least 1.4 suns and the density of an atomic ... 08:12: However, if we can increase the mass of the neutron star, the actual star shrinks, and the event horizon expands. 08:22: There's a mass where the radius of the neutron star and the event horizon overlap. 08:26: It's three times the mass of the sun. 10:16: The mass of the stellar core becomes the apparent mass of the black hole. 10:24: The black hole retains mass, electric charge, and spin. 12:35: ... if we want a ring system like Sam's, that has the same ratio of planet mass to ring mass-- of about 1 to 50 billion, then we'd need an object the ... 10:24: The black hole retains mass, electric charge, and spin. 00:56: Yet, to actually form a black hole, Einstein's descriptions of mass energy and space time are not enough. 01:09: First step-- find a very massive star, and wait. 01:27: The details of the deaths of massive stars are pretty awesome. 01:33: ... the last throes of a very massive star's life, increasingly frantic fusion in the interior produces one ... 01:09: First step-- find a very massive star, and wait. 01:27: The details of the deaths of massive stars are pretty awesome. 01:33: ... the last throes of a very massive star's life, increasingly frantic fusion in the interior produces one ... 01:09: First step-- find a very massive star, and wait. 01:27: The details of the deaths of massive stars are pretty awesome. 01:33: ... the last throes of a very massive star's life, increasingly frantic fusion in the interior produces one periodic ...
	2015-11-25: 100 Years of Relativity + Challenge Winners! 02:13: ... some Newtonian mechanics to see how much mass is needed to accelerate Apophis to get the desired change in position ... 03:06: How much mass do we need to provide the necessary acceleration? 03:10: Well, we know that the spacecraft's mass is changing because it needs to burn fuel to accelerate. 03:16: But we can just calculate the average acceleration based on the average mass of the spacecraft plus fuel over the seven years. 03:24: ... to determine the acceleration at every point based on the changing mass. ... 03:34: So the mass that we're going to calculate is the average mass of the spacecraft in fuel over the seven years. 04:03: What mass is needed to produce this acceleration? 04:06: Our spacecraft is hovering 325 meters from the center of mass of Apophis. 04:18: It also gives us the acceleration experienced by Apophis due to the mass of the spacecraft and the fuel. 04:24: Note that Apophis' mass cancels out, but don't worry. 04:43: So the average mass needed to achieve the acceleration we calculated earlier comes to 1,600 metric tons. 04:51: This is around 80% of the mass of the space shuttle so we can definitely do this. 05:01: ... of the fuel and the ratio of fueled to unfueled or wet to dry spacecraft mass. ... 05:14: But what are these masses? 05:16: We're trying to pull the entire asteroid, so we have to include its mass as part of the spacecraft mass. 05:23: But the mass of Apophis is enormous compared to the spacecraft-- 30 billion kilograms compared to the 1.6 million kilograms we got earlier. 05:33: So the dry mass may as well just be Apophis' mass. 05:36: The wet mass is then just Apophis' mass plus the fuel mess. 05:40: Rearranging all of this, we get this equation for the ratio of fuel mass to asteroid mass. 06:34: Putting this together, we get a ratio of fuel mass to asteroid mass of 5.3 by 10 to the minus 7. 06:41: So the fuel mass we need is around 16 metric tons, which is great because that's only 1% of the spacecraft mass. 07:11: ... of our pulsed future drive and so we need almost as much initial fuel mass as spacecraft ... 04:24: Note that Apophis' mass cancels out, but don't worry. 04:43: So the average mass needed to achieve the acceleration we calculated earlier comes to 1,600 metric tons. 05:14: But what are these masses? 04:12: Newton's law of universal gravitation tells us the force between two massive objects.
	2015-11-18: 5 Ways to Stop a Killer Asteroid 05:17: Now unfortunately, this doesn't work for planet killers, which are at least a million times more massive.
	2015-11-11: Challenge: Can you save Earth from a Killer Asteroid? 01:54: ... exhaust velocity and the ratio of wet to dry, or fueled to unfueled, mass. ... 02:05: ... propellant use over the seven years and calculate an average spacecraft mass. ... 01:38: How massive would the spacecraft, including the fuel, need to be?
