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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 03:49: They can’t hold a rigid structure like solids can, rather they take on the shape of thxeir container. 14:17: But the supercritical layer is an integral part of the structure of the biggest planets in the solar system.
	2022-12-08: How Are Quasiparticles Different From Particles? 09:43: Add a voltage and those electrons are free to travel through the structure as an electrical current. 10:26: Which in turn means that coherent structures of phonons become possible.
	2022-10-19: The Equation That Explains (Nearly) Everything! 14:00: ... different particle masses, or chooses coupling strengths like the fine structure constant we discussed recently. And it doesn't explain dark energy or ...
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 07:45: ... - multiple controllable sail panels mounted along the narrow structure of the craft.   These sails would need to be made of ... 15:45: ... one were we talked about the mysterious   meaning of the fine structure constant. AJMansfield asks whether JWST also have a   program ... 18:29: ... the way the quantum fields behave - including raising the fine structure constant.   We routinely reach temperatures where ... 19:23: ... also be different during that time?   Well yes! The fine structure constant is defined as the electron charge squared divided by 4pi ... 15:45: ... one were we talked about the mysterious   meaning of the fine structure constant. AJMansfield asks whether JWST also have a   program for doing ... 18:29: ... We routinely reach temperatures where the fine structure constant changes in our   particle accelerators. After all, we ... 19:23: ... also be different during that time?   Well yes! The fine structure constant is defined as the electron charge squared divided by 4pi ... 15:45: ... one were we talked about the mysterious   meaning of the fine structure constant. AJMansfield asks whether JWST also have a   program for doing just, ... 18:29: ... the energies of the electroweak era, when the   fine structure constant isn’t even relevant. There aren’t many natural places in the ... 19:23: ... squared to vacuum permittivity. Remember   that the find structure constant represents the strength of electromagnetism, and the classical   ... 18:29: ... the way the quantum fields behave - including raising the fine structure constant.   We routinely reach temperatures where the fine structure constant ... 19:23: ... the Planck constant times the speed of light. If the fine structure constant   was different then one or more of these other constants would have ... 04:36: ... lensed by a second galaxy   much closer to us. The detailed structure  is scrambled. But this is what you get when   you try to ... 19:23: ... asks, If the fine structure constant wasn't constant (like during the big   bang), wouldn't the ... 20:21: ... Niles speculates that the fine structure constant was set when the 4D experimentalists   coding our universe ... 19:23: ... asks, If the fine structure constant wasn't constant (like during the big   bang), wouldn't the ... 20:21: ... Niles speculates that the fine structure constant was set when the 4D experimentalists   coding our universe ...
	2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics? 00:19: This is the fine structure constant, and it appears everywhere in our equations of quantum physics, and we’re still trying to figure out why. 00:30: ... fine structure constant, designated as the greek letter alpha, just looks like one of ... 00:57: ... my first question to the Devil will be: What is the meaning of the fine structure constant?” Even Richard Feyman pondered its mysteries his entire ... 03:45: This number just happens to be 1/137.035999, the fine structure constant. 03:54: ... this number only appeared in the formula  for the fine structure splitting of spectral lines it would be just a fun oddity, except this ... 04:34: And that’s just the tip of the iceberg for the appearances of the fine structure constant in the laws of physics. 04:50: ... and now more than 100 years after Sommerfeld  discovered the structure constant, I’d like to tell you what it ... 05:55: And that’s exactly what the  fine structure constant is:   it’s the coupling strength of the electromagnetic force. 06:23: So the Fine Structure Constant sets the  "strength" of the electromagnetic force. 06:37: So it’s starting to make sense why the fine structure constant appears in all of these formulas that depend on the electromagnetic force. 07:06: In fact the fine structure constant isn’t as constant as it sounds. 07:30: We’re now at the bottom of the energy scale,  and the fine structure constant has bottomed out at 1/137.035999. 08:33: ... ended up with this particular   value for the fine structure constant or many of the other fundamental ... 09:08: But the fact that the fine structure constant  has such a convenient value isn’t the weirdest thing about it. 10:10: But the fine structure constant is unitless. 10:27: That’s handy for interstellar communication, but it also tells us that’s something's -seriously- up with the fine structure constant. 