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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 00:03: ... we think of an exotic state of matter we tend to think of the really weird things that matter can do in ... 00:20: But there’s one state of matter that’s not solid, liquid or gas, but is also not confined to extreme or rare environments. 00:27: ... and you’ve often been the beneficiary of the powers of this state of matter without even knowing ... 00:43: I’m sure you know how states of matter work. 00:54: If you watched our episode on states of matter you’ll know it’s a bit more complicated than this. 01:00: For example, it’s not just temperature that determines the state of matter, it's also pressure. 01:35: Now, maps tend to be covered by nation states or states of the union, but this map has states of matter. 02:55: And beyond it is an entirely new state of matter - the here-be-dragons of the phase diagram. 03:11: In that region, matter becomes a sort of hybrid between liquid and gas called a supercritical fluid, sharing properties of both. 03:19: But this is a genuine, unique state of matter that can do things possible for neither liquid nor gases. 12:52: But Nature knew about this state of matter long before we did. 13:17: It’s rare on Earth, but if you lived on Venus you wouldn’t think of the supercritical fluid as a fringe state of matter at all. 14:22: So, let’s review all of the states of matter. 14:26: ... condensates and the resulting superconductors and superfluids; nuclear matter of various types; photonic matter; various spin-based states from ... 16:34: Some Kid and Cybernatural ask whether quasiparticles could be used to explain dark matter. 16:48: In other words, they exist in fields that arise from a volume being filled with matter. 16:53: Dark matter suffuses the near-vacuum of space, where we mostly just have the elementary quantum fields. 19:09: Quasars or “active galactic nuclei” glow from the heat energy of matter being ripped to shreds as it spirals towards a supermassive black hole. 02:55: And beyond it is an entirely new state of matter - the here-be-dragons of the phase diagram. 12:52: But Nature knew about this state of matter long before we did. 16:53: Dark matter suffuses the near-vacuum of space, where we mostly just have the elementary quantum fields. 00:43: I’m sure you know how states of matter work. 00:54: If you watched our episode on states of matter you’ll know it’s a bit more complicated than this.
	2022-12-08: How Are Quasiparticles Different From Particles? 04:44: In a sense that’s right - quasiparticles are emergent from the behavior of a particular configuration of matter. 04:51: ... like states of matter, which we talked about previously. But at the very least quasiparticles ...
	2022-11-23: How To See Black Holes By Catching Neutrinos 01:16: ... elementary particles are fermions - so particles of matter rather than force-carrying bosons like the photons of regular astronomy, ... 17:41: Originally it was thought that strange quarks were required, and we’ve been searching for strange quark matter since the ’80’s. 17:49: ... this may also be possible with the regular up and down quarks of normal matter, and that this up-down-quark matter may lead to perfectly stable “nuclei” ...
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 00:02: Half of the universe is filled with expansionist alien civilizations, and it’s only a matter of time before they’ll reach us.
	2022-10-19: The Equation That Explains (Nearly) Everything! 04:36: ... terms that each account for different ways the particles of both matter and force interact. And each of these terms is actually short-hand for a ... 05:37: ... be the most fundamental nature of a particle - whether it represents matter or ... 06:36: ... interact with each other. Alone, this describes a universe with no matter whatsoever. The Fs are actually shorthand for the separate interaction ... 09:24: ... make the universe more interesting by introducing some matter. That’s what the second term in the Lagrangian represents. The psi is the ... 09:45: ... preserve the symmetries of nature. This is the piece that tells us that matter and forces interact. The part with the EM field is equivalent to the ... 10:57: ... that make no sense. But it turns out that if you add a copy of the matter term but switch the sign in front of every imaginary number, all of the ... 12:39: ... up mass from the Higgs field, and it's pretty much the same as regular matter, as far as we ... 14:00: ... or its lagrangian. In fact there probably are - whatever makes up dark matter for example. And there are other mysteries that this doesn’t explain. It ... 10:57: ... that make no sense. But it turns out that if you add a copy of the matter term but switch the sign in front of every imaginary number, all of the ... 06:36: ... interact with each other. Alone, this describes a universe with no matter whatsoever. The Fs are actually shorthand for the separate interaction of each of ... 14:00: ... we discussed recently. And it doesn't explain dark energy or the matter-antimatter imbalance, among other things. And it is a bit of a mess. Many ...
	2022-09-21: Science of the James Webb Telescope Explained! 02:04: It was to be a much bigger scope that Hubble - because with telescopes size matters. 12:19: ... and then the one about how the Higgs boson could tell us what dark matter really ... 15:23: OK, on to our episode on how the Higgs boson could be the key to discovering the dark matter particle. 17:21: ... just get on with business and discover the big bang, dark matter and dark energy, and figure out how the universe is going to ... 15:23: OK, on to our episode on how the Higgs boson could be the key to discovering the dark matter particle. 02:04: It was to be a much bigger scope that Hubble - because with telescopes size matters.
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 00:19: But there are still many outstanding questions for example, it seems like nothing in the standard model can explain what dark matter is. 00:33: Many physicists think that the secret to finding the elusive dark matter particle will come by studying the Higgs. 00:49: The matter that we perceive out there in the universe is a small fraction of the matter that exists. 01:11: But there are other matter particles that interact only weakly, and so we don’t see them even though they’re insanely abundant. 01:31: And then there’s dark matter. 01:46: ... “dark matter” might be a new kind of particle, or, in fact, there could be an entire ... 02:37: This particular diagram shows a dark matter particle scattering off a standard model particle in some way. 02:44: The standard model particle could be a quark, an electron, or anything that makes up normal matter. 02:50: ... would call this a direct detection experiment - because a dark matter particle is actually interacted with one of the particles in our say ... 03:00: Of course this sort of interaction is incredibly rare - otherwise we’d have detected dark matter already. 03:06: But with enough particles and enough time, we should eventually see an interaction between a dark matter particle and a matter particle. 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays. 03:24: ... we have yet to spot even a single collision compatible with the dark matter particle ... 04:06: ... example, two dark matter particles somewhere in space could annihilate to produce gamma ray ... 04:18: If we were to find excess gamma radiation from high-density regions of our galaxy, then this might come from dark matter annihilations. 04:46: Now our annihilating dark matter. 04:48: ... become dark matter that’s created from the annihilation of some standard model particles. ... 05:10: In the LHC we smash together particles of regular matter, like protons or heavier nuclei. 05:35: But of all the particles produced in these events, we think that the elusive Higgs boson has the best shot at producing a dark matter particle. 06:30: ... could potentially decay into dark matter particles, but if they do it’s going to be near impossible to spot the ... 06:39: ... are ways to check whether dark matter and neutrinos are connected on cosmic scales by looking at the cosmic ... 06:55: ... Collider, but no evidence was found supporting interactions with dark matter, and so the Z is probably a dead ... 07:15: There’s good reason to think the Higgs might interact with dark matter. 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. 07:34: ... family of potential theories of how the Higgs could interact with dark matter, these all fall under the umbrella of Higgs portal ... 07:54: So, how exactly are we going to find dark matter via the Higgs? 08:14: But once we create them, how could we possibly tell if a Higgs decays into dark matter? 11:02: There are certain Higgs-generating reactions that are especially promising for our dark matter hunt. 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 13:08: ... Higgs physics, and we don’t know what it’ll reveal —- hopefully a dark matter particle, perhaps an entire dark sector, perhaps much ... 04:18: If we were to find excess gamma radiation from high-density regions of our galaxy, then this might come from dark matter annihilations. 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays. 11:02: There are certain Higgs-generating reactions that are especially promising for our dark matter hunt. 00:33: Many physicists think that the secret to finding the elusive dark matter particle will come by studying the Higgs. 02:37: This particular diagram shows a dark matter particle scattering off a standard model particle in some way. 02:50: ... would call this a direct detection experiment - because a dark matter particle is actually interacted with one of the particles in our say ... 03:06: But with enough particles and enough time, we should eventually see an interaction between a dark matter particle and a matter particle. 03:24: ... we have yet to spot even a single collision compatible with the dark matter particle ... 05:35: But of all the particles produced in these events, we think that the elusive Higgs boson has the best shot at producing a dark matter particle. 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 13:08: ... Higgs physics, and we don’t know what it’ll reveal —- hopefully a dark matter particle, perhaps an entire dark sector, perhaps much ... 03:24: ... we have yet to spot even a single collision compatible with the dark matter particle hypothesis. ... 02:37: This particular diagram shows a dark matter particle scattering off a standard model particle in some way. 01:11: But there are other matter particles that interact only weakly, and so we don’t see them even though they’re insanely abundant. 04:06: ... example, two dark matter particles somewhere in space could annihilate to produce gamma ray photons, which ... 06:30: ... could potentially decay into dark matter particles, but if they do it’s going to be near impossible to spot the event, so ... 06:19: ... not interacting with light is the first defining characteristic of dark matter.We aren’t left with much in the standard ...
	2022-08-24: What Makes The Strong Force Strong? 00:53: The protons on the other hand are packed together in the nucleus as tightly as any matter in the universe. 08:05: This allows quarks to move freely in a state of matter known as Quark Gluon Plasma. 17:19: ... Matter at that temperature forms a relativistic plasma, and we can produce such ... 17:31: We don’t see these plasmas actually freeze - just that their spectrum is changed a bit from the typical thermal spectrum of hot matter. 17:41: There’s also weird stuff, like the fact that there’s enough kinetic energy in this matter to cause spontaneous particle-antiparticle creation. 17:49: In general it’s a very difficult state of matter to do calculations on. 20:15: Others use this coupling to explain dark energy AND dark matter. 20:27: Speaking of which, Marik Zilberman asked whether a particle of the quintessence field could account for Dark Matter? 21:17: Everyone knows that dark matter shot JFK.
	2022-08-17: What If Dark Energy is a New Quantum Field? 02:31: ... attractive gravity due to its positive energy density, just like regular matter and energy do. But the effect of its negative pressure is more powerful, ... 03:33: ... it to mass by E=mc^2, you’d only get about a grain of sand’s worth of matter. That’s such a tiny amount that it doesn’t have any real effect in places ... 09:05: Alternatively, it can be thought of as a fifth energetic component of the universe on top of baryons, dark matter, neutrinos, and photons. 09:51: ... the energy in the universe is dark energy with the remaining 30% mostly matter, including dark ... 10:08: ... doesn’t sound very close, but it actually is. As the universe expands, matter dilutes away while most versions of dark energy stay constant or ... 10:55: ... could be coupled to the quantum fields responsible for radiation and matter, and its behavior could be connected to the density of the universe. For ... 03:33: ... any real effect in places where there’s even a smattering of regular matter - like inside our solar system, or even inside our galaxy. But if you ... 10:08: ... doesn’t sound very close, but it actually is. As the universe expands, matter dilutes away while most versions of dark energy stay constant or relatively ... 10:55: ... the cosmological constant problem. If quintessence shifts to match the matter fields, it could potentially cancel out their predicted extremely high vacuum ... 09:51: ... the energy in the universe is dark energy with the remaining 30% mostly matter, including dark ... 09:05: Alternatively, it can be thought of as a fifth energetic component of the universe on top of baryons, dark matter, neutrinos, and photons. 10:55: ... to the density of matter. And it only becomes dark-energy-like when matter starts to thin out. That provides a natural explanation for why dark energy ...
	2022-08-03: What Happens Inside a Proton? 14:58: ... on  Patreon there’s a link in the description.   And no matter what level you join at you’ll get access to our hopping discord as ... 15:29: ... Lerner tells us about another example of   different states of matter appearing on different hierarchical scales, and that example is ... 16:33: ... questions, but I guess you didn’t really have a choice in the matter. ... 16:44: ... always measure fully-up or fully-down,   no matter what direction the spin was initial prepared in. Its entangled ... 19:17: ... the  fun thing about determinism, is that   it doesn't matter. Either we have  free will or we don't and never did,   ... 15:29: ... Lerner tells us about another example of   different states of matter appearing on different hierarchical scales, and that example is plate ... 19:17: ... not the universe is deterministic, there's still only one question that matters,   "How can I abuse the rules of reality to  survive past the death of ...
	2022-07-27: How Many States Of Matter Are There? 00:00: OK kids, let’s talk about states of matter. 00:03: You know your states of matter don’t you? 00:05: We have solids, liquids and gasses, and plasmas, quark-gluon plasmas, nuclear matter, bose-einstein condensates, neutronium, time crystals, and sand. 00:17: Come to think of it, maybe I don’t know my states of matter. 00:21: Or what a state of matter even is. 00:31: ... know what a state of matter is. There's solids, there's liquids, there's gases - different states ... 01:15: So cool, states of matter are just the different, well, states that atoms can be in. 01:21: But wait, the quarks inside protons and neutrons are “matter”. 01:25: What is the state of matter of those? 01:28: Does it depend on the state of matter of the atoms they’re part of? 01:38: And then there are all those pop-sci media claims of “new state of matter discovered” - time crystals being a recent example. 01:47: To answer these questions, we better figure out what a state of matter really is. 01:51: ... you were to base your reasoning on the states of matter you learned in school - solid, liquid, and gas, and plasma for those who ... 02:55: For one thing, there are secret hidden states of matter. 03:29: A state of matter defines how these various average properties relate to each other. 03:44: Different states of matter have different equations of state. 03:47: ... relationships between the statistical properties of different states of matter is called ... 03:57: ... a state of matter determines and is determined by much more than the thermodynamic ... 04:28: ... general, we call some collection of stuff a state of matter if it has sufficiently unique set of emergent behaviors - like the ... 04:43: OK, so a state of matter is an emergent behavior due to the interactions between components under particular conditions. 04:50: Does that mean we can make different states of matter from things other than atoms? 04:55: Let’s start our search for some new states of matter by exploring in the direction we started. 05:44: This is our next state of matter. 07:00: The stuff of quarks is generically called quark matter or QCD matter - for quantum chromodynamics - the physics of quark and gluon interactions. 07:09: To fully convince you that quark matter has its own states of matter, behold its phase diagram. 07:24: Our quark-gluon plasma is actually the analogy of gas in atomic matter, even if it’s behavior is more liquid. 07:41: ... dissolve and we end up with really bizarre forms of liquid-like quark matter. ... 07:54: The states of matter we’re most familiar with can be explained as particles interacting under classical forces. 08:00: But once you bring quantum mechanics into the picture, many strange states of matter become possible. 08:07: ... example, in degenerate matter like neutronium or Bose-Einstein condensates, all quantum states are ... 08:21: Time crystals are the latest and perhaps weirdest quantum state of matter. 08:40: ... which makes them thermodynamically different than other states of matter - so they qualify as a state of matter of their ... 08:51: So it sounds like states of matter really are … exactly that - states of matter, rather than states of atoms. 08:58: Subatomic particles can have their own states of matter. 09:01: And it turns out that two completely different states of matter can exist simultaneously at different scales. 09:14: Different states of matter can be sort of nested within each other. 09:54: Here’s something we don’t usually think of as particles: human beings, but they can behave in ways eerily close to states of matter. 11:05: So, galaxies are fluids of stars which themselves are made of plasmas of hydrogen made of frozen nuggets of quark matter. 11:14: So if sand and crowds and galaxies exhibit behaviors that resemble states of matter are these really actual states of matter? 11:24: Not technically, but that’s really just a matter of convention. 11:28: The fact is, the concept of "states of matter" can help us to understand many kinds of interactions, even between macroscopic “particles”. 11:37: Max Tegmark from MIT has proposed that consciousness itself can be understood as a state of matter. 11:45: Just like the characteristic properties of a regular state of matter, the conscious mind is an emergent property of a type of information system. 12:09: ... of the mind as a state of matter allows us to use the tools of our material sciences - for example ... 12:28: ... definition of state of matter is somewhat slippery; its clear enough when we talk about the common ... 12:50: Just think of our universe as nested layers of states of matter, from the smallest to the largest scales of space time. 07:00: The stuff of quarks is generically called quark matter or QCD matter - for quantum chromodynamics - the physics of quark and gluon interactions. 08:40: ... which makes them thermodynamically different than other states of matter - so they qualify as a state of matter of their ... 07:09: To fully convince you that quark matter has its own states of matter, behold its phase diagram. 00:05: We have solids, liquids and gasses, and plasmas, quark-gluon plasmas, nuclear matter, bose-einstein condensates, neutronium, time crystals, and sand. 03:29: A state of matter defines how these various average properties relate to each other. 03:57: ... a state of matter determines and is determined by much more than the thermodynamic properties, ... 01:38: And then there are all those pop-sci media claims of “new state of matter discovered” - time crystals being a recent example. 00:03: You know your states of matter don’t you? 12:09: ... of our material sciences - for example quantum mechanics and condensed matter physics - to help us understand why we see the world the way we ...
	2022-07-20: What If We Live in a Superdeterministic Universe? 05:02: ... it doesn’t matter how far apart Alice and Bob’s labs are - across the campus or across the ...
	2022-06-30: Could We Decode Alien Physics? 02:25: ... rubbed off onto the cloth, so there’s a  flow of matter in the opposite direction.   You get a stronger shock from the ... 05:33: ... symmetric under charge conjugation - switch   all matter with antimatter and vice versa and the universe would keep ticking ... 10:41: ... are using. But again, this depends on our ability to distinguish matter   from anti-matter, so we still need to know which sign convention ...
	2022-06-22: Is Interstellar Travel Impossible? 07:30: None of those impacts are going to wipe the ship, but that may not matter. 17:31: ... is that yes, towards the singularity at the center of a black hole matter should reach arbitrarily high densities and energies - as high as is ... 03:07: For example, really REALLY big light sails, or compact fusion drives, or matter-antimatter engines.
	2022-06-15: Can Wormholes Solve The Black Hole Information Paradox? 02:24: ... have huge entropy because every black hole  looks the same no matter how it was ...