	2015-11-05: Why Haven't We Found Alien Life? 10:55: ... traverse the walls in any direction besides forwards and our negative mass matter may also end up on the ... 01:41: And as if it wasn't hard enough to do statistics with a sample size of one, we also have to deal with a massive selection bias.
	2015-10-28: Is The Alcubierre Warp Drive Possible? 01:27: That limit, the speed of light, refers to things-- mass, energy, information-- traveling through space. 02:12: Basically, mass and energy tell us how space should warp. 03:49: ... on macroscopic scales, you'd probably need some sort of exotic negative mass matter, like element zero, which is tricky, because there may be no such ... 04:37: ... that you can even make negative mass matter, to make a warp field, some of it would need to go outside the ... 05:16: Later refinements brought this down to the mass equivalent of Jupiter. 05:43: And this brings mass needed down to kilograms. 05:46: ... style, which could get us down to needing only milligrams of negative mass. ... 01:27: That limit, the speed of light, refers to things-- mass, energy, information-- traveling through space. 05:16: Later refinements brought this down to the mass equivalent of Jupiter. 03:49: ... on macroscopic scales, you'd probably need some sort of exotic negative mass matter, like element zero, which is tricky, because there may be no such ... 04:37: ... that you can even make negative mass matter, to make a warp field, some of it would need to go outside the warp ... 05:43: And this brings mass needed down to kilograms. 02:16: But if you're cheeky, you can actually just make up a solution to the equations of GR without starting with a real mass/energy distribution. 03:19: There's just no guarantee that the resulting mass/energy distribution would be physically meaningful. 05:08: In fact, it would take significantly more negative energy than there is positive mass/energy in the entire observable universe. 05:25: Thicken the walls of the warp field, and you get the negative mass/energy requirement down to the equivalent of maybe the moon or even an asteroid. 02:16: But if you're cheeky, you can actually just make up a solution to the equations of GR without starting with a real mass/energy distribution. 03:19: There's just no guarantee that the resulting mass/energy distribution would be physically meaningful. 05:08: In fact, it would take significantly more negative energy than there is positive mass/energy in the entire observable universe. 05:25: Thicken the walls of the warp field, and you get the negative mass/energy requirement down to the equivalent of maybe the moon or even an asteroid. 02:16: But if you're cheeky, you can actually just make up a solution to the equations of GR without starting with a real mass/energy distribution. 03:19: There's just no guarantee that the resulting mass/energy distribution would be physically meaningful. 05:25: Thicken the walls of the warp field, and you get the negative mass/energy requirement down to the equivalent of maybe the moon or even an asteroid.
	2015-10-22: Have Gravitational Waves Been Discovered?!? 00:29: Instead, mass warps the fabric of 4-D spacetime, leading to what we see as gravitational motion. 00:48: There's the dragging of spacetime by spinning masses. 01:39: ... a mass through space in the right way, and you produce gravitational ripples-- ... 01:51: Here's a technical term-- you need to change the quadrupole moment of a mass distribution. 00:29: Instead, mass warps the fabric of 4-D spacetime, leading to what we see as gravitational motion. 00:48: There's the dragging of spacetime by spinning masses. 04:22: ... so when, say, two massive objects orbit each other close enough to produce a lot of this ... 02:42: And all massless things, including g-waves and light, must travel at that speed.
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 02:18: The rocket equation tells us that maximum speed is based on exhaust velocity, fuel mass, and spacecraft mass. 02:38: But there are two ways to achieve high velocities, propel a lot of mass backwards or propel less mass at much higher speeds. 02:51: So direct conversion of rest mass into energy seems like the way to go. 03:16: ... thermonuclear devices and launch with roughly 3/4 of our starship's mass being taken up by 300,000 1 megaton hydrogen bombs, blast them behind us ... 04:40: But fusion turns less than 1% of rest mass into energy. 04:50: When matter meets it's antimatter counterpart, both particles are annihilated, liberating most of the rest mass as energy. 07:52: This is a black hole made not from mass but from light. 02:38: But there are two ways to achieve high velocities, propel a lot of mass backwards or propel less mass at much higher speeds. 06:55: ... have to be ridiculously large, possibly built on the moon and powered by massive Helium 3 reactors or in orbit around the sun powered by vast solar ... 08:38: Larger and it radiates too weakly and becomes too massive to feasibly accelerate the ship and the black hole. 06:55: ... have to be ridiculously large, possibly built on the moon and powered by massive Helium 3 reactors or in orbit around the sun powered by vast solar ... 08:38: Larger and it radiates too weakly and becomes too massive to feasibly accelerate the ship and the black hole. 06:55: ... have to be ridiculously large, possibly built on the moon and powered by massive Helium 3 reactors or in orbit around the sun powered by vast solar ...