10:52: But these things don’t pop up in all these unexpected places like the fine structure constant does. 11:50: But without any units, it's not immediately clear what kind of relationship the Fine Structure Constant represents. 12:08: If the other constants of nature tie various physical parameters together, perhaps the fine structure constant is what ties those constants together. 12:43: ... fact that this canceling gives the fine structure constant, and the fine structure constant also represents the ... 13:15: ... it could be that the fine structure constant is not a physical constant, but a mathematical one, like pi, ... 13:51: ... called the fine structure constant  “one of the greatest damn mysteries  of physics” and ... 14:13: And perhaps that number was 1/137, the fine  structure constant - whose value sets the rules of this particular space time. 00:19: This is the fine structure constant, and it appears everywhere in our equations of quantum physics, and we’re still trying to figure out why. 00:30: ... fine structure constant, designated as the greek letter alpha, just looks like one of the many ... 00:57: ... my first question to the Devil will be: What is the meaning of the fine structure constant?” Even Richard Feyman pondered its mysteries his entire ... 03:45: This number just happens to be 1/137.035999, the fine structure constant. 04:34: And that’s just the tip of the iceberg for the appearances of the fine structure constant in the laws of physics. 04:50: ... and now more than 100 years after Sommerfeld  discovered the structure constant, I’d like to tell you what it ... 05:55: And that’s exactly what the  fine structure constant is:   it’s the coupling strength of the electromagnetic force. 06:23: So the Fine Structure Constant sets the  "strength" of the electromagnetic force. 06:37: So it’s starting to make sense why the fine structure constant appears in all of these formulas that depend on the electromagnetic force. 07:06: In fact the fine structure constant isn’t as constant as it sounds. 07:30: We’re now at the bottom of the energy scale,  and the fine structure constant has bottomed out at 1/137.035999. 08:33: ... ended up with this particular   value for the fine structure constant or many of the other fundamental ... 10:10: But the fine structure constant is unitless. 10:27: That’s handy for interstellar communication, but it also tells us that’s something's -seriously- up with the fine structure constant. 10:52: But these things don’t pop up in all these unexpected places like the fine structure constant does. 11:50: But without any units, it's not immediately clear what kind of relationship the Fine Structure Constant represents. 12:08: If the other constants of nature tie various physical parameters together, perhaps the fine structure constant is what ties those constants together. 12:43: ... fact that this canceling gives the fine structure constant, and the fine structure constant also represents the relationship between ... 13:15: ... it could be that the fine structure constant is not a physical constant, but a mathematical one, like pi, but perhaps ... 14:13: And perhaps that number was 1/137, the fine  structure constant - whose value sets the rules of this particular space time. 06:37: So it’s starting to make sense why the fine structure constant appears in all of these formulas that depend on the electromagnetic force. 00:30: ... fine structure constant, designated as the greek letter alpha, just looks like one of the many constants of ... 05:55: And that’s exactly what the  fine structure constant is:   it’s the coupling strength of the electromagnetic force. 07:06: In fact the fine structure constant isn’t as constant as it sounds. 11:50: But without any units, it's not immediately clear what kind of relationship the Fine Structure Constant represents. 06:23: So the Fine Structure Constant sets the  "strength" of the electromagnetic force. 13:15: ... yet This is pretty speculative, but the specialness of  the fine structure constant warrants ... 09:08: But the fact that the fine structure constant  has such a convenient value isn’t the weirdest thing about it. 13:51: ... called the fine structure constant  “one of the greatest damn mysteries  of physics” and Poetically ... 03:54: ... this number only appeared in the formula  for the fine structure splitting of spectral lines it would be just a fun oddity, except this started to ... 08:22: ... been estimated that if the fine structure  constant were just a few percent different, carbon would never have ...
	2022-08-24: What Makes The Strong Force Strong? 13:56: ... are neutral, like black and white for example, you get this mathematical structure. ...
	2022-08-03: What Happens Inside a Proton? 05:14: ... 1/137 thing is the fine structure constant. It’s the coupling strength between the ... 06:02: ... strong coupling constant.   It is much higher than the fine structure constant, of order 1, though it depends on energy ... 12:15: ... isn’t really even a quantum problem any more.   The structure looks like a crystal - admittedly a 4-dimensional one, but a ... 05:14: ... and electromagnetic field. The smallness  of the fine structure constant means the   electromagnetic interaction is relatively  ... 06:02: ... strong coupling constant.   It is much higher than the fine structure constant, of order 1, though it depends on energy scale.   That’s what ...