	2022-06-01: What If Physics IS NOT Describing Reality? 16:52: ... the expansion of the universe could be thought  of as matter shrinking rather than the universe   expanding. I took those ...
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 06:32: ... ago. This merger was so  large - around 50 billion Suns worth of matter -   that it must have reshaped the galaxy and can be  ... 12:11: ... solar masses due to the enormous amount of dark   matter it contains, making this easily the biggest meal the Milky Way has ... 17:21: ... regions. However those bound regions fell  together from matter that was initially   moving apart in the expanding universe, ... 18:41: ... shrinking. Jonathan Rose   has a similar hypothesis that all matter is  constantly shrinking within a static space.   Listen, ... 06:32: ... ago. This merger was so  large - around 50 billion Suns worth of matter -   that it must have reshaped the galaxy and can be  thought of as the ... 02:19: ... globular clusters.   But mostly the halo is made of dark matter,  which also suffuses the disk and halo   and constitutes 80% of ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 02:20: ... never-tiring giver of life, and in mythology,   matters of life and death often get the most  attention. This is why you ... 05:24: ... Milky Way where   life couldn’t possibly have formed, no  matter how perfect the host star. And   gues what - Moiya actually ... 02:20: ... never-tiring giver of life, and in mythology,   matters of life and death often get the most  attention. This is why you ...
	2022-05-04: Space DOES NOT Expand Everywhere 03:27: ... FLRW metric makes some pretty big assumptions - that the matter in the universe is perfectly evenly spread out - homogeneous, and it ... 05:19: ... of spacetime around massive objects is NOT the FLRW metric because the matter isn’t spread out evenly. For example, near a compact massive object the ... 11:59: ... when there’s an enormous amount of empty space compared to the amount of matter. But the ratio of empty space to matter inside galaxies doesn’t change. ... 05:19: ... of spacetime around massive objects is NOT the FLRW metric because the matter isn’t spread out evenly. For example, near a compact massive object the ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 02:31: ... phase - doesn’t affect measurable  quantities - only relative phase matters. ... 12:59: ... it shouldn’t be possible to tell where in the  valley you are. It matters if two adjacent   patches of the universe are in different ... 16:02: ... mechanism. The Higgs field also gives mass   to the matter particles - the fermions -  but that’s for another time. But what ... 02:04: ... transformations.   For example, physics works the same no matter  where you decide to center your x-y-z axes, or where you put the zero ... 02:31: ... phase - doesn’t affect measurable  quantities - only relative phase matters. ... 12:59: ... it shouldn’t be possible to tell where in the  valley you are. It matters if two adjacent   patches of the universe are in different ...
	2022-04-20: Does the Universe Create Itself? 09:08: ... say the rule is that Alice will answer yes and no alternately no matter what the question. So Bob asks, “is it smaller than a bread box?” “yes.” ... 15:24: ... flatten the universe because it’s a positive energy density, just like matter. But it’s negative pressure can allow even a closed universe to expand ... 17:39: ... of our observable universe - adding together all the stars, dark matter, other black holes, etc - then it’s event horizon is the same size as our ...
	2022-03-30: Could The Universe Be Inside A Black Hole? 00:28: Both of these involve matter being packed to infinite densities - they are singularities where the mathematics of GR breaks down. 00:58: Collapse any chunk of matter far enough and it gets stuck in its own gravity. 01:30: ... we think of as a point in time at the beginning of the universe when all matter was compressed to infinite density and all points in space ... 07:27: For one thing its made of pure spacetime - no matter included , and it;s highly inhomogeneous. 07:37: ... our universe appears to be highly homogeneous - matter and energy are very evenly spread out, and it was even more evenly ... 08:15: ... the collapse of a star by modeling it as a spherical cloud of matter with a perfectly homogeneous density and zero ... 08:36: ... an event horizon forms around it, but within the collapsing cloud the matter remains homogeneous and the spacetime is flat until it becomes a ... 07:27: For one thing its made of pure spacetime - no matter included , and it;s highly inhomogeneous. 08:36: ... an event horizon forms around it, but within the collapsing cloud the matter remains homogeneous and the spacetime is flat until it becomes a ...
	2022-03-23: Where Is The Center of The Universe? 02:16: Most importantly, this looks the same no matter what galaxy you’re in. 04:14: ... and flat.’ The exact shape is determined by the relative amounts of matter and dark energy in the ... 04:30: The presence of matter increases the curvature and the presence of dark energy decreases the curvature. 08:48: No matter the geometry of our FLRW universe, all geodesics converge to a single point in the past, and end there. 11:18: ... came up with his solution for the shape of the universe by assuming that matter and energy are evenly spread out ... 12:09: ... one of his solutions, matter was distributed with constant density across a spherically symmetric ... 04:30: The presence of matter increases the curvature and the presence of dark energy decreases the curvature.
	2022-03-16: What If Charge is NOT Fundamental? 14:52: My favorites are the fudge-filled hexaquarks, which are one of the most delicious candidates for dark matter. 03:02: ... in 1932 Heisenberg proposed a  new fundamental property of matter:   Isospin, a contraction of isotopic or isobaric spin, depending on who ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 19:51: ... and whether they could explain the cosmic microwave background and dark matter. ... 20:38: ... for dark matter - extremely unlikely - in our most accepted understanding of cosmic ... 20:48: But seriously guys one of the weird things we  talk about will turn out to be dark matter. 20:58: But let's hope it's never either. But  wait what if aliens are dark matter! 20:38: ... for dark matter - extremely unlikely - in our most accepted understanding of cosmic ...
	2022-02-16: Is The Wave Function The Building Block of Reality? 03:02: ... on the matter span all extremes. John von Neumann and Eugene Wigner thought that wave ... 08:02: ... like the frenetic Brownian motion of pollen grains floating on water. Matter’s interaction with this fluctuating field would continuously collapse the ... 08:32: ... just thought there was some mysterious field that interacted with all matter — almost like it was a fifth fundamental force. But Lajos Diósi and ... 16:15: ... the black hole event horizon is not from the point of view of falling matter, but from the point of view of a distant observer. Only the distant ... 16:48: ... that note Pesila Ratnayaje asks if an outsider observer sees matter slow and freeze at the event horizon, what happens when the event ... 16:15: ... the point of view of a distant observer. Only the distant observer sees matter approach a state of frozen time, and you’re right that from that person’s point ... 16:48: ... that note Pesila Ratnayaje asks if an outsider observer sees matter slow and freeze at the event horizon, what happens when the event horizon ... 03:02: ... on the matter span all extremes. John von Neumann and Eugene Wigner thought that wave ... 08:02: ... like the frenetic Brownian motion of pollen grains floating on water. Matter’s interaction with this fluctuating field would continuously collapse the ...
	2022-01-27: How Does Gravity Escape A Black Hole? 03:17: First we’ll see what Einstein has to say on the matter, and then we’ll go deeper, into the speculative realm of quantum gravity. 13:42: ... Badly drawn Turtle has an interesting thought on the matter and I quote: "That a small part of the wavefunction can be used to ... 16:57: ... matter what we put in for those unknown properties, the Milky Way & ...
	2022-01-19: How To Build The Universe in a Computer 00:47: ... and  hydrodynamic interactions of countless stars and gas and dark matter particles over billions of future ... 10:02: ... can watch as galaxies form, with gas and dark matter interacting to produce waves of star formation and supernovae, settling ... 10:28: It simulated 13-billion light years wide cube containing over 300 billion particles, each representing a billion-Suns worth of dark matter. 10:02: ... can watch as galaxies form, with gas and dark matter interacting to produce waves of star formation and supernovae, settling into spiral ... 00:47: ... and  hydrodynamic interactions of countless stars and gas and dark matter particles over billions of future ...
	2022-01-12: How To Simulate The Universe With DFT 09:59: ... states that if you have a system of electrons in their ground state, no matter how complicated, the properties of that system are uniquely determined ... 16:26: And for that matter, what about Jupiter. don’t read this asks about impacts on the Moon? 20:19: ... fact, will we even have a choice in the matter after the bitcoin mining AIs take over and cannibalize the world to ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 00:12: ... probably nonsense. And I imagined that it was just a matter of time before a black hole finally found its way to the Earth. So that ... 01:23: ... back then the universe had the same insane density everywhere - matter was smoothly spread out with only tiny density fluctuations. And so ... 01:49: ... it was the smoothness of the early universe that saved all of matter from collapsing into black holes. But that doesn’t mean that no black ... 02:10: ... of the mass of the universe, and are therefore an explanation for dark matter. ... 02:27: ... windows of possible masses if PBHs are to account for most of the dark matter. ... 03:25: ... for astronomers, and perhaps less fortunate for everyone else - if dark matter really is made of asteroid-mass black holes then there must be an ... 04:01: ... how much dark matter we know that there is in the Milky Way, we calculate that there's ... 04:26: ... hit the Earth we wouldn’t be destroyed - which is good, because if dark matter really is made of these things then it’s probably already happened. This ... 06:02: ... In the immediate surroundings of any black hole, gravity accelerates matter to incredible speeds. Near the event horizons, particles collide with ... 07:05: ... event horizon of a micro black hole is a very narrow choke-point for matter trying to flow in. Its Eddington limit is very low. For an asteroid-mass ... 11:02: ... stops very quickly, making something of a big round explosion, sending matter out in all directions. This makes a crater basin at the point of ... 13:02: ... could lead to figuring out the nature of dark matter and to understanding the crazy black-hole-spawning chaos that defined ... 14:10: ... was the one on modified newtonian dynamics as an explanation for dark matter, and the one on fuzzballs - the stringy theory version of the black ... 15:30: ... And that's that we’ve observed galaxies that seem to be >99% dark matter as well as a few that seem to lack it entirely. He asks whether the new ... 19:14: ... multidimensional - at least 3+1 in my experience. And for that matter all hairballs are technically quantum. This teaches us one important ... 11:02: ... set off. The result is that the crater may be much deeper, while the matter ejected around the crater goes more ‘up’ than ‘out’, and falls closer to the ... 01:49: ... have formed at the earliest of times, while still leaving plenty of matter left for ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... curiosity we really have to find out what is up with dark energy dark matter is cool but figuring out what dark energy really is it feels like ...
	2021-11-17: Are Black Holes Actually Fuzzballs? 00:20: ... Einstein’s general theory of relativity tells us that if the density of matter is sufficiently ridiculous, ultimate gravitational collapse is ... 00:39: ... matter should contract to a single point of infinite density - the singularity ... 01:14: ... the one hand, general relativity insists that no information from the matter that fell into a black hole should be observable on the surface - the ... 11:35: ... a fuzzball is forming, all of the matter - now dissolved into stringy mess, is pushed up to the surface and the ...
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 00:21: We’ve now been searching for dark matter for over half a century. 00:36: They would need at least 5 times as much  matter to provide the gravity needed to hold these galaxies together. 00:42: ... the gravity of visible matter is also way too weak to hold galaxy clusters together, or to bend the ... 01:02: ... dubbed this hypothetical stuff dark matter, and of course we’ve talked about dark matter many times on this channel ... 01:39: ... for nearly as long as astronomers have been hunting for dark matter, others have been hunting for an alteration to our theory of gravity that ... 02:32: ... matter is supposed to add extra mass that’s more evenly distributed through ... 02:43: Dark matter flattens rotation curves. 04:41: So MOND would need to do away with the need  for physical dark matter in the other places we see evidence for dark matter. 05:07: First, how does MOND do with respect to the other evidence for dark matter? 05:14: If you tune MOND to work for galaxies and then apply it to galaxy clusters, you do get rid of the need for some of the dark matter but not all of it. 05:22: You still need about 20% of the current dark matter requirement to explain all the gravity we see in clusters. 05:38: ... the fact that you still need some type of physical dark matter in clusters is seen as a strong point against MOND in its first ... 05:49: There are some other pieces of evidence for dark matter that O-G MOND also fails for, but I’ll come back to those. 06:47: ... a tight relationship because the rotation velocity depends on the dark matter halo  while the luminosity depends on the ... 10:21: One of the most important pieces of evidence  for dark matter as a particle is seen in the light that comes from the very early universe. 10:29: ... background radiation  reveals a lumpiness that tells us how matter pulled itself together under its  own gravity at the earliest ... 10:40: Back then, light and matter were locked  together due to the extreme densities. 10:44: Regular matter was kept from collapsing into  any structures by the pressure of the intense radiation of that era. 10:51: But dark matter doesn’t interact with light, so it would have been able to collapse just fine. 10:58: ... after the universe had expanded and cooled  enough for regular matter to be released from the clutch of light, it could have followed the dark ... 11:12: But if dark matter isn’t real, and regular matter controls gravity completely, then no structure should have been able to form at those early times. 11:45: ... in the early universe, that field behaved a bit like a type of matter, which Złosnik calls “dark ... 12:21: We don’t need dark matter, anymore? 12:33: ... I’ll just say that when galaxy clusters collide and the dark matter gets ripped away from the light matter - it makes you doubt that dark ... 13:10: ... MOND proponents say that it’s the behavior of  dark matter particles that have to be carefully fine-tuned to produce the phenomena ... 13:32: ... our experiments haven’t  detected dark matter yet, there are still plenty of possibilities for what it might be beyond ... 12:33: ... clusters collide and the dark matter gets ripped away from the light matter - it makes you doubt that dark matter is just light matter acting ... 11:12: But if dark matter isn’t real, and regular matter controls gravity completely, then no structure should have been able to form at those early times. 10:51: But dark matter doesn’t interact with light, so it would have been able to collapse just fine. 02:43: Dark matter flattens rotation curves. 06:47: ... a tight relationship because the rotation velocity depends on the dark matter halo  while the luminosity depends on the ... 11:12: But if dark matter isn’t real, and regular matter controls gravity completely, then no structure should have been able to form at those early times. 01:02: ... hypothetical stuff dark matter, and of course we’ve talked about dark matter many times on this channel - from the evidence for its existence to some of ... 13:10: ... MOND proponents say that it’s the behavior of  dark matter particles that have to be carefully fine-tuned to produce the phenomena that ... 10:29: ... background radiation  reveals a lumpiness that tells us how matter pulled itself together under its  own gravity at the earliest ... 05:22: You still need about 20% of the current dark matter requirement to explain all the gravity we see in clusters. 14:01: ... of reality, whether we’re led beyond the standard model by dark matter  particles, or beyond general relativity by hidden gravitational modes of ... 00:03: What if there is no such thing as dark matter.   What if our understanding  of gravity is just wrong? 10:01: ... and other MOND proposals produce  instabilities in the presence of matter,   which would, for example, make long-lived stars ...
	2021-11-02: Is ACTION The Most Fundamental Property in Physics? 01:22: ... property that could be minimized to determine the trajectories of matter as well as light? There were some efforts - for example Euler considered ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 00:02: Paradoxically, the most promising prospects for moving matter around faster than light may be to put a metaphorical brick wall in its way. 04:31: ... hard to even define what we mean by tunnelling time or time for that matter. ... 05:09: ... barrier, this ‘Hartman effect’ can effectively teleport real, physical matter between locations faster than it would take to travel that distance sans ... 16:01: And presumably if black holes had enormousmagnetic charges we’d see that in the way they interact with matter.
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 01:11: ... according to classical electromagnetism, it doesn’t matter how many times you slice it - you’ll never get isolated magnetic charges ... 10:13: ... care about the relative internal values of the Higgs field - what matters is the absolute length of that internal vector - not the direction it’s ...
	2021-09-21: How Electron Spin Makes Matter Possible 00:26: ... is the entire reason that stuff in our universe has structure, and that matter doesn’t immediately collapse. It’s the source of the Pauli exclusion ... 01:13: ... are called fermions, and include all the particles that we think of as matter - from electrons to quarks to the neutrinos. The other spin behavior is ... 14:26: ... there you have it - matter has structure and you don’t fall through your chair because electrons ... 14:58: ... indistinguishable or degenerate. That makes you some exotic form of matter, presumably unbound by the laws of known physics. So thank you for ... 01:13: ... are called fermions, and include all the particles that we think of as matter - from electrons to quarks to the neutrinos. The other spin behavior is to ... 00:26: ... is the entire reason that stuff in our universe has structure, and that matter doesn’t immediately collapse. It’s the source of the Pauli exclusion principle, ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 00:00: ... the weirdest place in the modern universe  - a place where matter exists in states   that I bet you’ve never heard of. Today we ... 01:02: ... And it’s time we did so, because there we’ll find states of matter that exist nowhere else in   the universe. For this journey ... 04:04: ... we start to encounter the first truly strange states of matter. See, the matter at your feet is   not all that different from ... 04:39: ... into a regular grid. In this case the crystalline   matter is mostly iron. That iron was the last  element forged in the core ... 08:15: ... pasta. This is perhaps the least known and most freaky state of matter in the universe.   When nuclei start to touch they rearrange, ... 09:34: ... Nuclear physicists affectionately call this phase  of matter spaghetti. At slightly higher densities,   this nuclear ... 11:14: ... pasta layer, just above the neutron star core,   all that matter has been smooshed together into a soup of mostly neutrons and just ... 12:23: ... if they exist in neutron stars. The only other time   matter existed naturally in conditions like these was within a fraction of ... 13:06: ... the surface. It seems our neutron star has started accreting matter from a binary partner star.   Its mass is growing and at some ... 12:23: ... if they exist in neutron stars. The only other time   matter existed naturally in conditions like these was within a fraction of a ... 00:00: ... the weirdest place in the modern universe  - a place where matter exists in states   that I bet you’ve never heard of. Today we ... 04:04: ... the fermion family can’t occupy   the same quantum state. The matter has  become what we call degenerate, and electron   degeneracy ... 09:34: ... Nuclear physicists affectionately call this phase  of matter spaghetti. At slightly higher densities,   this nuclear spaghetti may be ... 02:00: ... sun.   It’s filled with electrons and  positrons. These matter-antimatter   pairs are created out of the extreme  energy photons in the ... 07:06: ... kilometer deep, and we’re at least a trillion times the density of matter   on Earth. We are really relying on our theoretical calculations ...