	2015-10-07: The Speed of Light is NOT About Light 08:57: So lights or photons, also gravitational waves and gluons all have no mass. 09:05: Mass is an impediment to motion. 09:07: No mass, no impediment. 09:12: In fact, the very existence of mass and space and time tells us that the universal speed limit is finite. 09:19: ... of relativity-- time dilation, length contraction, and, of course, mass to energy equivalence, as described by the famous equation, E equals mc ... 09:53: Because it would take infinite energy to make any mass. 06:17: Position, orientation, and velocity are changing massively. 08:53: Because of this, it's the only speed that any massless particle can travel. 09:09: So massless things go as fast as it's possible to go. 09:56: There is only massless particles traveling at infinite speed. 08:53: Because of this, it's the only speed that any massless particle can travel. 09:56: There is only massless particles traveling at infinite speed. 09:09: So massless things go as fast as it's possible to go.
	2015-09-30: What Happens At The Edge Of The Universe? 04:22: But for now, let's just assume we have a nice Alcubierre-class warp-ship and we burn the mass energy of entire stars to chase the particle horizon. 08:03: For example, the predictions GR makes for planetary orbits can give us a mass for the Sun. 08:09: And that mass predicts the deflection angle for light passing the Sun perfectly, that is its gravitational lensing effect. 08:18: The galaxy orbits give us a mass for the dark matter in the clusters and the lensing gives us a mass consistent with this. 04:22: But for now, let's just assume we have a nice Alcubierre-class warp-ship and we burn the mass energy of entire stars to chase the particle horizon. 08:09: And that mass predicts the deflection angle for light passing the Sun perfectly, that is its gravitational lensing effect.
	2015-09-23: Does Dark Matter BREAK Physics? 00:24: ... calculate from everything we can see, we can only account for 10% of the mass needed to hold its stars in ... 01:16: From this, we can figure out exactly how much mass is needed to cause the observed lensing. 01:22: But again, we find the clusters appear to have way more mass than we see in the stars alone, that is if we understand gravity. 01:48: Or three, even worse, we're actually not missing any mass. 02:12: If dark matter exists in this model, its mass probably needs to come from protons and neutrons. 03:10: Either particle physics is wrong, or at least horribly incomplete, in that we're missing 80% to 90% of the mass in the universe, or Einstein is wrong. 04:58: In the Bullet Cluster, most of the mass actually is in the gas. 05:21: Map the mass based on the warping of light from more distant galaxies. 00:24: ... calculate from everything we can see, we can only account for 10% of the mass needed to hold its stars in ... 02:19: ... matter, the galaxy would need to be swarming with baryonic things as massive as stars, but that are so compacted that they're basically ... 02:34: They're called MACHOs, massive compact halo objects. 06:23: And even then, galaxies could only have formed if dark matter particles are cold, massive, and weakly interacting. 06:30: Weakly interacting massive particles, WIMPs, actually refers to a specific and popular contender for dark matter. 06:46: ... familiar standard model particles, but that are hundreds of times more massive. ... 02:19: ... matter, the galaxy would need to be swarming with baryonic things as massive as stars, but that are so compacted that they're basically ... 02:34: They're called MACHOs, massive compact halo objects. 06:23: And even then, galaxies could only have formed if dark matter particles are cold, massive, and weakly interacting. 06:30: Weakly interacting massive particles, WIMPs, actually refers to a specific and popular contender for dark matter. 06:46: ... familiar standard model particles, but that are hundreds of times more massive. ... 02:34: They're called MACHOs, massive compact halo objects. 06:30: Weakly interacting massive particles, WIMPs, actually refers to a specific and popular contender for dark matter.