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 02:19: ... Way’s mass.The entire galaxy is beautiful and intricately   structured. Weird to think that it built itself  into this through a life of ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 20:24: ... later development of large scale structure is defined by those density fluctuations, so in that sense cosmic ...
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 00:00: ... points   then there’ll be imperfections in the lattice  structure where the regions of spreading ice   meet - what we call ... 00:58: ... get ironed out, a little like how the complex   crystal structure of ice dissolves when it melts.  It seems pretty certain that in ...
	2022-02-10: The Nature of Space and Time AMA 00:03: ... that the speed of light has changed for example numbers like the fine structure constant are often considered more fundamental these are these ...
	2022-01-19: How To Build The Universe in a Computer 00:30: ... a series of whirling collisions, all spiral structure will be obliterated, gas will be compacted to produce waves of ... 05:36: ... if we keep enough precision to get the fine structure, it’s computationally impossible to also produce a large enough  ... 07:24: Adaptive particle meshes can be used to add higher resolution where needed - say, where the stars have higher density or structure. 10:02: ... to produce waves of star formation and supernovae, settling into spiral structures - just like we see in the real ...
	2021-12-29: How to Find ALIEN Dyson Spheres 10:56: ... and colour over time, as might be expected if a giant orbiting structure partially eclipses the star in an irregular ... 12:01: What we do know is that these structures are not very common through the Milky Way. 10:56: ... and colour over time, as might be expected if a giant orbiting structure partially eclipses the star in an irregular ... 12:01: What we do know is that these structures are not very common through the Milky Way.
	2021-11-17: Are Black Holes Actually Fuzzballs? 06:01: ... hole’s mass into a single point, it gets distributed around the ring structure of these ... 06:37: ... on the horizon- the number of possible configurations of stringy structures - the 1-D strings themselves and higher-dimensional structures called ... 08:06: ... you what these stringy black holes look like, or how they form, or how structure can actually be supported on the event ... 09:52: The ability for strings to maintain structure in this extreme gravity comes down to an effect specific to string theory called fractionation. 06:37: ... on the horizon- the number of possible configurations of stringy structures - the 1-D strings themselves and higher-dimensional structures called ...
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 10:44: Regular matter was kept from collapsing into  any structures by the pressure of the intense radiation of that era. 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. 10:44: Regular matter was kept from collapsing into  any structures by the pressure of the intense radiation of that era.
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 14:55: ... quantum spin leads to the universe as we know it - for example all the structure of solids, via the Pauli exclusion ...
	2021-09-21: How Electron Spin Makes Matter Possible 00:26: ... have this property is the entire reason that stuff in our universe has structure, and that matter doesn’t immediately collapse. It’s the source of the ... 14:26: ... there you have it - matter has structure and you don’t fall through your chair because electrons are ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 12:23: ... neutron star and even the protons and   neutrons start to lose structure and mush  together. This is all highly theoretical,   but ...
	2021-09-07: First Detection of Light from Behind a Black Hole 02:08: ... hole radiates and reflects - reverberates - its way through the complex structure of a ...
	2021-08-18: How Vacuum Decay Would Destroy The Universe 00:21: ... quantum fields were a bit different,   none of the familiar structures from atoms  to galaxies - would be possible. In fact,   ... 08:30: ... the properties of the elementary particles.   Life and structure could not exist as we know it, and may not exist at all. I should ... 00:21: ... quantum fields were a bit different,   none of the familiar structures from atoms  to galaxies - would be possible. In fact,   ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 00:23: ... mindlessly bumping and shoving each other, oblivious to the complex wave structure that they propagate. And that sound wave itself can be deconstructed ... 16:58: ... radiation. Galactic magnetic fields have very clear bubble-like structures that come from past ...
	2021-07-21: How Magnetism Shapes The Universe 00:56: And it governs the formation of every major structure in the universe, from the smallest moon to the largest cluster of galaxies. 01:51: That means magnetic fields can add up - and magnetism adds up to having enormous influence on the development of structure in our universe. 12:23: ... the radio light emitted by electrons that spiral slowly in these vast structures. ...