	2021-09-07: First Detection of Light from Behind a Black Hole 10:12: ... also have winds of matter flowing at incredible speeds - but this close to the black hole only the ...
	2021-08-18: How Vacuum Decay Would Destroy The Universe 00:21: ... quantum fields give rise to the particles   that make up all matter and all forces - and  if those quantum fields were a bit ... 07:01: ... of similarities with the sort of phase transitions that you get in matter.   For example, when water boils - it undergoes a phase transition to ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 16:27: ... And then guesses the correct answer - it dissipates into space with the matter, potentially leading to electromagnetic radiation. And that is exactly ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 06:21: ... white dwarfs, matter is crushed so close together that the inward gravitational pull is ... 07:24: ... when you add mass to less weird space-stuff, say a planet or a star. The matter inside is crushed closer together until there’s enough pressure to ... 08:29: ... that and the matter gets packed so close together that one of two things happen. If a dying ... 17:08: ... the answer I just gave - can magnetic fields be used to explain dark matter or to explain dark energy? Or could magnetic fields be used to power ... 07:24: ... when you add mass to less weird space-stuff, say a planet or a star. The matter inside is crushed closer together until there’s enough pressure to resist the ...
	2021-07-21: How Magnetism Shapes The Universe 11:47: Those fields grab particles of matter and accelerate them to incredible energies, flinging cosmic rays out into the universe.
	2021-07-07: Electrons DO NOT Spin 01:26: ... of particles - a property that is responsible for the structure of all matter. We’ll unravel all of that over a couple of episodes - but today we’re ... 13:30: ... more interesting. The thing we call spin is a clue to the structure of matter - and maybe to the structure of reality itself through these things we ... 15:31: ... hand, the extreme smoothness meant that the entropy associated with matter was extremely  high. Energy was as spread out as it could get ... 17:44: This is very disrespectful, and I intend to write a series of op-eds to correct the matter. 13:30: ... more interesting. The thing we call spin is a clue to the structure of matter - and maybe to the structure of reality itself through these things we ... 15:31: ... they could move. The low gravitational entropy massively outweighed the matter entropy,  so entropy was low. That smoothness seems to suggest the particles of ... 13:00: ... table, for electrons  living in their own energy levels and for matter   actually having structure. It’s the reason you don’t fall through the ...
	2021-06-09: Are We Running Out of Space Above Earth? 13:34: ... worry, we’ll keep doing this no matter what - but I gotta give a huge shoutout to the Patreon crew - you guys ... 14:14: Last episode was on Planck Relics, those subatomic scale black holes that could be literally everywhere and even explain dark matter. 14:25: Matt Kelly asks what happens to normal matter when it interacts with one of these tiny black holes. 14:31: Well first of all, Planck relics would be so impossibly tiny that all matter would be like empty space to them. 14:38: Give them any velocity at all and they stream right through matter as though it isn’t there. 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? 08:19: ... from primordial black holes is that these could potentially explain dark matter. ... 08:28: Plank relics are really perfect candidates - they’d be completely invisible no matter how many of them were.. 08:35: And you’d need a lot to say the least because dark matter makes up 80% of the mass of the universe. 09:02: ... explaining Dark Matter, another reason to want Planck relics to be a thing is that they may ... 10:15: Then all that information would have plenty of room to exist, no matter the size of its package. 10:41: If Planck relics account for all of dark matter, are they around us right now?
	2021-05-11: How To Know If It's Aliens 12:35: ... fact is, no matter now long we study the universe, it will always come up with natural ... 14:35: ... our update on warp drive theory, and the one about whether dark matter can be explained by enormous numbers of black holes - tldw - it probably ... 17:14: ... points out that there are scientists who have pushed the black hole dark matter hypothesis for years, so it hasn’t been overlooked as I implied at the ... 17:34: ... biology. Which is that the answer often lies in plurality. Dark matter might not be a single type of thing, but rather many different types of ... 18:02: ... geniuses, many of you commented that you thought of the idea that dark matter is black holes years ago. That’s impressive - you’re in the company of ... 18:16: ... matter ain’t black holes. That may have sounded unnecessarily snarky - and it ... 18:32: ... But it doesn't, hurt to check. I like this a lot. Looking for dark matter in, say, string theory, before you check whether it’s black holes is ... 18:16: ... matter ain’t black holes. That may have sounded unnecessarily snarky - and it wasn’t ... 17:14: ... points out that there are scientists who have pushed the black hole dark matter hypothesis for years, so it hasn’t been overlooked as I implied at the beginning of ...
	2021-04-21: The NEW Warp Drive Possibilities 04:11: ... then ran it backwards through the equations to see what distribution of matter and energy would be ... 04:59: ... people talk about the drive requiring negative mass - also called exotic matter - and yeah, that would do the trick too - and is also probably ... 05:11: ... original field required more energy than is contained in all the matter in the visible universe to move a moderate-sized ... 05:30: ... the requirement of exotic matter didn’t go away, and in fact subsequent studies demonstrated that any ... 07:47: But all these guys agree that superluminal bubbles are only possible if the warp field uses exotic matter. 09:45: ... field the warp is in front and behind the spaceship, while the exotic matter is in a ring around the direction of ... 12:04: So far there’s no known way to do this, and warp fields may suffer the same strict speed limit as does matter. 04:59: ... people talk about the drive requiring negative mass - also called exotic matter - and yeah, that would do the trick too - and is also probably ... 05:30: ... the requirement of exotic matter didn’t go away, and in fact subsequent studies demonstrated that any ...
	2021-04-13: What If Dark Matter Is Just Black Holes? 00:09: Sounds horrible - but hey, at least we’d have explained dark matter. 00:25: This is dark matter, and it is one of the universe’s most perplexing mysteries. 00:30: ... days most dark matter hunters are trying to hypothesize or detect exotic new particles to ... 00:44: ... of gravity - the general theory of relativity - that might explain dark matter’s influence without the need for actual ... 01:03: What if dark matter is just black holes? 01:06: These hyper-dense holes in the fabric of spacetime seem to be great dark matter candidates - being so black and holey and all. 01:25: ... seems like a significant point in their favor as an explanation for dark matter - it’s more than we can say for any of the other dark matter particle ... 01:39: ... dark matter makes up roughly 80% of the mass of the universe, but it’s much more ... 01:53: ... for black holes to be dark matter they’d need to be abundant enough to make up all of this mass, and ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 02:28: We have, of course, been trying to find evidence for black hole dark matter for some time. 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. 02:50: Our hypothesis is that dark matter is made of black holes. 02:53: ... gaps left - whether it’s still possible for black holes to explain dark matter. ... 03:47: ... enough supernovae to give us enough black holes to make up all of dark matter. ... 03:57: Also, if dark matter is produced as stars die, you’d expect its influence to increase over time. 04:03: But we know that dark matter has been with us from the very beginning. 04:07: ... in the cosmic microwave background tell us that the gravity of dark matter was pulling matter together long before the first stars ever ... 04:18: So if dark matter is made of black holes then those black holes must have been with us from the beginning. 04:35: Now, we’ve talked about them before, but let’s dig much deeper into the question of whether primordial black holes could explain dark matter. 04:53: ... know there were regions of the early universe that had a bit more matter than other regions - we see that in the cosmic microwave background from ... 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. 05:53: Dark matter can’t be made of these or anything close to because they tend to fall to the centers of their galaxies pretty quickly. 06:17: We can also rule out black holes a bit larger than this as dark matter. 06:20: ... dark matter to be made of black holes with masses around that of a larger asteroid ... 07:30: Probably no more than a few percent of the dark matter mass can be from these micro black holes. 07:40: At this point, gravitational lensing becomes the go-to method for dark matter hunters. 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 08:41: The very first MACHO microlensing events were detected, but there weren’t nearly enough to account for dark matter. 08:52: ... mass to 10 or so times the mass of the Sun as a main contributor to dark matter. ... 09:07: ... even if MACHOs aren’t all of dark matter, studies of the Magellanic Clouds and Andromeda have found enough ... 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: ... 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 microlensing ... 10:11: ... structures of dwarf galaxies tells us that no more than 4% of the dark matter could be black holes of tens to thousands of solar ... 10:37: We have some evidence ruling out most of the black hole mass spectrum as the main source of dark matter. 10:43: ... and frankly it's unlikely that it just so happens that all dark matter is packed into the spots we haven’t properly looked at ... 10:57: ... dark matter probably isn’t black holes - but don’t be sad - that means dark matter ... 11:27: These so-called Planck relics are bad news as dark matter - because they’re essentially undetectable. 11:39: Whatever the case, dark matter is freaky stuff, fitting as the main material ingredient of our generally freaky space time. 01:25: ... seems like a significant point in their favor as an explanation for dark matter - it’s more than we can say for any of the other dark matter particle ... 01:39: ... of the mass of the universe, but it’s much more spread out than regular matter - for example, in our galaxy it forms a vast halo around twice the ... 09:37: ... 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 microlensing ... 11:27: These so-called Planck relics are bad news as dark matter - because they’re essentially undetectable. 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 01:06: These hyper-dense holes in the fabric of spacetime seem to be great dark matter candidates - being so black and holey and all. 00:30: ... days most dark matter hunters are trying to hypothesize or detect exotic new particles to explain the ... 07:40: At this point, gravitational lensing becomes the go-to method for dark matter hunters. 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. 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 07:30: Probably no more than a few percent of the dark matter mass can be from these micro black holes. 01:25: ... for dark matter - it’s more than we can say for any of the other dark matter particle ... 09:07: ... even if MACHOs aren’t all of dark matter, studies of the Magellanic Clouds and Andromeda have found enough microlensing ... 00:44: ... of gravity - the general theory of relativity - that might explain dark matter’s influence without the need for actual ...
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 14:09: For example, based on the amount of matter and dark energy, we can figure out now much the expansion should have slowed or sped up.
	2021-03-16: The NEW Crisis in Cosmology 10:08: ... into the distribution of galaxies that formed from that matter. The Baryon acoustic oscillations seem   to be coming on the ... 14:47: ... because we don't really know what time is. Nor space for that matter - or whether they're really   the same type of thing - ...
	2021-03-09: How Does Gravity Affect Light? 12:17: It’s a matter of perspective, and how you define your reference frames.
	2021-02-24: Does Time Cause Gravity? 10:35: ... of those waves with matter right after inflation may have caused characteristic patterns in the ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... balls 20 kilometers across and that extreme density converts all of the matter into neutrons they are on the edge of absolute collapse into black holes ...
	2021-02-10: How Does Gravity Warp the Flow of Time? 01:45: John Archibald Wheeler put this notion the most pithily: Spacetime tells matter how to move; matter tells spacetime how to curve. 02:22: Matter tells space AND time how to curve, and it’s the curvature of time that’s mostly responsible for telling matter how to move. 04:14: And, in fact, to any matter - anything that can experience time, which in practice means anything with mass. 04:48: ... speed of light is always measured to be the same for all observers, no matter their personal ... 08:25: The source of acceleration doesn’t matter. 11:03: ... the photon - or whatever light-speed quantum components make up matter - actually do have to travel further - between mirrors or between the ... 11:14: So that photon clocks and matter do evolve more slowly in gravitational fields. 11:51: The curvature of space by matter isn’t nearly enough to give gravity at the strength we feel it. 04:14: And, in fact, to any matter - anything that can experience time, which in practice means anything with mass. 11:03: ... the photon - or whatever light-speed quantum components make up matter - actually do have to travel further - between mirrors or between the ... 11:51: The curvature of space by matter isn’t nearly enough to give gravity at the strength we feel it. 01:45: John Archibald Wheeler put this notion the most pithily: Spacetime tells matter how to move; matter tells spacetime how to curve. 02:22: Matter tells space AND time how to curve, and it’s the curvature of time that’s mostly responsible for telling matter how to move. 01:45: John Archibald Wheeler put this notion the most pithily: Spacetime tells matter how to move; matter tells spacetime how to curve.
	2021-01-26: Is Dark Matter Made of Particles? 00:00: By the time I finish this sentence, up to a billion billion dark matter particles may have streamed through your body like ghosts. 00:23: ... see the influence of dark matter in the orbits of stars and galaxies, in way light bends around galaxies ... 00:33: It’s become disturbingly clear that we can’t see around 80% of the matter in the universe. 00:39: Even more disturbing is that there doesn’t even seem to be a candidate for dark matter in the known family of particles. 01:07: When we talk about the “dark sector” we typically mean a particle or family of particles that contribute to dark matter. 01:13: Now it’s possible that dark matter is not particles - it could be black holes or failed stars or even weirder so-called “compact objects”. 01:20: It might even be that what we perceive as dark matter is really a glitch in the laws we use to describe gravity. 02:58: The main requirement for a dark matter particle is that it doesn’t “speak electromagnetism”. 03:17: No, dark matter is both perfectly dark AND perfectly transparent. 03:27: ... matter can’t have charge but it must have mass because the only thing we’ve ... 03:38: Dark matter “speaks gravity”. 03:45: ... can map where dark matter is found by how it affects the rotation of galaxies, and how it drives ... 03:58: These tell us something really important: dark matter is far more spread out - more diffuse - than almost all of the visible matter. 04:07: And that tells us a lot about any prospective dark matter particle. 04:10: For one thing, dark matter doesn’t tend to interact with itself - at least not very much. 04:15: If it did, then giant regions of dark matter would lose energy in those collisions and contract. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 04:25: But no - dark matter seems to stay puffed up in gigantic halos surrounding the much more concentrated clumps of visible matter. 04:34: In fact, galaxies are really just shiny dustings of stars, sprinkled deep in the gravitational wells of massive reservoirs of dark matter. 04:42: But the fact that dark matter forms those giant halos at all tells us something very important. 04:48: It gives dark matter a temperature. 04:51: More accurately, it tells us how far dark matter particles were able to travel in the early universe. 04:57: ... “free-streaming length” of dark matter is how far a dark matter particle could travel before interacting with ... 05:16: Now, based on how that structure did end up forming, it seems likely that dark matter was moving pretty slowly. 05:22: We refer to such dark matter as “cold”. 05:25: ... let’s review - if dark matter is a particle, it’s electrically neutral and doesn’t interact much with ... 05:35: For a long time people thought the neutrino might be dark matter - being neutral and the most abundant known particle in the universe. 05:52: ... but actually gets physicists very excited - because discovering a dark matter particle may be our best for finding a bigger, deeper theory than the ... 06:14: Dark matter hunters come in two breeds. 06:42: Actually, we don’t have to go too far beyond the standard model to find our first dark matter candidate. 06:47: Completely independently of our quest for dark matter, physicists have hypothesized a new type of neutrino - the so-called sterile neutrino. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 07:41: So to account for dark matter they’d need to exist in prodigious numbers … but according to pro-axion physicists, that may well be the case. 07:52: Explorations of the theoretical landscape have led physicists to multiple possibilities for dark matter particles. 08:01: We’ve also talked about supersymmetry, but not about how it could give us dark matter. 08:07: ... the standard model which proposes that all the regular particles - both matter and force-carrying - have twins - counterparts on the opposite side of ... 08:18: Every matter particle or fermion has a supersymmetric force-carrier, or boson. 08:42: ... simplest kind of dark matter we get from supersymmetry is called a ‘neutralino.’ It’s a sort of ... 09:03: ... particles then they’d be stable and long lived- an almost perfect dark matter ... 09:15: ... are other dark matter candidates in different flavours of supersymmetry - all of them “LSPs” - ... 09:26: ... is eerily close to the mass expected for a certain type of dark matter - which some would say is a point in favor of ... 09:45: ... dark matter particles like the neutralino are examples of a general dark matter ... 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. 10:17: We also covered weakly interacting - it helps dark matter halos stay puffed up. 10:22: ... it also turns out that the interaction strength of dark matter is extremely important - it may have governed how every interesting ... 11:36: ... need to have in order to survive in sufficient numbers to give us dark matter. ... 12:17: Because dark matter is weakly-interacting, our light sector is probably more complex - probably. 05:35: For a long time people thought the neutrino might be dark matter - being neutral and the most abundant known particle in the universe. 09:26: ... is eerily close to the mass expected for a certain type of dark matter - which some would say is a point in favor of ... 06:42: Actually, we don’t have to go too far beyond the standard model to find our first dark matter candidate. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 09:15: ... are other dark matter candidates in different flavours of supersymmetry - all of them “LSPs” - for ... 04:10: For one thing, dark matter doesn’t tend to interact with itself - at least not very much. 04:42: But the fact that dark matter forms those giant halos at all tells us something very important. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 10:17: We also covered weakly interacting - it helps dark matter halos stay puffed up. 06:14: Dark matter hunters come in two breeds. 02:58: The main requirement for a dark matter particle is that it doesn’t “speak electromagnetism”. 04:07: And that tells us a lot about any prospective dark matter particle. 04:57: ... “free-streaming length” of dark matter is how far a dark matter particle could travel before interacting with something - typically another such ... 05:52: ... but actually gets physicists very excited - because discovering a dark matter particle may be our best for finding a bigger, deeper theory than the standard ... 08:18: Every matter particle or fermion has a supersymmetric force-carrier, or boson. 09:03: ... particles then they’d be stable and long lived- an almost perfect dark matter particle. ... 09:45: ... dark matter particles like the neutralino are examples of a general dark matter particle type called the WIMP, or “weakly interacting massive ... 00:00: By the time I finish this sentence, up to a billion billion dark matter particles may have streamed through your body like ghosts. 04:51: More accurately, it tells us how far dark matter particles were able to travel in the early universe. 07:52: Explorations of the theoretical landscape have led physicists to multiple possibilities for dark matter particles. 09:45: ... dark matter particles like the neutralino are examples of a general dark matter particle type ... 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. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 06:47: Completely independently of our quest for dark matter, physicists have hypothesized a new type of neutrino - the so-called sterile neutrino. 03:38: Dark matter “speaks gravity”. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people.