	2015-08-19: Do Events Inside Black Holes Happen? 05:27: In that respect, the black hole certainly behaves like an object, an object with the Sun's mass. 05:32: So we associate one solar mass with the black hole itself. 05:36: ... fact, if I give you a spherical object of any mass M, a spherical black hole with this special radius, called the ... 05:52: One with the mass of Earth would have a radius of just under 1 centimeter. 05:58: So is that collection of events somehow mimicking mass or does it actually have mass? 08:37: ... on what you mean by "density." If you know that it's the black hole mass divided by the volume inside the horizon, then ... 08:50: For instance, the 4 million solar mass black hole at the center of the Milky Way is about as dense as water. 09:05: ... even though a solar mass black hole would spaghettify you from pretty far away, you could enter a ... 09:27: Misconception number three actually brings us full circle back to the mass question that I raised earlier. 09:42: In this situation, the mass of the precursor star and the associated mass of the black hole will indeed be the same. 09:58: So in this scenario, we can kind of sidestep the whole mass issue. 10:18: ... and I've always felt that whatever we're going to say a black hole's mass is the mass of, it should apply equally well to astrophysical black ... 10:30: And in this circumstance, what are we supposed to assign the black hole's mass to? 10:37: So is the mass a property of the singularity? 10:52: So where's the mass? 08:50: For instance, the 4 million solar mass black hole at the center of the Milky Way is about as dense as water. 09:05: ... even though a solar mass black hole would spaghettify you from pretty far away, you could enter a ... 08:50: For instance, the 4 million solar mass black hole at the center of the Milky Way is about as dense as water. 09:05: ... even though a solar mass black hole would spaghettify you from pretty far away, you could enter a billion ... 08:37: ... on what you mean by "density." If you know that it's the black hole mass divided by the volume inside the horizon, then ... 09:58: So in this scenario, we can kind of sidestep the whole mass issue. 09:27: Misconception number three actually brings us full circle back to the mass question that I raised earlier. 08:47: More massive black holes can have very low density. 09:33: ... a black hole can form when a sufficiently massive object, typically a very heavy star, collapses and becomes more compact ... 08:47: More massive black holes can have very low density. 09:33: ... a black hole can form when a sufficiently massive object, typically a very heavy star, collapses and becomes more compact ... 08:47: More massive black holes can have very low density. 09:33: ... a black hole can form when a sufficiently massive object, typically a very heavy star, collapses and becomes more compact than its ...
	2015-08-12: Challenge: Which Particle Wins This Race? 00:22: ... and time are two separate things, and gravity is an actual force that masses exert on each ... 00:32: Pretend you have a sphere with the same mass density throughout. 00:59: ... out an expression for the orbital speed of this particle in terms of the mass and radius of the planet, or in terms of the density and radius of the ... 02:01: After all, as it falls, some of the mass is above it. 02:15: ... the particle will feel only the gravitational force from whatever mass is closer to the center of the planet than the particle ... 03:04: The answer to which particle wins the race comes out the same regardless of the mass and radius of the planet, or of the masses of the two particles. 00:32: Pretend you have a sphere with the same mass density throughout. 00:22: ... and time are two separate things, and gravity is an actual force that masses exert on each ... 03:04: The answer to which particle wins the race comes out the same regardless of the mass and radius of the planet, or of the masses of the two particles. 00:22: ... and time are two separate things, and gravity is an actual force that masses exert on each ... 00:40: For simplicity, I'm going to refer to this sphere as a planet, but it could be any other massive body.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 03:31: ... all objects accelerate off the surface identically, regardless of their mass. ... 04:05: Remember, the object's mass doesn't matter. 07:31: The Sun is more massive, yes, but it's also much further away.
	2015-06-17: How to Signal Aliens 04:30: Now, these objects wouldn't need to be the same mass as a planet. 02:03: ... distances with microwave transmission are possible, it would require a massive ongoing investment of humanities resources to go loud enough and last ...
	2015-06-03: Is Gravity An Illusion? 01:57: ... other words, the net force on an object will equal that object's mass times its acceleration only if you're measuring that acceleration using ...