	2021-07-13: Where Are The Worlds In Many Worlds? 04:16: We never see the wavefunction - we only see measurements - we pluck our reality from this fantastically complex structure. 04:54: ... screen and then interferes with itself to produce a complex wavefunction structure. ...
	2021-07-07: Electrons DO NOT Spin 01:26: ... deeper property 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 ... 13:00: ... in their own energy levels and for matter   actually having structure. It’s the reason you don’t fall through the floor right now. But why ... 13:30: ... something far 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 ...
	2021-05-11: How To Know If It's Aliens 03:17: ... 1996, scientists discovered elongated mineral structures that looked for all the world like fossilized bacteria - but embedded ... 03:54: ... Over the past couple of decades, researchers have shown how these same structures - the “fossils” and the magnetite can be produced by the sort of ... 03:17: ... 1996, scientists discovered elongated mineral structures that looked for all the world like fossilized bacteria - but embedded ... 03:54: ... Over the past couple of decades, researchers have shown how these same structures - the “fossils” and the magnetite can be produced by the sort of ...
	2021-04-13: What If Dark Matter Is Just Black Holes? 10:11: ... of the structures of dwarf galaxies tells us that no more than 4% of the dark matter could ...
	2021-03-16: The NEW Crisis in Cosmology 08:03: ... moon,   Gaia scans the sky year after year, mapping the structure and motion of a good faction   of the Milky Way galaxy. Gaia ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... and provide a glimpse into the time before the big bang and reveal the structure of space time itself oh and we may have just detected it ligo itself may ...
	2021-01-26: Is Dark Matter Made of Particles? 05:06: In the early universe, that distance influenced the size of the seed structures which galaxies would later form from. 05:13: We’ve talked about that structure formation before. 05:16: Now, based on how that structure did end up forming, it seems likely that dark matter was moving pretty slowly. 05:13: We’ve talked about that structure formation before. 05:06: In the early universe, that distance influenced the size of the seed structures which galaxies would later form from.
	2020-12-22: Navigating with Quantum Entanglement 02:52: ... theories have suggested that birds have iron structures in their beaks which help them orient; others have proposed electrically ... 05:23: ... extremely weak field - far more than you could fit into the microscopic structures within a bird’s ... 02:52: ... theories have suggested that birds have iron structures in their beaks which help them orient; others have proposed electrically ... 05:23: ... extremely weak field - far more than you could fit into the microscopic structures within a bird’s ...
	2020-12-08: Why Do You Remember The Past But Not The Future? 02:40: ... built up into grains then tiny rocks then a ball of different mineral structures clumped ... 02:55: ... glassy grains, and those grains recall ancient heat in their crystal structures. ... 05:16: We’re totally ignoring quantum indeterminacy, or that any information might be lost from the internal structure of the proton. 06:34: ... just assembles from subatomic particles with all of its detailed structure mysteriously in place - cosmic ray tracks, embedded clumps, bumps and ... 08:06: ... no way you could predict that future cosmic ray strike with the internal structure of the asteroid ... 12:10: ... backwards to the big bang, wouldn’t entropy appear to increase as all structure disassembled and formed the homogeneous sea of hydrogen that preceded ... 06:34: ... just assembles from subatomic particles with all of its detailed structure mysteriously in place - cosmic ray tracks, embedded clumps, bumps and scratches, ... 02:40: ... built up into grains then tiny rocks then a ball of different mineral structures clumped ... 02:55: ... glassy grains, and those grains recall ancient heat in their crystal structures. ... 02:40: ... built up into grains then tiny rocks then a ball of different mineral structures clumped ...
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 08:49: ... future.   All of spacetime should be a smooth, if  curved structure - a manifold - cleanly   defined everywhere. Penrose showed ...
	2020-10-13: Do the Past and Future Exist? 03:01: But we can also imagine a perspective from outside both space AND time in which this entire structure just exists. 03:36: ... phenomena like the sequence of cause and effect, evolving patterns of structure and information, entropy, and even our conscious experience, which ... 04:50: There’s a name for this idea that all of time, future and past, sort of just exists as this atemporal structure.