	2021-01-19: Can We Break the Universe? 11:44: ... no matter how fast the spaceship travels, it will only elongate along this helix - ... 12:16: ... geometries that inspired this episode - guys, i hope this helped clarify matters a ... 02:41: ... way around and its nose smashes into its tail, presumably puncturing the matter-antimatter tanks and destroying the ... 12:16: ... geometries that inspired this episode - guys, i hope this helped clarify matters a ...
	2020-12-22: Navigating with Quantum Entanglement 12:32: Or confuse matters far worse- it remains to be seen.
	2020-12-15: The Supernova At The End of Time 03:43: ... for example, had discovered a new, theoretical state of ultra-dense matter - degenerate matter - in which atoms are stripped of their electrons, ... 04:07: Unable to get any closer, the electrons in degenerate matter exert a powerful outward pressure - electron degeneracy pressure. 04:32: ... realized they could be composed of his degenerate matter, and that degeneracy pressure alone would be enough to stop them from ... 08:29: ... slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over around 10^1500 ... 03:43: ... for example, had discovered a new, theoretical state of ultra-dense matter - degenerate matter - in which atoms are stripped of their electrons, and ... 08:29: ... slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over around 10^1500 ... 03:43: ... for example, had discovered a new, theoretical state of ultra-dense matter - degenerate matter - in which atoms are stripped of their electrons, and then those ... 08:29: ... slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over around 10^1500 ... 04:07: Unable to get any closer, the electrons in degenerate matter exert a powerful outward pressure - electron degeneracy pressure.
	2020-12-08: Why Do You Remember The Past But Not The Future? 12:23: ... highlights a real mystery with the big bang theory The distribution of matter and energy in the early universe does appear to have been random - which ... 12:58: ... early universe the low entropy was not in the degrees of freedom of the matter - that stuff was high entropy when taken separately, but rather in the ...
	2020-11-18: The Arrow of Time and How to Reverse It 11:16: ... not even in principle learnable by some snooping entity, then it doesn’t matter whether they were generated in our brains or in the big bang. The effect ... 13:36: ... back to matters quantum. Zahaquiel reminded us of the best proof regarding quantum ...
	2020-11-11: Can Free Will be Saved in a Deterministic Universe? 01:14: ... you accept that the mind is generated by the brain, which is made of matter, and you've already accepted that matter follows the cold inviolable laws ... 03:34: ... networks of these threads may spend time as different types of matter and sometimes as brains, both as the crude matter that forms the brain ... 07:28: I'll argue shortly that there's a notion of free will in which it doesn't matter the origin of the unpredictability of choice. 13:01: When you ask, is free will an illusion, what do you mean by free or will or illusion or is, for that matter?
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 02:50: By the way, force-mediating particles are bosons, as opposed to the fermions that make up matter.
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 01:17: ... a surface where time froze.   Beneath that “event horizon” all matter, light, space itself was doomed to fall inwards towards a ... 01:58: ... solution  didn’t say anything about HOW   a clump of matter could reach the densities  high enough to produce an event horizon ... 04:06: ... and a singularity would form for any distribution of matter, no matter how messy, as long as that   matter was compacted ... 01:17: ... a surface where time froze.   Beneath that “event horizon” all matter, light, space itself was doomed to fall inwards towards a central   point. ... 01:58: ... to produce an event horizon - nor   even whether such dense matter would  really contract into a single point.   It only showed that, ... 05:01: ... is gravitational lensing. Gravitational  fields produced by regular matter   always produce this convergence. It would take negative mass or ... 01:17: ... published them,   revealing that a sufficiently dense ball of matter would be surrounded by a surface where time froze.   Beneath that ...
	2020-10-13: Do the Past and Future Exist? 09:47: In front of the future light cone is the region that is in the future for everyone, no matter what their speed.
	2020-10-05: Venus May Have Life! 06:33: Well, although phosphine can be produced in a number of different ways, it rarely lasts long no matter how it’s made.
	2020-09-21: Could Life Evolve Inside Stars? 00:00: Science fiction has come up with countless ideas for weird forms of life not based on boring old DNA, or even on matter as we know it. 00:08: There’s Stanislaw Lem’s sentient ocean in Solaris, or the neutron star civilization made of nuclear matter in Robert L Forward’s Dragon’s Egg. 03:11: These transitions were analogous to the phase transitions between states of matter - for example, water freezing into ice.
	2020-09-08: The Truth About Beauty in Physics 06:45: ... representation of a single datum of experience.” In other words, no matter how pretty and parsimonious our theory, if it doesn’t match reality as ...
	2020-08-24: Can Future Colliders Break the Standard Model? 04:09: ... top quark, and so enabled the discovery of the final Fermion - or matter particle - in the standard ... 07:00: It doesn’t seem to give us a particle that could explain dark matter. 04:09: ... top quark, and so enabled the discovery of the final Fermion - or matter particle - in the standard ...
	2020-08-17: How Stars Destroy Each Other 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova. 05:05: ... combine to become neutrons, and you’re left with a ball of hyperdense matter the size of a ... 12:12: ... black holes may have formed from the extremely dense matter of the early universe, and these would have different mass restrictions ... 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova.
	2020-08-10: Theory of Everything Controversies: Livestream 00:00: ... theories to have with quantum field theory and so i think it's a matter of what you take it there is this experience a personal experience ...
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... that i think that are foundational that i think physicists no matter how bright we think we are and how it's too hard and elegant and all ...
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 05:01: ... innermost part of the core turned into an ultradense nugget of matter while the rest of the infalling core rebounded causing the supernova ... 05:11: So you end up with at least one and a half suns worth of matter locked in a ball that would fit inside a small city. 05:51: If only you could cram a little more matter into the neutron star, the escape velocity would increase and it would become a black hole. 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. 06:13: But neutron stars are NOT made of normal matter. 07:19: ... because the calculations required to understand the bizarre states of matter in a neutron star are horrendous, and there’s still some stuff that we ... 07:31: That’s especially true towards the center of the neutron star, where the neutrons themselves probably break down into different types of quark matter. 07:49: ... details of the state of matter in the neutron star determines how a neuron star’s size changes with ... 09:12: If it IS a neutron star then it puts us at the theoretical limit, and can tell us a lot about the crazy states of matter inside. 10:52: But if it IS a neutron star then we’ve learned a ton about the most extreme states of matter in the universe. 11:08: Each will be rich in information on the nature of stars, and gravity, and strange quantum states of matter. 13:53: A couple of you asked why we think there had to be an actual imbalance in the number of antimatter versus matter particles in the early universe. 14:19: Matter and antimatter would have been smoothly mixed, and there’s no mechanism to separate them. 09:12: If it IS a neutron star then it puts us at the theoretical limit, and can tell us a lot about the crazy states of matter inside. 05:11: So you end up with at least one and a half suns worth of matter locked in a ball that would fit inside a small city. 13:53: A couple of you asked why we think there had to be an actual imbalance in the number of antimatter versus matter particles in the early universe.
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 00:22: ... so on. And when a particle encounters its anti-particle patrner - when matter encounters anti=matter- the two can pair-annihilate, canceling each ... 01:25: ... answer seems to be that the universe started out with a little more matter compared to anti-matter. If there were slightly more particles than ... 02:51: ... we expect it to treat antimatter in exactly the same way as regular matter. ... 03:38: ... CP violation may have contributed to the asymmetry of matter and anti-matter in the early universe, in a process called “electroweak ... 03:58: But remember that antimatter is what you get when you do a full CPT transformation of matter. 04:05: ... really IS violated however it may explain why we live in a universe of matter, and would undo a lot of what we think we know about quantum mechanics. ... 04:48: ... of the universe is incomplete. It doesn’t explain dark energy, dark matter, or this baryon asymmetry problem. So, if there exists some underlying ... 05:19: ... demands that an anti-particle must have the exact same properties as its matter counterpart, besides the charge and spin thing — it must have the same ... 06:00: ... can be created in particle accelerators - just by smashing regular matter together. The problem is, antimatter immediately annihilates with any ... 08:39: ... and so drifted to the walls of the trap where it annihilated with the matter it ... 09:19: ... of the vacuum. Any difference in these properties in anti-matter versus matter will cause a shift in the laser frequency necessary to stimulate a ... 10:56: ... pretty sure anti-matter interacts with gravity in the exact same way as matter, but why not test ... 11:51: ... that leads to matter-antimatter imbalance and to the fact that we have matter in the universe at all. Maybe it’ll come from CPT violations measurable ... 12:37: ... antimatter. But Kristie, you can’t be antimatter because obviously you matter very, very much to someone. We’ll keep working on the cake, but in the ... 01:25: ... are around a billion times more photons than there are particles of matter - so we estimate that for every billion particles of matter that ... 05:19: ... demands that an anti-particle must have the exact same properties as its matter counterpart, besides the charge and spin thing — it must have the same mass, the same ... 00:22: ... so on. And when a particle encounters its anti-particle patrner - when matter encounters anti=matter- the two can pair-annihilate, canceling each other out ... 11:51: ... idea of where to look for this strange BROKEN symmetry that leads to matter-antimatter imbalance and to the fact that we have matter in the universe at all. ...
	2020-06-30: Dissolving an Event Horizon 09:23: A charged black hole in the vicinity of any matter would repel like charges and attract and swallow opposite charges, and so quickly neutralize. 09:32: But imagine we create a charged black hole and isolate it from all other matter.
	2020-06-22: Building Black Holes in a Lab 11:04: ... some ways, the crux of the matter is as much philosophy as physics: How much can analog black holes ...
	2020-06-15: What Happens After the Universe Ends? 02:23: But let me try to give you a sense of a situation where scale might not matter. 02:54: Let’s say these universes contain no matter - only photons - light. 07:06: ... - black holes will evaporate by Hawking radiation, and particles of matter will decay into their lightest possible ... 11:03: Penrose also says that CCC naturally gives you dark matter - but we’ll skip that for now. 17:36: Not that it matters, we know one of the critters is going to sneak in by infecting one of the astronauts and, like, controlling their mind. 02:54: Let’s say these universes contain no matter - only photons - light. 11:03: Penrose also says that CCC naturally gives you dark matter - but we’ll skip that for now. 17:36: Not that it matters, we know one of the critters is going to sneak in by infecting one of the astronauts and, like, controlling their mind.
	2020-06-08: Can Viruses Travel Between Planets? 13:58: ... law for gravity holds on the cosmic scales if we haven’t explained dark matter yet, which originated from the apparent failure of the inverse square ... 14:11: In other words, maybe the inverse square law breaks down on large scales, producing the illusion of dark matter. 14:32: Two issues with this idea: MONDS fails to get rid of the need for all dark matter. 14:44: ... we have other evidence of dark matter - for example in gravitational lensing, in the cosmic microwave ...
	2020-05-18: Mapping the Multiverse 11:58: This would be okay-ish if the black hole was empty, but it’s not okay if there’s even the tiniest bit of matter or radiation.
	2020-05-11: How Luminiferous Aether Led to Relativity 09:26: ... aether wind was blowing one way or the other - but actually none of that matters. You’d see the bright bands of the interference pattern at the locations ... 11:20: ... that now allowed the speed of light to remain constant, no matter your ... 09:26: ... aether wind was blowing one way or the other - but actually none of that matters. You’d see the bright bands of the interference pattern at the locations ...
	2020-05-04: How We Know The Universe is Ancient 11:07: ... value of 13.8 billion years, you need to take into account the effect of matter slowing down expansion through its gravity and also the effect of dark ... 12:25: ... the gold standard for measuring the age of the universe is to get the matter content, and the dark energy content, and the expansion rate, and more ... 12:59: ... map produced by the Planck satellite we get the relative amounts of matter and dark energy and a number of other quantities. Quantities important ... 11:07: ... there actually is. The mass of the universe - which is mostly in dark matter - can be found by adding up the gravitational effect in galaxies and in ... 12:25: ... the gold standard for measuring the age of the universe is to get the matter content, and the dark energy content, and the expansion rate, and more all from ... 11:07: ... value of 13.8 billion years, you need to take into account the effect of matter slowing down expansion through its gravity and also the effect of dark energy ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... the event horizon slightly distorted due to the effects of the extra matter how is that related well Bob dead in that question just solved the ...
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 02:34: ... because the wormhole throat would remain the same, very short length no matter how far apart its ends ... 05:17: ... black hole represented here is a so-called “eternal” black hole - no matter where you are in the universe, if you travel to the left at any possible ... 07:52: ... of spacetime, and any topology. The only limitation is the nature of the matter and energy that spacetime contains. In fact by defining the geometry you ... 08:42: ... common way to think of exotic matter is anything with negative energy density. Something with negative mass ... 09:11: In general, exotic matter violates the so-called energy conditions of general relativity. 10:15: ... by constructing a number of wormhole geometries that kept the exotic matter out of the way of travelers. For example, he devised a sort of cubic ... 11:03: ... physics has not yet ruled out its existence, exotic matter threatens horrible causal paradoxes. Many physicists believe it can’t ... 11:48: ... example of a potentially traversable wormhole that may not need exotic matter - and that’s the wormhole through a rotating or charged black hole. Now ... 12:17: ... for wormholes in general - perhaps as big as the requirement of exotic matter. To create a shortcut between two regions of space, the topology of that ... 12:51: ... foam and amplify it to macroscopic scales, stabilizing it with exotic matter. ... 14:59: ... satellite. Leo also asks whether these bubbles might be caused by dark matter interactions with the black hole. I'm afraid I don't know of any theory ... 11:48: ... example of a potentially traversable wormhole that may not need exotic matter - and that’s the wormhole through a rotating or charged black hole. Now ... 10:15: ... For example, he devised a sort of cubic wormhole - wires of exotic matter define sharp edges, while space is relatively flat and safe for travel on the ... 07:52: ... In fact by defining the geometry you want - eg a wormhole - the required matter distribution is automatically given. Kip Thorne and his student Michael Morris ... 08:42: ... class of weirdness than that. Thorne and Morris describe a type of matter exerting an outward pressure capable of holding open the wormhole, but without ... 10:15: ... It turns out there are lots of ways to make wormholes... if exotic matter exists at ... 14:59: ... satellite. Leo also asks whether these bubbles might be caused by dark matter interactions with the black hole. I'm afraid I don't know of any theory of dark ... 11:03: ... physics has not yet ruled out its existence, exotic matter threatens horrible causal paradoxes. Many physicists believe it can’t exist, if ... 09:11: In general, exotic matter violates the so-called energy conditions of general relativity.
	2020-04-14: Was the Milky Way a Quasar? 02:19: ... using the Fermi Gamma-ray Space Telescope to look for evidence of dark matter in the innermost regions of the Milky ... 02:33: ... astronomers believe that when dark matter particles crash into and annihilate each other, the result could be a ... 02:42: We have of course covered dark matter and dark energy in detail previously. 02:54: Dark matter has the property that it tends to spread out diffusely and evenly. 03:06: Gamma rays produced by dark matter annihilations should have similar structure. 08:37: Sagittarius A* would have converted matter to energy with much less efficiency. 03:06: Gamma rays produced by dark matter annihilations should have similar structure. 02:33: ... astronomers believe that when dark matter particles crash into and annihilate each other, the result could be a fireworks ...
	2020-03-24: How Black Holes Spin Space Time 06:48: ... of the otherwise insanely bright accretion disk formed by infalling matter. And that’s because any gas that gets that close will quickly be ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 07:15: ... atom flips between two states. The nature of those two states doesn’t matter as long as it doesn’t change the spin or sap energy from the electron. ... 13:47: ... entangled particles maintain their correlations, no matter how far separated in boring old space ...
	2020-03-03: Does Quantum Immortality Save Schrödinger's Cat? 12:03: ... Goswami points out that the different matter configurations between experimental aparatus and the brain of different ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 11:41: ... those wavefunction branches corresponds to a specific configuration of matter and information - in the computer and in your ...
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 08:40: Even Erwin Schrodinger, in his 1958 lectures Mind and Matter states that consciousness is needed to make physical reality meaningful. 13:01: ... about the hypothetical particle that might solve the mystery of dark matter - if we could just detect the ... 13:39: There were a couple of questions and comments on the discord about how axions could be dark matter - aren't they too fast moving? and too light? 14:19: Sure, each would be very light, but their could be enough of them to perfectly account for dark matter. 14:26: ... the comments: if axions come from stars, would galaxies lose their dark matter and fly apart once the stars ... 14:45: If axions are dark matter then it would have to be the primordial axions - the ones formed in the big bang. 14:51: ... 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 see in stars, which ... 13:01: ... about the hypothetical particle that might solve the mystery of dark matter - if we could just detect the ... 13:39: There were a couple of questions and comments on the discord about how axions could be dark matter - aren't they too fast moving? and too light? 14:51: ... 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 see in stars, which is ... 08:40: Even Erwin Schrodinger, in his 1958 lectures Mind and Matter states that consciousness is needed to make physical reality meaningful.
	2020-02-11: Are Axions Dark Matter? 00:51: ... may explain a much more famous conundrum. The axion may explain dark matter. ... 11:08: ... there’s a good reason for the effort: axions may be ... dark matter. They have all the right properties - no direction interaction with ...
	2020-02-03: Are there Infinite Versions of You? 00:26: ... not; it could turn out that the universe contains enough matter and energy to close in on itself and be finite, or perhaps the simplest ... 15:08: ... of time is irrelevant from the perspective of the virtual photon - what matters is the structure of the ... 16:02: ... it said out loud, but by then it's stuck in your head that way no matter how many times you get corrected you still say it that ... 15:08: ... of time is irrelevant from the perspective of the virtual photon - what matters is the structure of the ...