	2015-05-27: Habitable Exoplanets Debunked! 03:00: ... years from Earth, Kepler 186F is just too far away to determine its mass or anything about its atmosphere with current or planned ... 03:15: You can put limits on its mass by considering extremes of what it could be made out of. 04:12: ... you combine that information with the planet's mass, radius, and distance from its star, you can use models to get a rough ... 06:50: If everyone on Earth picked up a hammer at the same time, by how much would Earth's mass increase due to the excess gravitational potential energy? 06:59: Earth's mass would stay exactly the same. 07:01: ... ATP in your muscles and thus was already being weighed as part of the mass of the ... 07:17: Energy would have been injected into the system, and Earth's mass would negligibly increase. 08:02: Hansen from It's OK To Be Smart asked, if my mirrored box had a tiny hole in it so some light could escape, would its mass go down? 08:17: Dan Cattell asked whether the human body really does lose a little bit of mass when it dies. 08:26: ... alone would mean there's less thermal energy contributing to the total mass. ... 08:41: ... energy than it did before, then that configuration will have less mass, and the x's potential energy would had to have been released in some ... 09:04: Natalia B, Pablo Herrero, and Gorro Rojo all asked whether photons actually have mass if they have energy. 09:17: Also check out an excellent video MinutePhysics titled, "What Is Mass," and I think it'll give you some clarity about the question. 09:56: ... in the SI system of units, amount of stuff, the SI unit of the mole, and mass, the SI kilogram, are defined in terms of one ... 10:17: ... the kilogram would be redefined as the total amount of effective mass you'd have from putting some number of photons in a mirrored box, more ... 10:26: ... will reflect the physics that I articulated in this episode, namely that mass and amount of stuff are independent ... 06:50: If everyone on Earth picked up a hammer at the same time, by how much would Earth's mass increase due to the excess gravitational potential energy? 04:12: ... you combine that information with the planet's mass, radius, and distance from its star, you can use models to get a rough picture of ...
	2015-05-20: The Real Meaning of E=mc² 00:02: A hydrogen atom has less mass than the combined masses of the proton and the electron that make it up. 00:33: That's because at its core, this cornerstone of physics is really a lesson in how to think about what mass is. 00:39: You'll often see statements like "mass is a form of energy" or "mass is frozen energy" or "mass can be converted to energy." That's the worst one. 00:51: ... things that it implies that seem at odds with our everyday experience of mass. ... 01:01: Even if two objects are made up of identical constituents, those objects will not in general have equal masses. 01:08: The mass of something that's made out of smaller parts is not just the sum of the masses of those parts. 01:14: ... the total mass of the composite object also depends on, one, how it's parts are ... 01:33: According to Einstein, the watch that's running has a greater mass. 01:59: ... resides in the watch's parts manifests itself as part of the watch's mass. ... 02:11: ... divide it by the speed of light squared, and that's how much extra mass the kinetic and potential and thermal energies of the parts contribute ... 02:20: Now since the speed of light is so huge, this extra mass is tiny, only about a billionth of a billionth of a percent of the total mass of the watch. 02:28: That's why, according to Einstein, most of us have always incorrectly believed that mass is an indicator of the amount of matter in an object. 02:44: Am I saying that individually, the mass of the minute hand is bigger because the minute hand is moving? 02:51: Most contemporary physicists mean mass while at rest, or "rest mass," when they talk about mass. 02:56: In modern parlance, the phrase "rest mass" is redundant. 02:59: ... are lots of good reasons for talking this way, among them that rest mass is a property all observers agree about, much like the space-time ... 03:12: For us, today, the m in m equals E over c squared is rest mass. 03:37: ... the battery, and thus manifesting as part of the flashlight's total mass. ... 03:48: ... yes, since the sun is basically an enormous flashlight, its mass drops just by virtue of the fact that it shines by about 4 billion ... 03:59: That's just a billionth of a trillionth of the sun's mass, and only 0.07% of the sun's mass over its entire 10 billion year lifespan. 04:06: So does this mean that the sun converts mass to energy? 04:17: ... contained within the volume of the sun manifesting as part of the sun's mass. ... 04:49: The flashlight alone will lose mass, but the mass of the whole box and its contents will stay fixed. 