	2020-09-28: Solving Quantum Cryptography 05:24: It turns out there’s a structure to factorization that can be exploited by quantum computers. 05:30: That structure is a period. 06:02: ... 18th century mathematician Leonhard Euler figured this structure extends to numbers that are the multiple of two prime numbers — just ...
	2020-09-21: Could Life Evolve Inside Stars? 00:39: Which is understandable - carbon-based chemistry enables the most complex structures that we know of in this universe. 01:03: ... cosmic strings beaded with magnetic monopoles - may evolve into complex structures, and even life, within ... 04:27: ... imagine a type of nuclear life, in which these chains form complex structures that can have a sort of chemistry - possibly even evolving into what we ... 06:36: In this way, it may be possible to develop complex string structures, analogous to chemistry. 00:39: Which is understandable - carbon-based chemistry enables the most complex structures that we know of in this universe. 01:03: ... cosmic strings beaded with magnetic monopoles - may evolve into complex structures, and even life, within ... 04:27: ... imagine a type of nuclear life, in which these chains form complex structures that can have a sort of chemistry - possibly even evolving into what we ... 06:36: In this way, it may be possible to develop complex string structures, analogous to chemistry.
	2020-08-24: Can Future Colliders Break the Standard Model? 11:26: It will smack electrons into protons and other nucleons to probe the details structure and interactions between quarks.
	2020-08-10: Theory of Everything Controversies: Livestream 00:00: ... still wondering at why the elementary particles and forces have the structure that they do the particular symmetries the particular arrangements of ...
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... gravity are in fact emergent properties of sort of the quantum qubit structure informational structure of spacetime right i mean even as an ...
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 08:16: ... the 2017 neutron star merger we learned a lot about the structure of these objects by the way they warped as they spiraled together, and ...
	2020-06-08: Can Viruses Travel Between Planets? 11:50: Would alien viruses have evolved to attack the same genetic structure?
	2020-05-27: Does Gravity Require Extra Dimensions? 15:33: ... black hole requires the assumption that the impossibly unstable inner structure of the Kerr spacetime doesn't collapse ...
	2020-05-18: Mapping the Multiverse 08:34: This time travel and naked singularity stuff is good reason to think this part of the mathematical structure of the Kerr black hole is NOT real. 12:42: ... this so-called mass inflation means the inner structure of the Kerr black hole is catastrophically unstable, and the whole thing ...
	2020-05-11: How Luminiferous Aether Led to Relativity 00:00: ... physicists know that one of those experiments would bring the entire structure crashing down paving the way for the physics revolutions of the 20th ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... next element and so patterns emerging and so all this amazing emergent structure appearing in the universe this notion is sometimes referred to as as ...
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 14:15: ... there. Okay so last week we talked about these bizarre giant, gamma ray structures, that seem to have erupted from near the Milky Way central black hole. ... 14:59: ... A lot of what you'll see is the galaxy NGC 3079, which has very similar structures to the Fermi bubbles, in this case observed with the Chandra x-ray ... 14:15: ... there. Okay so last week we talked about these bizarre giant, gamma ray structures, that seem to have erupted from near the Milky Way central black hole. ... 14:59: ... A lot of what you'll see is the galaxy NGC 3079, which has very similar structures to the Fermi bubbles, in this case observed with the Chandra x-ray ...
	2020-04-14: Was the Milky Way a Quasar? 03:06: Gamma rays produced by dark matter annihilations should have similar structure. 09:16: With jets alone, there’s no way to carve out structure quite like these bubbles from the interstellar medium. 09:23: AGN jets that get trapped within their galaxies tend to form more wedge-like shaped structures with internal structure - for example hotspots. 10:51: ... MeerKAT telescope array discovered a handful of never-before-seen radio structures throughout the Galaxy — including two bubble-shaped structures extending ... 11:25: ... biggest difference, however, is that these particular structures only extend 1400 light years above and below the plane of the Galaxy — ... 09:23: AGN jets that get trapped within their galaxies tend to form more wedge-like shaped structures with internal structure - for example hotspots. 10:51: ... MeerKAT telescope array discovered a handful of never-before-seen radio structures throughout the Galaxy — including two bubble-shaped structures extending ... 11:25: ... biggest difference, however, is that these particular structures only extend 1400 light years above and below the plane of the Galaxy — ... 10:51: ... radio structures throughout the Galaxy — including two bubble-shaped structures extending above and below the Galactic ...