	2020-01-27: Hacking the Nature of Reality 01:30: ... fact the great Neils Bohr passionately advocated it, insisting that matters are the observables - the measurable start and end points of an ... 07:36: ... example of this is the fact that antimatter can be treated as matter traveling backwards in time - that folds together large sets of Feynman ... 01:30: ... fact the great Neils Bohr passionately advocated it, insisting that matters are the observables - the measurable start and end points of an ...
	2020-01-20: Solving the Three Body Problem 01:49: ... equations will then give you the state of the system at that time, no matter how far in the past or future. We call such a simple, exactly-solvable ... 14:52: Nexus void asks how we’ll learn if neutrinos prefer to interact with matter or antimatter. 14:57: ... what we’ll do is a little different. We want to see if matter or antimatter neutrinos change their identity at different rates. We do ...
	2020-01-13: How To Capture Black Holes 12:17: ... in which you can make an arbitrarily gigantic universe from very little matter and that is inflation, in which the rapid exponential expansion of space ...
	2020-01-06: How To Detect a Neutrino 01:08: ... (text) "Deep Underground Neutrino Experiment" is to study whether or not matter and antimatter actually act ... 01:15: ♪ ♪ As you know from E=mc^2, matter and antimatter should be the same, ♪ ♪ and they're not. 04:24: ... ((𝘴𝘰𝘧𝘵)) ♪ MATT (voiceover): In order to interact with other types of matter, a neutrino needs to ♪ (𝘩𝘪𝘨𝘩 𝘴𝘺𝘯𝘵𝘩 𝘸𝘩𝘪𝘯𝘦 𝘧𝘢𝘥𝘦𝘴 𝘪𝘯) ♪ exchange one of the ... 07:26: ... hopefully, tell us something fundamental about the difference between matter and antimatter ♪ ♪ Which, also hopefully, will tell us why we live in a ... 07:38: ... (voiceover): Our best understanding of particle physics tells us that matter and antimatter ♪ (𝘭𝘰𝘸 𝘦𝘯𝘥 𝘰𝘧 𝘴𝘺𝘯𝘵𝘩 𝘧𝘢𝘥𝘦𝘴) ♪ should have been created in ... 07:51: ... ♪ The fact that we see a universe full of matter ♪ (𝘷𝘰𝘭𝘶𝘮𝘦 𝘣𝘶𝘪𝘭𝘥𝘴, 𝘴𝘺𝘯𝘵𝘩 𝘴𝘵𝘳𝘪𝘯𝘨 𝘱𝘭𝘶𝘤𝘬 𝘧𝘢𝘥𝘦𝘴 𝘰𝘷𝘦𝘳) ♪ means there must have ... 08:06: ... must have been a tiny asymmetry ♪ (𝘭𝘰𝘸 𝘴𝘸𝘦𝘭𝘭) ♪ between the behavior of matter and ... 08:31: ... neutrinos in the early universe may have decayed into other matter particles, ♪ ♪ with matter neutrinos producing antimatter particles, ♪ ♪ ... 08:46: ... neutrinos, ♪ ♪ that could lead to an ultimate imbalance in the amount of matter versus ... 08:54: ... oscillating between the three different types more slowly than matter ... 08:31: ... early universe may have decayed into other matter particles, ♪ ♪ with matter neutrinos producing antimatter particles, ♪ ♪ and antimatter neutrinos - or ... 08:54: ... oscillating between the three different types more slowly than matter neutrinos. ... 08:31: ... early universe may have decayed into other matter particles, ♪ ♪ with matter neutrinos producing antimatter particles, ♪ ♪ and antimatter neutrinos - or anti-neutrinos - ... 08:46: ... neutrinos, ♪ ♪ that could lead to an ultimate imbalance in the amount of matter versus ...
	2019-12-09: The Doomsday Argument 03:48: Weinberg calculated that the density of dark energy should most typically be observed to be around 5-10 times the density of matter. 03:57: That was in the early to mid 90s, right before dark energy was actually discovered and found to be around three times that of matter. 14:29: ... a universe like ours where matter and energy is evenly distributed on the largest scales the curvature ... 14:50: That said, patchs of the universe CAN change in curvature depending on the behavior of matter in those patches.
	2019-12-02: Is The Universe Finite? 01:38: ... large and geometrically flat, and is dominated by the influences of dark matter and a constant density of dark ... 06:41: See, gravitational lensing is caused by mass - both dark matter and atoms. 06:56: ... new study claims there’s enough extra matter revealed by that lensing to actually close the universe into a finite ... 07:53: Does that mean there’s enough matter to cause it to re-collapse again? 06:56: ... new study claims there’s enough extra matter revealed by that lensing to actually close the universe into a finite hypersphere ...
	2019-11-11: Does Life Need a Multiverse to Exist? 04:18: ... chemical interactions give us different states of matter and a vast family of molecules, which in turn are capable of forming ... 08:25: ... elementary particles, is just right for things like stars and complex matter to form in our ... 09:04: ... all of space and whose oscillations produce the familiar particles of matter or radiation, were expected to have a so-called zero-point ...
	2019-11-04: Why We Might Be Alone in the Universe 02:18: So no matter how rare these you-supporting environments really are - by definition you’re in one.
	2019-10-21: Is Time Travel Impossible? 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. 06:14: In short – if you have exotic matter you can probably time travel. 08:20: His involved an entire universe, rotating about a central axis and with matter and dark energy perfectly balancing it against collapse or expansion. 10:33: As long as the backwards time-traveling configuration of matter always leads to exactly to the same forward-traveling configuration.
	2019-10-07: Black Hole Harmonics 09:53: ... doesn’t matter what fell in to make the black hole – atoms, photons, dark matter, ...
	2019-09-30: How Many Universes Are There? 09:37: The real timescale is going to be much more fuzzy than this, but it also doesn’t really matter for this argument.
	2019-08-26: How To Become an Astrophysicist + Challenge Question! 03:35: ... good foundation in the fundamentals of modern physics It doesn't really matter what you major in but by the time you've taken all of that physics you ...
	2019-08-19: What Happened Before the Big Bang? 07:01: ... that will lead to very small density and temperature fluctuations in the matter produced after ...
	2019-08-12: Exploring Arecibo in VR 180 00:13: ... a rock hurtling through the vast solar system did it learn mastery over matter and the forces of nature and built cities and spaceships? and this ...
	2019-08-06: What Caused the Big Bang? 00:43: ... solve some of the biggest questions in cosmology, those being: why is matter and energy so smoothly spread out across the entire observable ... 02:37: They describe how its expansion or contraction depend on the matter and energy it contains. 10:59: ... the rest of the Big Bang story predicts: An extremely hot dense ocean of matter and radiation that slowly cools and disperses and forms structure as the ...
	2019-07-25: Deciphering The Vast Scale of the Universe 07:32: ... assembled into many vast filaments, flowing together on rivers of dark matter to form the cosmic web, of which Laniakea is just a ...
	2019-07-18: Did Time Start at the Big Bang? 00:05: But only for the right definition of our universe and "started" for that matter. In fact, the Big Bang is probably nothing like what you were taught. 01:56: ... can see pretty much directly that all space and matter in the universe was once crunched at least a thousand times closer ... 04:32: Do that enough times and any two points, no matter how far apart they were, will end up as close together as you'd like. 09:52: ... idea was the Big Bounce in which the Gravitational attraction of all matter in the universe was enough to cause it to re-collapse and then ...
	2019-07-15: The Quantum Internet 05:21: ... allow faster-than-light communication nor teleportation of actual matter, because a classical, sub-light-speed channel is still needed to extract ... 08:01: ... we need for this final step, but all of this is definitely possible with matter ... 09:07: ... typically means transferring a quantum state between a photon and a matter particle – say, an electron whose up or down spin direction can be ... 10:14: These are great because they’re much, much faster than repeaters that have to transfer quantum states between photons and matter particles. 10:34: ... photons can then transfer their entangled states into a variety of matter storage systems, which may eventually serve as repeaters to extend the ... 09:07: ... typically means transferring a quantum state between a photon and a matter particle – say, an electron whose up or down spin direction can be entangled with ... 10:14: These are great because they’re much, much faster than repeaters that have to transfer quantum states between photons and matter particles. 08:01: ... we need for this final step, but all of this is definitely possible with matter qubits. ... 10:34: ... photons can then transfer their entangled states into a variety of matter storage systems, which may eventually serve as repeaters to extend the range and ...
	2019-07-01: Thorium and the Future of Nuclear Energy 00:33: ... the other end of the spectrum is the energy released when particles of matter and antimatter are brought together They annihilate each other releasing ...
	2019-06-20: The Quasar from The Beginning of Time 01:50: ... sky. Astronomers guessed the speck was a quasar - a vortex of radiant matter falling into a giant black ... 06:24: ... used to measure redshift are also broadened due to the extreme speeds of matter moving near the black hole. That allows us to estimate the mass of the ... 01:50: ... sky. Astronomers guessed the speck was a quasar - a vortex of radiant matter falling into a giant black ... 06:24: ... used to measure redshift are also broadened due to the extreme speeds of matter moving near the black hole. That allows us to estimate the mass of the black ...
	2019-06-17: How Black Holes Kill Galaxies 00:08: ... a shock they were discovered as the driving force behind Quasars where matter is heated to extreme Incandescence before it plunges into vast Black ... 01:35: ... itself depends on the total mass of the Galaxy including Dark Matter so why shouldn't a Galaxy and its Black Hole be closely connected A ... 02:54: ... understanding of Physics of the Universe especially the nature of Dark Matter and Dark Energy we expect 'Bottom up Galaxy formation' this is what we ... 13:04: Tricky asks us why we don't see more strange matter from neutron star collisions. 13:12: ... actually "Strange Stars" whose nuclear material is composed of strange matter which means up, down, and strange ... 13:24: If such a star was disrupted, then we would expect to see blobs of strange matter in the debris. 13:30: ... the thing is, strange matter is probably only stable under extreme pressure Release it from the ... 13:47: Even if strange matter is stable as so called "Strangelets" These are electrically neutral, so they don't have an electromagnetic signature. 13:56: By the way, you wouldn't actually "see" strange matter. 02:54: ... the densest parts of the Universe Places where enormous worlds of Dark Matter pulled in great rivers of material from all around gas poured into the clusters ...
	2019-06-06: The Alchemy of Neutron Star Collisions 02:47: ... to think of neutrinos as ghostly particles that barely interact with matter but here both the neutrino and matter densities are so high that our new ... 12:15: ... Westrich summarizes my feelings on the matter: "it's amazing how much scientists can find out with so little in this ... 02:47: ... that barely interact with matter but here both the neutrino and matter densities are so high that our new nucleons can ride this neutrino wind to freedom ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 13:23: Then we’ll also need a quantum internet … which we know how to do in theory, but it’s a different matter to actually build one. 14:46: ... from the last two videos - our episode on the galaxy without dark matter, and our coverage of the event horizon telescope's black hole ... 14:57: AspLode asks about the interaction between dark matter and black holes. 15:02: Can dark matter form a black hole? 15:04: ... assuming that dark matter is some sort of exotic particle - which is the going hypothesis - then ... 15:19: One of dark matter's definig qualities is that it doesn't clump together - it remains diffusely spread out through our galaxy. 15:27: Occasional dark matter particles would be snared by black holes - and they would add to its mass just like regular matter. 15:35: But dark matter alone could never clump together densely enough to produce a black hole by itself. 15:02: Can dark matter form a black hole? 15:04: ... is the going hypothesis - then black holes would definitely attract dark matter gravitationally, and occationally eat the ... 15:27: Occasional dark matter particles would be snared by black holes - and they would add to its mass just like regular matter. 15:19: One of dark matter's definig qualities is that it doesn't clump together - it remains diffusely spread out through our galaxy.
	2019-05-01: The Real Science of the EHT Black Hole 05:21: In this case it’s the energy released by matter falling into the black hole.
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... been failing to detect dark matter for decades but finally the latest failure to detect Dark Matter may ...
	2019-04-10: The Holographic Universe Explained 12:21: The techniques of AdS/CFT correspondence are even extended to disparate fields like nuclear and condensed matter physics.
	2019-04-03: The Edge of an Infinite Universe 07:05: ... matter must originate at this point representing all of space in the infinite ... 11:56: The boundary is infinitely far away and looks the same no matter where we travel. 17:49: ... it starts to disrupt the way chemistry works, without actually ripping matter ... 18:09: To make matters worse, the Earth would be falling apart at the same time.
	2019-03-28: Could the Universe End by Tearing Apart Every Atom? 03:05: ... decelerate the universe to cause it to recollapse. In fact for regular matter the effective density is much higher than the effective pressure the ...
	2019-03-20: Is Dark Energy Getting Stronger? 00:04: ... and is built on the idea about the behavior of Dark Energy and Dark Matter. ... 00:29: Subtle clues are emerging that the accepted model for the nature of dark energy and dark matter may not be all that. 02:22: Those same textbooks talk about dark matter – an invisible stuff whose gravitational influence overwhelms all types of visible matter combined. 02:40: ... of study and calculation suggest that dark matter is a particle of some unknown type, cold, diffuse, and immune to ... 02:51: ... the textbooks, this type of cold dark matter sits alongside the cosmological constant as our best description of how ... 03:02: Constant dark energy, cold dark matter – or the Lambda-CDM model. 03:19: ... starting conditions of the universe – the balance of dark energy, dark matter, and everything else at the earliest of times when the CMB was released ... 05:32: Perhaps the cosmological constant is not so constant, or dark matter is not so cold after all. 06:44: When matter falls too close to a black hole, it forms a superheated vortex pouring into the black hole – an accretion disk. 02:22: Those same textbooks talk about dark matter – an invisible stuff whose gravitational influence overwhelms all types of visible matter combined. 06:44: When matter falls too close to a black hole, it forms a superheated vortex pouring into the black hole – an accretion disk. 02:51: ... the textbooks, this type of cold dark matter sits alongside the cosmological constant as our best description of how the ...
	2019-02-20: Secrets of the Cosmic Microwave Background 01:34: ... differences result from tiny variations in the density of matter right after the big bang which evolved as colossal sound waves ... 01:47: ... painted a simplistic picture A quick review In the very beginning Dark matter flowed towards tiny regions of increased ... 02:05: ... by gravity Regular matter, what we call baryons was in plasma form with the simple atomic nuclei ... 07:42: ... the angles of a triangle add up to 180 degrees However the presence of matter and energy as well as cosmic expansion cause geometry to be curved which ... 11:14: ... which represent the smallest fluctuations These tell us about the dark matter Well more accurately they tell us about the relative amount of dark ... 12:34: ... the amount of baryons and the higher peaks give you the amount of Dark Matter Combining this, we can separate the relative contents of all three ... 11:14: ... Well more accurately they tell us about the relative amount of dark matter compared to radiation, or light Now this is a bit too much of a rabbit hole for ... 02:05: ... those were just the right size were caught at maximum density matter concentrated in the middle of the fluctuation or at minimum density with matter at ... 12:34: ... because we get approximately the same numbers when we look at the dark matter content in modern galaxies and clusters and the dark energy based on measuring ... 01:47: ... painted a simplistic picture A quick review In the very beginning Dark matter flowed towards tiny regions of increased ... 11:14: ... radiation-dominated epoch Basically photons produced more gravity than matter Fluctuations that were small enough to oscillate at least once during this brief time ...
	2019-02-07: Sound Waves from the Beginning of Time 00:11: ... form constellations, Hidden patterns that echo the reverberations of matter and light From an epoch long before galaxies ever ... 01:57: These particles of matter are our baryons. 02:26: We say that in this state, light was coupled with matter, And baryons and photons formed a single strange fluid: A Baryon-Photon plasma. 02:36: There are three profound differences between the behaviour of matter in this state Compared to the gentle gas nebula of the modern universe. 03:16: Mixed in this soup of baryons and photons was dark matter. 03:21: ... fact, dark matter outweighs baryons by a factor of five, Which means it was, by far, the ... 03:31: But unlike baryons, dark matter does not interact with light at all. 03:35: Light exerts no pressure on dark matter. 03:38: Okay, so, the universe is filled with this hot ocean of baryons, photons, and dark matter. 03:51: ... teensy bit more matter here, or a teensy bit less there, These fluctuations probably were the ... 04:13: Each over-dense region pulled gravitationally on its surroundings, gravitationally on its surroundings, drawing matter towards it. 04:19: In particular, the dark matter flowed inwards towards this density peak. 04:52: ... matter became more diffused, and the photons themselves were stretched, ... 05:39: As a result, light and matter were no longer coupled. 06:33: While all of this was happening, dark matter was doing its own thing. 06:37: Immune to the radiation pressure, the central dark matter overdensity had continued to grow It pulled on the expanding shell, and was pulled by it. 06:46: ... the expanding wave froze, both dark matter and baryons flowed together and consolidated the new structure. Once ... 09:27: ... in the centers of those primordial density fluctuations, where the dark matter was the most ... 10:10: That's the clustering from the giant dark matter density peaks. 10:21: These are the galaxy pairs where one is at the center of the dark matter peak, and one is on the surrounding ring. 16:40: It can also be used to explain dark energy and dark matter. 10:10: That's the clustering from the giant dark matter density peaks. 04:19: In particular, the dark matter flowed inwards towards this density peak. 06:46: ... the new structure. Once more in the gravitational grip of dark matter, hydrogen and helium could begin the long work of collapsing into stars and ... 03:21: ... fact, dark matter outweighs baryons by a factor of five, Which means it was, by far, the dominant ... 06:37: Immune to the radiation pressure, the central dark matter overdensity had continued to grow It pulled on the expanding shell, and was pulled by it. 10:21: These are the galaxy pairs where one is at the center of the dark matter peak, and one is on the surrounding ring.
	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. 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. 11:52: ... the sign of the acceleration when any force is applied to exotic matter, and it also means flipping the sign of its kinetic and potential ... 12:04: Push exotic matter and it simultaneously accelerates towards you and loses kinetic energy.