05:03: ... if you confine it in a box, its energy still contributes to the total mass of that box via m equals E over c ... 05:21: ... at the top of the episode, I stated that the mass of a hydrogen atom is less than the combined masses of the electron and ... 05:58: ... comes out negative, and a hydrogen atom weighs less than the combined masses of its ... 06:12: ... all atoms on the periodic table weigh less than the combined masses of the protons, neutrons, and electrons that make them ... 06:33: They're made of particles called quarks, whose combine mass is about 2,000 to 3,000 times smaller than a proton's or neutron's mass. 06:39: So where does the proton's mass come from? 06:54: All right, what about the masses of electrons and quarks? 06:57: At least in the standard model of particle physics, they're not made up of smaller parts, so where does their mass come from? 07:02: Is it some kind of baseline mass in the pre-Einstein sense of the word? 07:05: Well, that's a subtle question, but crudely speaking, you can think even of this mass as being a reflection of various kinds of potential energies. 07:29: Doesn't that have to be thought of as mass being converted into energy? 07:40: You never need mass to energy alchemy. 07:43: But please take my word for it, you don't actually have to talk about converting mass to energy ever. 07:49: Instead, the punchline of this episode has been that mass isn't really anything at all. 07:58: ... in that sense, even though it's not correct to think of mass is an indicator of amount of stuff in the material sense, you can think ... 08:35: ... the first because the second block is higher up, so it will have more mass than the ... 08:51: Would the total mass of the planet increase, and if so by how much? 03:48: ... yes, since the sun is basically an enormous flashlight, its mass drops just by virtue of the fact that it shines by about 4 billion kilograms ... 07:49: Instead, the punchline of this episode has been that mass isn't really anything at all. 00:02: A hydrogen atom has less mass than the combined masses of the proton and the electron that make it up. 01:01: Even if two objects are made up of identical constituents, those objects will not in general have equal masses. 01:08: The mass of something that's made out of smaller parts is not just the sum of the masses of those parts. 05:21: ... I stated that the mass of a hydrogen atom is less than the combined masses of the electron and the proton that make it ... 05:58: ... comes out negative, and a hydrogen atom weighs less than the combined masses of its ... 06:12: ... all atoms on the periodic table weigh less than the combined masses of the protons, neutrons, and electrons that make them ... 06:54: All right, what about the masses of electrons and quarks? 05:03: ... right, even though light itself is massless, if you confine it in a box, its energy still contributes to the total ...
	2015-05-13: 9 NASA Technologies Shaping YOUR Future 07:33: First, Sengo said maybe all men would require less radiation shielding, which would also reduce massing costs of the trip.
	2015-05-06: Should the First Mars Mission Be All Women? 03:55: While you can recycle air and water, you need to take all the food mass with you on a trip to Mars. 04:02: ... women need less food to do the same activity as men, so that means less mass to transport, less propellant, and thus lower ... 05:09: So how much food mass could you save if you used all women? 05:22: ... half the crew-- you can knock out about a third of your total food mass. ... 05:33: So how does that mass savings translate into dollar savings? 06:17: ... food plus food fuel would thus represent around 5% to 7% of the mission mass and 5% to 7% of the launch cost, which might be 0.5% to 1% of the ... 08:25: ... is done apparently in "Mass Effect," the "Expanse" series, another Niven work called "The Mote in ... 05:33: So how does that mass savings translate into dollar savings?
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 01:06: You'd need either enormous amounts of mass, so much that you'd basically have a planet and not a starship. 01:10: Or you need something exotic, like gravitationally repulsive negative mass, which doesn't exist. 06:58: ... also estimated that each halo has as much mass as the entire asteroid belt. So new question, do any sci-fi franchises ...
	2015-04-15: Could NASA Start the Zombie Apocalypse? 05:00: The effects when you're releasing that little mass are basically additive. 05:18: At that point, the total amount of gas that you would have released would have been a non-trivial fraction of your body mass. 05:23: ... to compute everything correctly, you would have had to take that loss of mass into account and use a more correct version of momentum conservation ...