	2019-01-24: The Crisis in Cosmology 01:45: ...of the matter and energy it contains,... 08:01: In the era just before the release of the CMB, matter and light were trapped together. 08:06: Matter wanted to collapse under its own gravity,... 08:32: ...the release of the CMB meant that light and matter were no longer coupled together. 09:02: This, in turn, depends on the density of matter and radiation,... 09:21: Those parameters include the starting combination of both dark and light matter, and radiation,... 11:53: Two: Dark matter particles behave differently to how we thought. 11:57: Perhaps dark matter interacts more strongly with matter and radiation,... 13:02: ...to investigate the mysterious physics of dark energy, dark matter,... 13:29: ...as a unifying explanation of both dark matter and dark energy. 14:03: ...the gravitational lensing measurements of dark matter... 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. 14:32: And yeah, those measures tell us that dark matter has positive mass I'd need to do the simulations, but I have a feeling... 14:44: ...if the effect of dark matter was due to this dark fluid. 17:17: ...frankly, I'm not sure, because we don't know the state of matter in the black hole. 17:46: He reveals to us that dark energy equals dark matter,... 11:57: Perhaps dark matter interacts more strongly with matter and radiation,... 11:53: Two: Dark matter particles behave differently to how we thought. 08:06: Matter wanted to collapse under its own gravity,...
	2019-01-16: Our Antimatter, Mirrored, Time-Reversed Universe 03:02: ... in the nuclei of our now anti cobalt-60 and other anti-atoms sending matter to antimatter is the C part of cpt charge conjugation all charges switch ... 10:20: Matter that was going forward in time looks like parity flipped antimatter going backwards in time. 10:26: ... interpretation of antimatter as time reverse matter was first proposed by Ernst Stueckelberg in 1941 but is now largely ... 10:54: ... is also violated and we see this violation in the asymmetry between matter and antimatter then there's the whole entropy business although it's ... 13:52: ... to why string theory is right I'll reiterate my real opinion on the matter after addressing fill strengths specific than very reasonable ... 03:02: ... in our clock will align antimatter nuclei in the opposite direction to matter nuclei so in our mirror reflected antimatter clock the direction of the decay ...
	2019-01-09: Are Dark Matter And Dark Energy The Same? 00:07: Dark energy AND dark matter? 00:22: ... Oxford just published a paper suggesting that both dark energy and dark matter may result from the same ... 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 01:08: As with any new theory combining dark matter and dark energy, probably it helps to know what they are first. 01:18: So, dark matter: the galaxies are spinning too fast. 01:23: Based on the gravity from visible matter alone they shouldn’t be able to hold themselves together. 01:31: So we conclude that galaxies, and for that matter the universe, has 5-10 times as much matter as we can actually see. 01:39: We call it dark matter, and try as we might we can’t find the presumably-exotic particle that constitutes it. 03:50: Jamie Farnes was looking for a way to get an anti-gravitational effect that explained both dark energy AND dark matter. 06:05: That’s a bizarre situation, but as I’ll explain in a moment it’ll give us our dark matter replacement. 06:11: In fact let’s start with dark matter because that’s a bit more straightforward. 08:10: That gives a positive pressure, and in general relativity positive pressure adds an attractive gravitational force, no matter what causes it. 08:35: The direct effect is repulsive – antigravitational – which I guess was the original motivation for using negative matter. 10:31: Those supernova results suggest a universe that started expanding rapidly and then slowed down due to the gravity of matter – mostly dark matter. 11:47: ... energy density, when added to the energy of both regular and dark matter, are needed to explain this spatially flat ... 11:57: If you replace both dark energy and dark matter with negative-energy stuff, then the universe becomes negatively curved. 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 06:05: That’s a bizarre situation, but as I’ll explain in a moment it’ll give us our dark matter replacement.
	2018-12-20: Why String Theory is Wrong 16:28: ... the cpt theorem tells us and we'll get back to that real soon and yes if matter from that Mirror Universe broke through and came into contact with ours ...
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... laws will still give the balls trajectory those laws work the same no matter the direction of motion in fact if we rotate the whole mirror balls ...
	2018-11-21: 'Oumuamua Is Not Aliens 14:35: ... passing through matter, interactions with the electromagnetic field change the effect of mass of ...
	2018-11-14: Supersymmetric Particle Found? 00:28: Historically, no matter how crazy our theories got, there were always new ways to test them. 01:46: ... by introducing a new symmetry between the fermions, which comprise matter, and the bosons, which communicate the fundamental ... 05:30: They can pass through solid matter.
	2018-11-07: Why String Theory is Right 10:09: Turns out that in 4D spacetime it does matter whether you change the scale of space and the separation of its tracks.
	2018-10-31: Are Virtual Particles A New Layer of Reality? 00:21: Near black holes, virtual matter and antimatter pairs are separated by the event horizon to create Hawking radiation. 11:11: ... painted a picture of virtual matter-antimatter pairs being separated by the black hole event horizon, allowing one of ...
	2018-10-18: What are the Strings in String Theory? 04:31: If wiggly strings can explain force-carrying bosons, why not also the fermions that comprise matter? 14:53: Our supermassive black hole computer is only large enough to contain all information in radiation and matter.
	2018-10-10: Computing a Universe Simulation 03:48: ... the same time, the actual information content in matter and radiation is probably more like 10 to the power of 90 bits, roughly ... 04:28: We'll figure out the case for just matter and for matter and radiation. 05:55: ... you want to include photons, neutrinos, dark matter, et cetera, and not just atoms, you need to scale up the surface area by ... 10:12: Matter and radiation combined have an entropy of 10 to the power of 90 bits.
	2018-10-03: How to Detect Extra Dimensions 02:38: But before we get all hyper-dimensional, let's think a bit more about 3 plus 1D space-time and how gravity, light, and matter behave there. 05:48: But you restrict all the other stuff in the universe-- matter, radiation, astronomers-- to only three spatial dimensions. 06:55: ... your theory just right, and you get normal physics for matter and radiation in three spatial dimensions-- for example, the usual ... 02:38: But before we get all hyper-dimensional, let's think a bit more about 3 plus 1D space-time and how gravity, light, and matter behave there. 05:48: But you restrict all the other stuff in the universe-- matter, radiation, astronomers-- to only three spatial dimensions.
	2018-09-12: How Much Information is in the Universe? 00:25: ... then there's all the stuff that isn't stars-- the dark matter, black holes, planets, and the particles, and radiation in between the ... 06:34: So almost all of the information, and for that matter, the entropy in particles is in neutrinos and in the cosmic microwave background photons. 06:42: The situation with dark matter is unclear, so let's just round up to 10 to the power of 90 bits of information in particles in our universe. 08:04: So the Milky Way's black hole has as much entropy and hidden information as all of the matter and radiation in the entire rest of the universe. 10:03: Also ignore dark matter. 10:04: Just regular matter like protons, electrons, et cetera. 00:25: ... then there's all the stuff that isn't stars-- the dark matter, black holes, planets, and the particles, and radiation in between the stars ...
	2018-09-05: The Black Hole Entropy Enigma 02:05: What they realized is that it doesn't matter what material goes into one. 11:00: That also means that the information needed to describe any volume of space, no matter its contents, is proportional to the area bounding that space.
	2018-08-30: Is There Life on Mars? 11:17: ... called kerogens, which are often produced in the decay of once living matter. ... 12:33: It's a simple matter of drilling 1.5 kilometers into the Martian ice cap to investigate.
	2018-08-23: How Will the Universe End? 03:55: The universe contains nothing but cold, dark nuggets of superdense matter. 04:05: But neutron stars and white-- or, by now, black-- dwarfs are made of degenerate matter. 04:11: This is matter that is fully collapsed in a quantum mechanical sense. 08:33: By the way, dark matter will probably also be long gone by now. 08:38: ... though we don't know exactly what it is, dark matter particles will likely either annihilate themselves as they collide with ... 09:54: ... the remaining matter in the universe, quantum tunneling allows the elements lighter than iron ... 11:14: ... that's the case, then all matter larger than a dust grain will collapse into a black hole in around 10 to ... 11:33: If they do, then matter is kaput much earlier. 11:14: ... that's the case, then all matter larger than a dust grain will collapse into a black hole in around 10 to the ... 08:38: ... though we don't know exactly what it is, dark matter particles will likely either annihilate themselves as they collide with each other ...
	2018-08-15: Quantum Theory's Most Incredible Prediction 09:50: ... with the EM field, with crazy networks of virtual particles and virtual matter, anti-matter loops between the real ingoing and outgoing ...
	2018-07-25: Reversing Entropy with Maxwell's Demon 09:26: ... universe must increase, and yet knowing the microstate of a system, no matter how thermodynamically mixed, allows you to decrease its ...
	2018-07-11: Quantum Invariance & The Origin of The Standard Model 01:35: ... it doesn't matter what we define to be altitude zero-- the bottom of the hill, sea level, ... 08:12: And now we know how it interacts with particles of matter to give them this symmetry.
	2018-07-04: Will A New Neutrino Change The Standard Model? 00:43: They are so weakly interacting that they pass through matter like it is isn't there. 01:09: ... family since the Higgs boson, sterile neutrinos are a candidate for dark matter, and their existence would have had a huge influence on the expansion of ... 01:22: ... between a neutrino and an atomic nucleus in some huge volume of matter, an entire glacier in the IceCube experiment or a huge vat of oil in the ... 01:38: Those regular neutrinos are spotted when they interact with matter via the weak nuclear force. 02:25: ... which carry the fundamental forces and the fermions which comprise matter. ... 09:25: That's heavier than regular neutrinos but way too light to be a candidate for dark matter. 04:39: And that's on top of the matter-antimatter split.
	2018-06-27: How Asteroid Mining Will Save Earth 09:04: It could be a simple matter of scooping up rocky material from the surface.
	2018-06-20: The Black Hole Information Paradox 00:34: But matter and energy aren't erased from existence. 14:49: ... interior or just the persistence of the field at the event horizon is a matter of ...
	2018-06-13: What Survives Inside A Black Hole? 00:40: Nothing can travel faster than light, and so nothing can escape from below the event horizon-- not matter, not light, not even information. 01:00: ... fact, every black hole in the universe, no matter how it formed or what happened to it afterwards, can be perfectly ... 05:09: The distribution of matter inside that surface is irrelevant. 09:59: If matter with these properties falls into a black hole, information about those properties is lost to the outside universe. 05:09: The distribution of matter inside that surface is irrelevant.
	2018-05-16: Noether's Theorem and The Symmetries of Reality 03:57: It doesn't matter when the collision happens, the results are the same.
	2018-05-09: How Gaia Changed Astronomy Forever 06:59: This dynamical information will be a powerful tool in understanding the dark matter distribution of the galaxy. 07:17: It's been hypothesized that disruptions in these flows are due to clumps of dark matter, so-called sub halos. 07:25: The nature of sub halos, and other details of dark matter's distribution, could help us figure out what dark matter really is. 06:59: This dynamical information will be a powerful tool in understanding the dark matter distribution of the galaxy. 07:17: It's been hypothesized that disruptions in these flows are due to clumps of dark matter, so-called sub halos. 07:25: The nature of sub halos, and other details of dark matter's distribution, could help us figure out what dark matter really is.
	2018-05-02: The Star at the End of Time 09:24: Joshua Hillerup asks whether dynamical friction leads to less dark matter near the centers of galaxies since dark matter's not very dense. 09:34: Yeah, dark matter is expected to be more evenly spread through the galaxy than things like stars and black holes. 09:41: ... matter exists in a puffy sphere some 200,000 light years in radius surrounding ... 09:24: Joshua Hillerup asks whether dynamical friction leads to less dark matter near the centers of galaxies since dark matter's not very dense.
	2018-04-25: Black Hole Swarms 10:18: You need a phenomenal amount of matter spread over a vast region. 11:00: We now know that they can lose energy to matter, but you would need a lot of matter. 10:18: You need a phenomenal amount of matter spread over a vast region.
	2018-04-18: Using Stars to See Gravitational Waves 07:21: ... gravitational waves should be able to dump some of their energy into matter, for example, into ...
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 01:24: ... like thermal energy being concentrated in your cup of coffee or all the matter in the observable universe being crunched into an infinitely dense point ... 08:20: ... consume high-energy density packets of matter called food and convert it to lower energy density waste as well as that ...
	2018-03-28: The Andromeda-Milky Way Collision 05:06: They used simulations of the gravitational interactions of millions of particles representing groups of stars and dark matter. 10:00: Patrick Hogan points out that it's more accurate not to think about dark matter as a thing. 10:06: ... the gravitational response of the universe doesn't match the visible matter given our understanding of that matter and/or the laws of ... 10:17: That's very fair, Patrick, but I would say that the evidence is converging on dark matter being some sort of particle or at least a stuff. 10:25: ... one thing, there's the consistency of the dark matter mass measurements of galaxies and galaxy clusters from gravitational ... 10:33: ... also the fact that dark matter appears to distribute itself differently to regular matter but still ... 10:43: ... the case of the result we discussed, the entire hypothesis that dark matter was responsible for the cooling of the early universe relies on it being ... 10:06: ... doesn't match the visible matter given our understanding of that matter and/or the laws of ... 10:33: ... also the fact that dark matter appears to distribute itself differently to regular matter but still comes ... 10:25: ... one thing, there's the consistency of the dark matter mass measurements of galaxies and galaxy clusters from gravitational lensing ...
	2018-03-21: Scientists Have Detected the First Stars 00:00: [MUSIC PLAYING] What do the first stars in the universe, dark matter, and superior siege engines have in common? 00:43: The same result also hints at brand new physics that may help us explain the nature of dark matter. 05:15: The only thing colder than this ambient hydrogen at the time, was dark matter. 05:20: So maybe, the hydrogen lost some of its heat to dark matter. 05:24: Yet, in order for that to happen, hydrogen would actually need to interact with the dark matter, and that's the whole thing about dark matter. 05:30: It doesn't interact with regular matter, except through gravity.
	2018-03-15: Hawking Radiation 00:12: He inspired all of us to pursue our curiosity, no matter the obstacles. 01:54: ... pairs of virtual particles, matter and antimatter, spontaneously appear and then annihilate each other, ... 03:51: ... modes, which you can crudely think of as a balance between virtual matter and antimatter ... 09:52: ... the narrative of Hawking's calculation as the splitting of entangled matter and antimatter pairs, even if it really is just a heuristic ... 08:40: So the split matter/antimatter a part of the picture is reasonable.
	2018-03-07: Should Space be Privatized? 08:56: Although, I'm actually not sure we'll have much choice in the matter.
	2018-02-28: The Trebuchet Challenge 01:25: More, it doesn't actually matter what path the object takes between two points under the influence of that force.
	2018-02-14: What is Energy? 04:38: And actually, it doesn't even matter if it takes one path out and a different path back. 04:53: ... experience the same conversion between potential and kinetic energy, no matter what path it ...
	2018-01-31: Kronos: Devourer Of Worlds 01:49: ... holes and neutron stars, as well as the distribution of gas and dark matter. ...
	2018-01-24: The End of the Habitable Zone 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. 11:56: If the event horizon swallows one half of a virtual matter anti-matter pair, then how does the black hole lose mass?
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 06:28: In planet formation models, lots of chunks of matter, and even some planets, get ejected from the relatively violent protoplanetary disk. 10:42: In the case of matter, uncertainty in momentum can manifest in both velocity and mass.
	2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series 00:58: ... is emergent from an underlying reality in which the particles that form matter arise from the combination of an infinity of possible ... 01:18: And forget matter. 06:43: See, momentum is sort of the generalization of frequency for what we call a matter wave. 06:58: ... generalizes the relationship between frequency and momentum of a matter ... 07:08: ... now call matter waves wave functions, and we can describe them in terms of position or ... 06:43: See, momentum is sort of the generalization of frequency for what we call a matter wave. 06:58: ... generalizes the relationship between frequency and momentum of a matter wave. ... 07:08: ... now call matter waves wave functions, and we can describe them in terms of position or ...
	2017-11-02: The Vacuum Catastrophe 02:33: Now, multiply a finite energy density no matter how small by infinity, and you get infinite energy density. 04:57: Einstein's theory tells us that any form of energy produces gravity, and what matters is the absolute amount of energy, not relative deviations. 09:16: ... baryon problem and some new observations that have found this missing matter in the vast filaments of the cosmic ... 09:33: ... for a time, it was thought that neutrinos might actually be dark matter until it was realized they just don't contain enough mass, nor are they ... 09:42: They're too hot to pull into the deep dark matter wells that we see in galaxy clusters. 09:54: However, usually the dark sector term is used to describe the actual sources of dark matter and dark energy. 10:07: A few of you asked how matter becomes or remains so hot in these gigantic filaments of the cosmic web. 09:42: They're too hot to pull into the deep dark matter wells that we see in galaxy clusters. 04:57: Einstein's theory tells us that any form of energy produces gravity, and what matters is the absolute amount of energy, not relative deviations.
	2017-10-25: The Missing Mass Mystery 00:00: [MUSIC PLAYING] For years, astronomers have been unable to find up to half of the matter in the universe. 00:49: However, we've known for some time that around 95% of the energy content of the universe is in dark matter and dark energy. 01:06: The remaining 5%, the light sector, represents all of the regular matter in the universe. 01:39: First, a quick refresher on dark matter and dark energy. 01:45: Dark matter is believed to be an invisible stuff that interacts only through gravity. 02:08: Now where dark matter pools, dark energy pushes. 02:25: The remaining 5% is regular baryonic matter. 02:35: But really, baryonic matter refers to atomic matter. 02:43: Baryonic matter interacts with light, so we can search for it by scanning the electromagnetic spectrum. 02:56: There's a huge discrepancy between the amount of baryonic matter our surveys find and the amount that our theories say should be out there. 04:07: And by analyzing these fluctuations, we can figure out the relative abundance of baryons to dark matter. 04:14: See, before the photons of the cosmic background radiation were released, they were trapped in the searing hot plasma of baryonic matter. 04:43: Those large blobs are driven by dark matter, which doesn't interact with light, so it can't produce density oscillations. 04:51: ... power spectrum, we can find the relative amount of baryonic versus dark matter. ... 05:02: Again, we calculate that they should be way more baryonic matter than we see in galaxies. 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them. 05:37: In the nexuses between filaments matter is dense enough for galaxies to form. 05:50: And yet, when we add up the mass from those galaxies, most of the baryonic matter predicted by a theory is missing. 09:10: ... pairs of nearby massive galaxies, the type typically found in giant dark matter ... 10:10: ... our predictions for the relative mass in baryons versus dark matter was so wrong, then it would mean the our understanding of the physics of ... 10:22: ... it seems that most of the regular matter in our universe is spread out in the vastness of intergalactic space, ... 11:39: And rather differently to regular matter, vacuum energy doesn't dilute in an expanding universe. 11:59: ... Zambelli asked whether the annihilation of virtual matter anti-matter particles would introduce energy into the universe and ... 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them. 09:10: ... pairs of nearby massive galaxies, the type typically found in giant dark matter halos. ... 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them. 02:43: Baryonic matter interacts with light, so we can search for it by scanning the electromagnetic spectrum. 02:08: Now where dark matter pools, dark energy pushes. 05:50: And yet, when we add up the mass from those galaxies, most of the baryonic matter predicted by a theory is missing. 02:35: But really, baryonic matter refers to atomic matter. 11:39: And rather differently to regular matter, vacuum energy doesn't dilute in an expanding universe.
	2017-10-19: The Nature of Nothing 01:42: But hypothetically, what would perfectly empty space look like, far from the nearest particle of matter or radiation? 15:36: HK Norman would like us to do a mention of the recent discovery of half of the missing matter in the universe.
	2017-10-11: Absolute Cold 01:06: Doing so has revealed some bizarre quantum states of matter. 01:24: We're all familiar with the states of matter-- solid, liquid, gas. 01:45: In these states of matter, particles have an enormous range of individual energies, some moving or vibrating fast, some slow. 02:34: The influence of the quantum world becomes far more apparent in the strange states of matter that exist at the cold end of the heat spectrum. 06:00: For a group of particles that make up any form of matter, that zero-point energy isn't actually zero. 06:46: To understand the universe, we need to understand how it behaves absent heat, absent light, and absent matter. 01:45: In these states of matter, particles have an enormous range of individual energies, some moving or vibrating fast, some slow. 01:24: We're all familiar with the states of matter-- solid, liquid, gas.
	2017-10-04: When Quasars Collide STJC 06:21: ... right down near the black hole where the jet begins, we think the matter should be so dense that the lowest energy radio waves have trouble ...
	2017-09-28: Are the Fundamental Constants Changing? 06:37: Remember quasars, insanely luminous maelstrom drums of superheated matter surrounding the most massive black holes in the universe?
	2017-09-20: The Future of Space Telescopes 10:38: Your contributions, no matter how small, really help keep the show running.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 12:40: There was the small matter of an eclipse to be witnessed.
	2017-08-16: Extraterrestrial Superstorms 12:25: Keith Gaughan wonders if the imbalance between matter and anti-matter is due to the time in the history of the universe that we're observing. 12:31: Well, actually, the fun thing about the one electron proposition is that it doesn't matter when in time you are. 12:37: You should always see the same proportion of matter to anti-matter. 13:06: It doesn't matter what times you choose.
	2017-08-10: The One-Electron Universe 01:29: However, Richard Feynman did take at least one aspect very seriously-- the mathematical equivalence of anti-matter as time-reversed matter. 06:05: CP transformations alone turn matter into mirror-reflected anti-matter. 06:16: In the sense of these fundamental symmetries, anti-matter is time-reversed matter. 06:22: ... already saw how expressing anti-matter as time-reversed matter is extremely useful in simplifying quantum field theory calculations, ... 12:24: M. Paulson poked fun at astronomers for using "dark" to describe anything they don't understand-- dark matter, dark energy, dark flow. 12:35: To be fair, we did workshop lots of other words, but huh matter, discombobulating energy, and WTF flow just didn't do as well in the focus group. 12:24: M. Paulson poked fun at astronomers for using "dark" to describe anything they don't understand-- dark matter, dark energy, dark flow. 12:35: To be fair, we did workshop lots of other words, but huh matter, discombobulating energy, and WTF flow just didn't do as well in the focus group.
	2017-08-02: Dark Flow 00:08: It may be that much of the matter in the cosmos is drifting due to the ancient gravitational pull of something outside the observable universe. 01:27: The laws of physics work the same no matter your speed. 05:38: It's like a lot of the matter in the universe is flowing toward some point beyond the edge of our universe. 06:02: When you look at scales larger than around a billion light years, you have basically the same amount of matter everywhere. 06:14: Matter shouldn't be more stretched out in any particular direction. 08:58: ... of observable universe with more galaxies, more clusters, more dark matter? ... 06:14: Matter shouldn't be more stretched out in any particular direction.
	2017-07-26: The Secrets of Feynman Diagrams 02:28: We'll soon see the power of representing anti-matter as time-reversed matter. 08:16: ... example, for two electrons exchanging a single photon, it doesn't matter if we draw the photon going from the first to the second or the second ... 10:14: Now, the interpretation of anti-matter as time-reversed matter is one that some, including Richard Feynman, took quite seriously.
	2017-07-19: The Real Star Wars 07:53: ... its damage by hitting things with fast-moving, non-explosive chunks of matter Brilliant Pebbles propose an orbiting weapons platform that delivered ...
	2017-07-12: Solving the Impossible in Quantum Field Theory 11:08: ... describe everything from particle scattering, self-energy interactions, matter-anti-media creation and annihilation, to all sorts of decay ...
	2017-07-07: Feynman's Infinite Quantum Paths 11:28: In part, by describing antimatter as regular matter traveling backwards in time. 13:59: No matter what speed you're traveling, it's as though the field is stationary with respect to you. 14:06: ... points out that if matter and antimatter particles are always created in pairs, shouldn't there be ... 14:27: Almost all of the matter and antimatter annihilated each other, leaving only one in a billion particles of matter. 14:34: This tiny imbalance of matter over antimatter is a deep mystery. 14:44: This so-called charge parity or CP violation has been seen in experiments, implying that the universe does treat antimatter differently to matter. 11:28: In part, by describing antimatter as regular matter traveling backwards in time. 14:16: Up to around a millionth of a second after the Big Bang, the universe was hot enough for photons to be continuously forming matter-antimatter pairs.
	2017-06-28: The First Quantum Field Theory 05:31: However, understanding the behavior of light and its interaction with matter required a different approach. 08:43: And there's another reason this second quantization is better at describing the interactions of light and matter. 09:29: The resulting quantum electrodynamics describes the interactions of matter and radiation with stunning success. 05:31: However, understanding the behavior of light and its interaction with matter required a different approach.
	2017-06-21: Anti-Matter and Quantum Relativity 00:56: And Louis de Broglie had shown that all matter has this dual wave-particle nature. 01:21: ... describes how these matter waves, represented as wave functions, change over time, and allowed ... 09:34: Well, it's a vibration in the same quantum field as its regular matter counterpart. 10:41: When matter, anti-matter counterparts find each other, they annihilate, releasing an awful lot of very real energy. 09:34: Well, it's a vibration in the same quantum field as its regular matter counterpart. 01:21: ... describes how these matter waves, represented as wave functions, change over time, and allowed physicists ...
	2017-06-07: Supervoids vs Colliding Universes! 07:47: It's the same notion that people have tried to use to explain dark matter. 08:01: However, modified gravity is on shaky ground because, well, dark matter is looking more and more like real stuff, not incorrect gravity. 04:05: A photon entering a matter-rich galaxy cluster gets an energy boost as it falls into the cluster's gravitational well.
	2017-04-19: The Oh My God Particle 11:39: Don't you hate it when knowing something doesn't translate to remembering you know it when it really matters?
	2017-03-22: Superluminal Time Travel + Time Warp Challenge Answer 10:15: Our experience of the universe is a thing that emerges from the forward causal evolution of the matter that we're composed of.
	2017-03-15: Time Crystals! 01:09: He suggested a type of matter that exhibits a sort of fundamental oscillation over time. 02:16: Normal matter that is in what we call thermal equilibrium only has random internal motion. 02:21: In solid matter, that would be the vibrational buzz of its constituent atoms. 02:29: In regular matter in equilibrium, statistical properties stay the same over time. 02:34: ... because there are global statistical differences in the state of the matter, non-random patterns that change over ... 05:43: This is sort of like the phase diagram of regular matter in which you plot pressure versus temperature. 06:08: ... then the time crystal effectively melts into regular time symmetric matter, in which the ion chain follows the rhythm of the driving signal ... 09:29: ... that we've seen matter settle into discrete lattices in time just like in regular crystals, ... 10:07: ... Nature of Matter by Professor David Ball may not cover time crystals, but it does go into ... 02:34: ... because there are global statistical differences in the state of the matter, non-random patterns that change over ... 09:29: ... that we've seen matter settle into discrete lattices in time just like in regular crystals, perhaps ...
	2017-03-08: The Race to a Habitable Exoplanet - Time Warp Challenge 01:11: It lets us figure out what spacetime looks like for every observer, no matter what his or her velocity is.
	2017-02-15: Telescopes of Tomorrow 02:55: Webb will help us learn whether stars form galaxies or galaxies form stars and the role of dark matter in the whole process.
	2017-02-02: The Geometry of Causality 06:34: Moving between these reference frames is now a simple matter of squaring up our traveler's axes. 07:27: They will always land on the same hyperbola, no matter the observer's reference frame.
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 00:50: ... Matter falling into the extreme gravitational well of a black hole will reach ...
	2016-12-21: Have They Seen Us? 15:16: Its matter became part of the black hole and re-emerges as that Hawking radiation.
	2016-12-14: Escape The Kugelblitz Challenge 04:17: It doesn't matter why.
	2016-12-08: What Happens at the Event Horizon? 09:24: ... meet it, but it will always appear to be just a little further ahead no matter how close to that horizon we dare to ... 18:08: ... double solution theory in which the so-called particle was actually a matter wave itself embedded in and carried by the sine wave, represented by the ...
	2016-11-30: Pilot Wave Theory and Quantum Realism 02:59: This required an almost mystical duality between the wave and particle-like nature of matter. 03:25: ... from Louis de Broglie, the guy who originally proposed the idea that matter could be described as waves right at the beginning of the quantum ... 12:59: Burak asks why quark/strange matter isn't found naturally in the universe given that it's supposed to be so stable. 13:07: OK, so the hypothesis is that strange matter is the most stable matter in the universe. 13:45: And the problem is that the universe at this time wasn't dense enough and was expanding too quickly for strange matter to form in any great abundance. 13:55: That said, some strange matter made have formed during the quark epoch. 14:07: ... on the as-yet-unknown physics of strange matter, these strangelets may even be expected to be more stable the larger they ... 14:18: In fact, such strangelets may even convert any regular matter they come into contact to into strange matter. 12:59: Burak asks why quark/strange matter isn't found naturally in the universe given that it's supposed to be so stable.
	2016-11-16: Strange Stars 03:12: Neutronium is degenerate matter, and I don't mean that in the same way that your parents probably used the word. 03:19: Degenerate matter is so compressed that particles can't get any closer together without occupying the same quantum states. 04:00: This so-called quark matter is its very own type of bizarre. 04:05: ... think that a type of gas-like quark matter, a so-called quark-gluon plasma, filled the entire universe until around ... 04:38: ... the quark matter in a neutron star is forged by insane pressures, not by the ... 04:59: We sometimes call a neutron star with such a quark matter core a quark star. 05:10: Quark matter made of these quark types would need to be confined by incredible pressures to maintain stability outside the atomic nucleus. 05:19: So that probably rules out having an entire star made of this stuff, unless the quark matter is also strange. 05:36: The result is strange matter. 05:38: It's a special type of quark matter. 05:58: ... lower energy state means that strange matter may be the most stable form of matter in the universe, more stable even ... 08:23: A possible explanation is that a quark matter core formed at the heart of this neutron star and is slowly transforming into strange matter. 08:48: Some appear a little bit too small for their mass, suggesting quark matter densities. 12:57: ... entropic gravity, and the possibility that it might explain both dark matter and dark ... 04:59: We sometimes call a neutron star with such a quark matter core a quark star. 08:23: A possible explanation is that a quark matter core formed at the heart of this neutron star and is slowly transforming into strange matter. 08:48: Some appear a little bit too small for their mass, suggesting quark matter densities.
	2016-11-09: Did Dark Energy Just Disappear? 00:52: They expected to see that this expansion rate was slowing down due to the gravitational effect of all of the matter in the universe. 06:35: ... just the gravitational effect of regular energy, and that's mostly dark matter, but also stars, planets, gas, radiation, et ... 07:00: This graph is how we like to show the balance of these energy types: dark energy on the Y-axis, and normal energy (so, matter) on the X. 07:28: Those blue ovals represent the ranges of combinations of matter and dark energy that are consistent with the new supernova measurements. 08:19: Except that bottom-left corner of the graph also represents a universe that has almost no matter in it either. 08:32: But our universe definitely has matter in it. We even have a pretty good idea how much. 08:38: Counting galaxies and weighing dark matter tells us that Omega-m is probably around 0.3, but it's at least around 0.2. 10:24: That little region where the supernova and CMB results overlap represents the most likely combination of dark energy and matter. 11:03: ... has to be something out there countering the gravitational effect of matter and flattening the geometry of ... 11:47: No matter how well-accepted a result is, everything we think we know is always subject to being questioned and retested. 08:38: Counting galaxies and weighing dark matter tells us that Omega-m is probably around 0.3, but it's at least around 0.2.
	2016-10-19: The First Humans on Mars 01:56: Whether 10 years is remotely feasible is another matter. 09:29: Even a black hole made entirely from light, a kugelblitz, is the same thing as a black hole formed from regular matter.
	2016-10-12: Black Holes from the Dawn of Time 00:03: In the very first instant after the Big Bang, the density of matter was so great everywhere that vast numbers of black holes may have formed. 01:11: So why didn't all the matter in the universe become black holes then? 01:43: Now, matter in the early universe was pretty smoothly spread out, and the universe was expanding fast. 02:06: It reveals tiny differences in the density of matter from one point in space to the next. 04:43: Could primordial black holes be dark matter? 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. 07:07: ... that PBHs are actually very rare, and that they're certainly not dark matter. ... 07:24: ... have already evaporated due to Hawking radiation definitely are not dark matter, and that rules out any PBHs lighter than about a billion ... 08:54: It's a different matter if one hit the Earth.
	2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate 05:04: Measurement of the spin of one of these particles tells us the spin of the other, no matter how large the distance between them.
	2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer 03:05: By that, I mean dark to electromagnetism and generally interacting with regular matter very little. 03:25: ... could be everywhere and we wouldn't know it, like ninjas and like dark matter. ... 03:40: Not that dark matter is ninjas. 03:46: I mean that this new particle may have something to do with dark matter.
	2016-08-24: Should We Build a Dyson Sphere? 01:55: ... large quantities, much more than there is non-hydrogen or helium matter in all of the planets in the solar ... 06:14: What we then do with that energy is another matter. 07:43: ... we could perhaps sustain it from evaporation by feeding it with new matter. ... 07:54: ... conversion of mass into energy, assuming we can find a way to pump new matter into the proton-sized Kugelblitz against the tide of Hawking ...
	2016-08-10: How the Quantum Eraser Rewrites the Past 02:06: Or a houseplant, for that matter.
	2016-07-27: The Quantum Experiment that Broke Reality 10:54: It's a thorough review of a very complicated subject matter.
	2016-06-29: Nuclear Physics Challenge 00:19: But here's TL;DR. Particles of matter have wave-like properties. 00:24: These matter waves don't have perfectly-defined positions, but rather, occupy a range of possible positions.
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 13:22: ... for a given lens, there could be a range of different configurations of matter that produce the same distribution of light seen in the lens, so image ...
	2016-06-15: The Strange Universe of Gravitational Lensing 04:31: And we've confirmed that the vast majority of mass in this universe is in the form of dark matter. 05:33: The quasar is a vortex of superheated matter falling into a black hole. 07:06: We see that they encircle the vast strands and nexuses of dark matter that form the cosmic web, allowing us to understand its structure. 05:33: The quasar is a vortex of superheated matter falling into a black hole.
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 00:18: ... our entire current understanding of the building blocks of all matter. ... 03:09: The broad family of possibilities include one-- dark matter. 03:14: There are theoretical ideas of particles that could cause a bump at this energy, and would also make pretty decent dark matter candidates. 07:31: But once initiated, it doesn't really matter whether the CO2 increased first, or the temperature increased first. 09:12: And how many times it would double in size in the future before matter no longer has any significant influence on expansion. 09:55: So 70 parts dark energy and 30 parts matter. 10:02: Back in the day, it was whatever the sum of dark energy and matter was back then. 10:08: The overall amount of energy in the form of matter doesn't change, because matter is spreading out with the expanding volume. 10:16: Matter past equals matter now for a co-moving volume. 11:05: ... in our current 70 units of dark energy and 30 units of matter, and we get that the universe was 36% of its current size when dark ... 11:27: You can take exactly the same approach to ask when in the future matter will only have a 10% contribution to the energy in that volume. 11:44: Add these two numbers together, and you get that matter and dark energy both produce a significant effect for around two doublings. 13:08: Is there something about the tipping point between the dominance of matter versus dark energy that makes the universe more hospitable for life? 03:14: There are theoretical ideas of particles that could cause a bump at this energy, and would also make pretty decent dark matter candidates. 10:08: The overall amount of energy in the form of matter doesn't change, because matter is spreading out with the expanding volume. 13:08: Is there something about the tipping point between the dominance of matter versus dark energy that makes the universe more hospitable for life?