	2015-04-09: How to Weigh a Fart 00:20: ... which it probably does to a decent approximation, you could work out the mass of the fart once you know the average molecular mass of a fart ... 00:56: 1 gram worth of fart mass over a 24 hour period. 01:00: ... the same period, you would get somewhere between 0.05 and 0.1 grams of mass per ...
	2015-04-08: Could You Fart Your Way to the Moon? 02:03: So long as you throw enough mass sufficiently fast, it doesn't really matter what you're throwing. 03:22: Estimating the mass is more involved. 03:51: There's simply not enough mass in your gas. 04:14: And in case you're wondering, sneezing would probably have a similar result. The masses and exit speeds of sneezes and farts should be comparable. 04:46: ... per liter, the half liter or so capacity of a full bladder would have a mass of about half a ... 06:23: The Cosmos asked whether gravitational forces are about the mass or density of the gravitational source. 06:28: Answer-- once you're outside the gravitating object, what matters is mass. 04:14: And in case you're wondering, sneezing would probably have a similar result. The masses and exit speeds of sneezes and farts should be comparable.
	2015-04-01: Is the Moon in Majora’s Mask a Black Hole? 02:00: The same would be true on Termina, no matter what non-absurd radius and mass we assign to that planet. 05:08: ... estimates say that you'd still need at least 1/10 of the sun's mass, give or take, to make ... 05:39: ... you could somehow put a much denser mass at the center, the material around it might have enough of a ... 05:58: OK, what about condensing some of the necessary mass into a black hole? 06:17: It would lose mass and size during the process. 06:20: And about a gazillion years later, poof-- moon-ish mass, submillimeter-size black hole. 05:23: ... that's a quadrillion times more massive than MatPat's estimate, but still millions of times less than what you'd ... 06:13: You could start with a more massive and larger black hole and just let it evaporate slowly. 05:23: ... that's a quadrillion times more massive than MatPat's estimate, but still millions of times less than what you'd ... 06:13: You could start with a more massive and larger black hole and just let it evaporate slowly.
	2015-03-25: Cosmic Microwave Background Explained 06:37: A few of you asked, wouldn't the extra mass of the gyroscopes weigh just as much as extra mass from fuel? 06:43: ... fast, you could store up a lot of angular momentum with very little mass. ...
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 05:19: If you want to feel this physics in action, just get a bike wheel with some pegs, clamps to add mass, a spinning chair, and a couple of friends. 05:29: I don't have any numbers on the mass and rotational inertia of a "Star Fox" Arwing. 05:33: ... I can't tell you how massive or dense the gyros would need to be, whether you'd flip them mechanics ... 05:50: ... assuming you can spin a massive enough flywheel fast enough, without it breaking apart, and assuming the ... 09:05: But even if Ceres is an asteroid, it's only about three and a half times as massive as 4 Vesta, still not enough energy to destroy the Earth. 05:33: ... I can't tell you how massive or dense the gyros would need to be, whether you'd flip them mechanics ... 05:50: ... assuming you can spin a massive enough flywheel fast enough, without it breaking apart, and assuming the ... 09:05: But even if Ceres is an asteroid, it's only about three and a half times as massive as 4 Vesta, still not enough energy to destroy the Earth.
	2015-03-11: What Will Destroy Planet Earth? 00:24: Now in the case of Earth, the main glue is the collective gravity of almost six septillion kilograms of mass. 02:27: Now with those speeds, an object could only carry enough energy to destroy Earth if it had a huge mass, which asteroids don't. 04:27: In the process, the sun will lose a lot of mass and a lot of gravitational pull, causing Earth's orbit to actually grow.
	2015-03-04: Should We Colonize Venus Instead of Mars? 02:15: In Earth orbit, astronauts lose bone mass at about 10 times the rate of someone with advanced osteoporosis.
	2015-02-11: What Planet Is Super Mario World? 00:48: Now mass and shape are irrelevant. 04:19: Well, g on a given planet is determined by a combination of that planet's mass and its radius. 04:24: You can compute it with the following formula, using Earth's mass and radius as a reference. 04:52: ... are trickier, because astronomers don't have good estimates of both mass and radius for most ...

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