	2016-06-01: Is Quantum Tunneling Faster than Light? 01:30: French mathematician and physicist Louis de Broglie figured out that any material object is really a matter wave.
	2016-05-25: Is an Ice Age Coming? 12:55: So to summarize, as the universe expands, the energy in matter in any one co-moving volume or expanding volume is conserved. 13:28: ... contribution to the modern universe-- far less, even, than baryonic matter, which itself is far less than dark ...
	2016-05-18: Anti-gravity and the True Nature of Dark Energy 00:42: There's it's just too little matter in it to recollapse. 03:48: The more matter and energy in the universe, the harder gravity pulls inwards, trying to stop the expansion or speed up the collapse. 05:25: See, high pressure from regular matter and energy means very fast-moving particles. 06:47: The cosmological constant was designed to work in the opposite direction to regular matter and energy. 07:17: ... our far future universe, regular matter will have diluted away and will only have the density and pressure due ... 07:27: Now, the energy density of dark energy is positive, just like regular matter. 07:33: It has to be, because dark energy helps regular matter flatten the geometry of the universe. 07:39: That means its density term also works on the side of matter to try to slow down the universe in the regular attractive gravity way. 07:33: It has to be, because dark energy helps regular matter flatten the geometry of the universe.
	2016-05-11: The Cosmic Conspiracy of Dark Energy Challenge Question 00:36: The balance between dark energy and matter in the modern universe is on the side of dark energy. 00:42: ... billions of years now, ever since it became large enough for regular matter to dilute away enough so that dark energy ... 01:05: If you add up the energy in any large volume of space, about 70% of it is dark energy and the remaining 30% is in the form of regular matter. 01:15: And by regular, I also mean dark matter, which is actually most of that 30%. 01:36: Say a cubic million light years, around 70% dark energy, 30% matter. 02:47: At the same time, the total amount of regular matter in any expanding region remains constant. 02:55: That means the density of matter decreases as the universe expands. 02:59: At some point in the past, there was a perfect balance between dark energy and matter. 03:14: A given giant box in the universe currently has around 30 parts matter and around 70 parts dark energy. 03:22: Halve its volume, and it still has those 30 parts matter, but only around 35 parts dark energy. 05:01: And for the vast majority of future doublings, regular matter will have diluted away and be an infinitesimal influence compared to dark energy. 05:29: ... for how many of those infinite future doublings will regular matter and energy have any significant effect-- again, at least 10% of the ... 05:43: ... effect and how many billion years in the future will it take for matter to cease to ... 02:55: That means the density of matter decreases as the universe expands.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 09:06: But if dark energy diluted away, like regular matter does, that effect would diminish as the universe expanded. 10:15: But if the density of dark matter varies with time, then there are a range of possibilities. 10:40: So dark energy only has an observable effect when its density is at least comparable to the density of regular matter. 10:49: The density of matter inside galaxies is much, much higher than in between galaxies and even much, much higher than the average for the universe. 10:15: But if the density of dark matter varies with time, then there are a range of possibilities.
	2016-04-27: What Does Dark Energy Really Do? 00:03: The idea that the fate of our universe is governed by forces that we can see was abandoned with the discovery of dark matter. 05:23: And so a lower density of matter would be needed to explain how the universe slowed down to the current rate of expansion. 05:32: ... universe has always been expanding at the rate we see now, so almost no matter slowing the universe ... 06:32: Or conversely, the supernovae were fainter than you'd expect, even for a universe that has no matter in it at all. 09:04: Currently, there's still enough matter in the universe to influence the expansion rate, but we're already at the point where dark energy dominates. 11:16: However, they do sample a large enough fraction of it to tell us that matter in the universe is pretty smoothly distributed. 11:23: These surveys don't measure dark matter content of all of their galaxy clusters. 11:28: But again, we've weighed up the dark matter in enough of them to be able to extrapolate. 11:23: These surveys don't measure dark matter content of all of their galaxy clusters. 05:32: ... universe has always been expanding at the rate we see now, so almost no matter slowing the universe ...
	2016-04-20: Why the Universe Needs Dark Energy 01:26: ... weighing up all of the matter in the universe, astronomers have figured out that there just isn't ... 02:46: Spacetime will be curved, no matter what. 07:38: As the universe expands, regular matter and energy get diluted away. 08:04: ... the universe gets large enough, the density of regular matter will, at some point, drop below that of this vacuum energy, as described ... 09:43: Within these regions, the shape of spacetime is dominated by the gravitational field of the densely packed matter. 10:20: Mychelly Goulart would like to know whether the density we use in the Friedmann equation includes dark matter. 10:28: ... calculate when we figured out the fate of the universe does include dark matter, which we can measure by its gravitational effect in several independent ... 10:38: Even with dark matter, the universe is just not dense enough to recollapse.
	2016-04-13: Will the Universe Expand Forever? 02:16: ... Archibald Wheeler put it more simply-- "Spacetime tells matter how to move, while matter tells spacetime how to curve." Now, before we ... 07:36: Astronomers worked for decades to weigh up the galaxies across vast swaths of the universe, including their dark matter. 08:50: After all, matter tells spacetime how to curve. 02:16: ... Wheeler put it more simply-- "Spacetime tells matter how to move, while matter tells spacetime how to curve." Now, before we do any general relativity, let's ... 08:50: After all, matter tells spacetime how to curve. 02:16: ... Wheeler put it more simply-- "Spacetime tells matter how to move, while matter tells spacetime how to curve." Now, before we do any general relativity, let's develop ... 08:50: After all, matter tells spacetime how to curve.
	2016-04-06: We Are Star Stuff 00:39: ... the building blocks of matter, the elementary fields that fill our universe, and the particles that ... 09:45: ... as gravitational radiation, but also as a blast of newly formed heavy matter, including something like 10% of the Earth's mass in ...
	2016-03-23: How Cosmic Inflation Flattened the Universe 10:15: ... Schneider asks, "Why does dark matter in a galaxy seem to form a sphere?" Well, this is because dark matter ... 10:47: Dark matter doesn't sweep itself. 10:54: So the orbits of any bit of dark matter can be in any orientation or direction. 10:15: ... matter in a galaxy seem to form a sphere?" Well, this is because dark matter doesn't really interact with itself except ... 10:47: Dark matter doesn't sweep itself.
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 07:31: The Earth and the Sun, for that matter, rotate on their axes.
	2016-03-02: What’s Wrong With the Big Bang Theory? 03:52: But we can't confidently describe this stuff that the universe contained, the weird state of matter that far back. 09:55: ElectroMechaCat asks why if the universe is expanding, doesn't matter also get stretched with that expansion. 10:06: ... surprising the matter would not be stretched by expansion because the bonds between and within ... 10:25: ... metric, which describes a space time in which all matter is perfectly smoothly ...
	2016-02-24: Why the Big Bang Definitely Happened 06:29: ... then those ripples should have been frozen into the distribution of matter at the moment the CMB was created, and those ripples should still be ...
	2016-02-03: Will Mars or Venus Kill You First? 08:31: So we'll be around for many more episodes of "Space Time." In the last episode, we finished our series on the origin of matter and time.
	2016-01-27: The Origin of Matter and Time 00:16: In this episode, we're going to rebuild our understanding and explore the origin of matter and time. 01:05: Today, we're going to bring together these ideas to explore what matter, time, and things really are. 06:17: ... already covered the fact that real matter is comprised of massless light speed components confined not by mirrored ... 08:50: ... this picture, time and mass and matter become emergent properties of the causal propagation of patterns of ... 01:05: Today, we're going to bring together these ideas to explore what matter, time, and things really are.
	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. 00:09: ... today we're going to go even deeper and explore the connection between matter, motion, and the nature of ... 01:03: Any clock is just an arrangement of matter. 02:22: The familiar smooth flow of time only emerges as these particles are bundled into what we think of as matter. 05:39: So what does this odd example of the photon clock have to do with real time and real matter? 07:14: So the confinement of light speed particles gives matter mass. 07:19: In fact, this confinement, this bundling of energetic moving parts, is what makes it matter. 07:24: But now it looks like this same bundling of light speed particles can also given matter time. 07:38: But what is it about not traveling at the speed of light that allows matter to have structure and to change? 07:44: What prohibits matter from reaching the speed of light? 07:55: In the last episode, we talked about the true nature of matter and mass. 00:02: In the last episode, we saw how matter fills mass because of the energy of its internal moving parts. 07:14: So the confinement of light speed particles gives matter mass. 00:09: ... today we're going to go even deeper and explore the connection between matter, motion, and the nature of ... 07:24: But now it looks like this same bundling of light speed particles can also given matter time.
	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? 00:40: The answer to this will take us to a much deeper question-- what is the origin of matter and time? 00:49: So today, we're going to look at the true nature of matter and mass a little more closely. 08:18: ... explore these questions when we delve deeper into the mystery of matter and time in the next episode of "Space Time." In the last episode of ... 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?
	2015-12-16: The Higgs Mechanism Explained 07:33: ... now, we'll be delving deeper to the mysteries of matter and time in the next episode of "Space Time." In the last episode, we ...
	2015-12-09: How to Build a Black Hole 03:09: And it defines the volume that can be occupied by the strange matter in a neutron star. 03:15: ... the exact way that the matter of a neutron star fills this 6D quantum phase space depends on two ... 03:41: And by thing, I mean fermion, the particle type comprising all regular matter. 04:02: Now, this rule is what keeps electrons in their separate stable orbits and, in turn, is part of what allows solid matter to have its structure. 04:26: This weird state of matter where phase space is completely full-- we call it degenerate matter. 04:51: See, it's not a matter of force. 05:17: The details may be a topic for another episode, but in short, quantum mechanics describes matter as a distribution of possibilities. 06:23: So a neutron star is comprised of the densest matter in the universe. 07:06: If we can somehow add more matter to a neutron star-- throw another star at it, maybe-- it won't get spatially larger. 07:14: The extra matter certainly needs somewhere to go. 07:27: The more matter of the neutron star, the smaller its radius. 07:47: And the densities inside the star produce some very strange states of matter.
	2015-11-25: 100 Years of Relativity + Challenge Winners! 00:36: ... Time." General relativity's profound description of space and time, of matter and energy, emerged from the simplest of thought experiments, simple ... 01:24: On December 9, we'll delve deeper than ever into the weirdness of black holes, after which we'll start exploring the nature of matter and time. 04:33: ... also the shape and composition of Apophis doesn't matter at all for this part of the calculation, which is a big part of the ...
	2015-11-18: 5 Ways to Stop a Killer Asteroid 01:14: It's really not a matter of if, just of when. 04:09: And speaking of Armageddon, what do we do if we spot an incoming city killer, or for that matter, a planet killer that we somehow missed?
	2015-11-05: Why Haven't We Found Alien Life? 01:54: In a way, it doesn't matter how improbable sentience is. 10:55: ... the walls in any direction besides forwards and our negative mass matter may also end up on the ...
	2015-10-28: Is The Alcubierre Warp Drive Possible? 01:51: ... towards the central singularity faster than light, carrying light, matter, monkeys, and everything else with ... 03:05: ... solve the Einstein equations backwards to figure out what arrangement of matter and energy would be needed to create ... 03:49: ... 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 ... 05:58: If the bubble is small enough, then we may not even need actual exotic matter. 01:51: ... towards the central singularity faster than light, carrying light, matter, monkeys, and everything else with ...
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 04:50: When matter meets it's antimatter counterpart, both particles are annihilated, liberating most of the rest mass as energy.
	2015-10-07: The Speed of Light is NOT About Light 02:46: It would imply that space and time and matter don't exist. 06:07: It doesn't matter where the pony is, how fast it's going, or in what direction it's skating. 09:51: There is no matter. 02:46: It would imply that space and time and matter don't exist.
	2015-09-30: What Happens At The Edge Of The Universe? 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. 08:25: Shadowmax889 asks why stars and planets aren't filled with dark matter? 08:31: Dark matter is cold and clumpy, which means it can bunch together to form galaxies. 09:03: Dark matter doesn't do that. 09:16: ... informs us that upon winning a Nobel Prize for discovering dark matter particles, he or she would spend all of the prize money on Phoenix ... 09:03: Dark matter doesn't do that. 09:16: ... informs us that upon winning a Nobel Prize for discovering dark matter particles, he or she would spend all of the prize money on Phoenix ...
	2015-09-23: Does Dark Matter BREAK Physics? 00:00: [MUSIC PLAYING] Dark matter literally binds the galaxy together. 00:07: Nobody knows what dark matter is. 00:34: Either we're missing and frankly don't understand at least 80% of all the matter in the universe or our current understanding of gravity is wrong. 00:45: This is the mystery of dark matter. 00:47: ... before we get into figuring out exactly what dark matter is or isn't, I want to give you completely independent evidence for its ... 01:29: So knowing this, let's summarize the actual possibilities for dark matter. 01:41: Two, not so great, dark matter is a type of particle that's beyond our current understanding of particle physics. 02:12: If dark matter exists in this model, its mass probably needs to come from protons and neutrons. 02:19: ... this is dark matter, the galaxy would need to be swarming with baryonic things as massive as ... 03:03: But not nearly enough to account for all of the dark matter. 03:43: Could it be that what we see as dark matter just comes from gravity behaving differently on truly gigantic scales? 03:55: ... distance instead of distance squared, and then you don't even need dark matter. ... 04:21: Any replacement theory has to reproduce all, and I mean all, of the verified predictions of Einstein's theory and be able to explain dark matter. 04:39: They either need some serious fine-tuning or you have to add back in some actual dark matter particles, which kind of defeats the purpose. 05:02: So if dark matter really comes from weirdly behaving gravity, then the cluster's gravity should stay concentrated on the gas. 05:08: ... if dark matter is an unseen particle, and it's the type of particle we think it might ... 05:25: And we see that in the Bullet Cluster, the dark matter is with the stars. 05:29: This tells us that matter is a real particle, not just broken gravity. 05:35: Dark matter exists and it represents, if not broken, at least incomplete particle physics. 05:45: It has to be pretty slow moving, or cold, because we know that dark matter clumps together gravitationally to build galaxies and clusters. 06:10: There's no way there's enough regular matter to do that. 06:13: Dark matter, as well as binding the galaxy together, is also the main force in forming galaxies in the first place. 06:20: No dark matter, no galaxies. 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. 06:55: Some of them fit the bill for dark matter. 07:05: Some of which may actually exist and some of them may be dark matter. 07:14: ... the fall-out between the unthinkably rare collisions between a dark matter particle and an atomic ... 07:22: We also watch the heavens for the equally elusive gamma radiation produced when dark matter particles annihilate each other out in space. 07:36: ... I'll report any previously undiscovered dark matter particles on the next episode of "SpaceTime." Last time on "SpaceTime," ... 05:45: It has to be pretty slow moving, or cold, because we know that dark matter clumps together gravitationally to build galaxies and clusters. 02:12: If dark matter exists in this model, its mass probably needs to come from protons and neutrons. 05:35: Dark matter exists and it represents, if not broken, at least incomplete particle physics. 00:00: [MUSIC PLAYING] Dark matter literally binds the galaxy together. 07:14: ... the fall-out between the unthinkably rare collisions between a dark matter particle and an atomic ... 04:39: They either need some serious fine-tuning or you have to add back in some actual dark matter particles, which kind of defeats the purpose. 06:23: And even then, galaxies could only have formed if dark matter particles are cold, massive, and weakly interacting. 07:22: We also watch the heavens for the equally elusive gamma radiation produced when dark matter particles annihilate each other out in space. 07:36: ... I'll report any previously undiscovered dark matter particles on the next episode of "SpaceTime." Last time on "SpaceTime," we talked ... 07:22: We also watch the heavens for the equally elusive gamma radiation produced when dark matter particles annihilate each other out in space.
	2015-08-19: Do Events Inside Black Holes Happen? 07:43: Loosely speaking, it's like being in an episode of "The Twilight Zone," in which no matter which way you turn, you're always facing inwards. 09:52: So to external observers, most of the matter never crosses the horizon.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 03:58: Because if that were the case, then water in lakes should also be lifted and, for that matter, so should sand and rocks and you. 04:05: Remember, the object's mass doesn't matter.
	2015-07-02: Can a Circle Be a Straight Line? 07:57: You should watch as many videos about special relativity as you can no matter who's made them.
	2015-06-03: Is Gravity An Illusion? 01:25: ... constant velocity because that distinction is meaningless and simply a matter point of ...
	2015-05-27: Habitable Exoplanets Debunked! 08:23: There's some matter exchanged just because the human body is porous.
	2015-05-20: The Real Meaning of E=mc² 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. 07:26: OK, what about matter-antimatter annihilation?
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 09:44: I think that's a matter of semantic taste, but it certainly isn't what you think it is. 09:53: ... turn out to be event pairs for which a single piece of matter or light could have been present at both events, which corresponds to a ...
	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. 06:28: Answer-- once you're outside the gravitating object, what matters is mass.
	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.
	2015-03-25: Cosmic Microwave Background Explained 00:29: ... accounting for all possible types of interference, no matter how you orient your dish, there's this constant underlying microwave ...
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 07:58: Another possibility raise is that maybe there exists an exotic but more stable state of nuclear matter involving strange quarks. 08:04: And that, if some of that matter appeared on Earth, it would trigger a chain reaction wherein every nucleus on Earth would revert into that state. 09:13: ... take, not just to overcome the gravitational attraction between all the matter on Earth, but to split apart every interatomic bond as ... 08:04: And that, if some of that matter appeared on Earth, it would trigger a chain reaction wherein every nucleus on Earth would revert into that state. 07:58: Another possibility raise is that maybe there exists an exotic but more stable state of nuclear matter involving strange quarks.

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