	2020-04-07: How We Know The Earth Is Ancient 09:33: ... like zircon tend to incorporate uranium atoms into their crystal structure when forming, while at the same time repelling lead. So any lead you ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 12:33: ... network has this sort of collective consensus about those locations. The structure of macroscopic objects - including cats and dials - are strongly defined ...
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 15:46: You wouldn't get the same sort of energy structure by varying all of the other constants.
	2020-02-11: Are Axions Dark Matter? 03:59: ... one thing, the vacuum in QCD is full of weird structure. You might ask how can a vacuum, aka “nothing” have structure? Well, in ... 04:33: ... sort of simultaneously occupy all of those states at once. This bizarre structure for the vacuum alters the equations of motion that come from QCD, new ...
	2020-02-03: Are there Infinite Versions of You? 15:08: ... from the perspective of the virtual photon - what matters is the structure of the ...
	2020-01-27: Hacking the Nature of Reality 00:24: ... than trying to map the detailed inner workings of the invisible atomic structure - the traditional reductionist approach - he sought a model that ignored ... 03:24: Those nuclear particles were originally thought to be elementary - to have no internal structure, just like the electron. 03:40: ... experiments - particles were shot into atomic nuclei, and the internal structure was probed by the way those or other particles ... 05:26: Heisenberg sought a way to ignore that internal structure and, rather, treat the S-matrix itself as fundamental. 06:37: They attempted to build scattering matrices with no elementary particles at all, and with no details of nuclear structure. 07:36: ... large sets of Feynman diagram and helps us ignore the actual causal structure within the interaction ... 12:13: ... think that the largest structures in the universe today - galaxies and galaxy clusters - as collapsed from ... 00:24: ... than trying to map the detailed inner workings of the invisible atomic structure - the traditional reductionist approach - he sought a model that ignored ... 12:13: ... think that the largest structures in the universe today - galaxies and galaxy clusters - as collapsed from ...
	2019-11-18: Can You Observe a Typical Universe? 14:43: ... emerge in any universe, that universe must be capable of forming complex structures - whether or not it looks like life as we know ... 14:56: ... amount of time, have stable regions and energy sources for those structures to form, and have some building blocks - whether or not they look like ... 15:44: ... is somehow connected to the universe's later developing life and structure, why should it have landed on one of the rare combinations amenable to ... 14:43: ... emerge in any universe, that universe must be capable of forming complex structures - whether or not it looks like life as we know ... 14:56: ... amount of time, have stable regions and energy sources for those structures to form, and have some building blocks - whether or not they look like ... 14:43: ... emerge in any universe, that universe must be capable of forming complex structures - whether or not it looks like life as we know ...
	2019-11-11: Does Life Need a Multiverse to Exist? 04:10: ... which interact with each other according to their complex electron shell structures. ... 04:18: ... and a vast family of molecules, which in turn are capable of forming structures of incredible complexity - including ... 07:37: ... are set by the so-called coupling constants - for example, the fine structure constant for electromagnetism and the gravitational constant for ... 09:45: Such a universe would expand so quickly that no structure would ever form. 07:37: ... are set by the so-called coupling constants - for example, the fine structure constant for electromagnetism and the gravitational constant for ... 04:10: ... which interact with each other according to their complex electron shell structures. ... 04:18: ... and a vast family of molecules, which in turn are capable of forming structures of incredible complexity - including ...
	2019-10-15: Loop Quantum Gravity Explained 02:41: ... precisely, the metric - the object encapsulating the geometry and causal structure of spacetime - evolves in the equations of GR. So those equations need ...
	2019-10-07: Black Hole Harmonics 07:06: The rich structure of overtones in a musical instrument can tell you what instrument you’re listening to. 07:12: Similarly, the overtone structure of a black hole ringdown can identify the fundamental properties of that black hole – namely its mass and spin.
	2019-09-23: Is Pluto a Planet? 15:56: ... structures would be much, much smaller than a planet and so presumably easier to ...
	2019-08-19: What Happened Before the Big Bang? 07:53: But seeding all of the structure in our universe is probably the least impressive thing those quantum fluctuations did. 09:06: ... result is stunning; inflation never stops, but rather forms a fractal structure of infinitely expanding space in dispersed with bubble universes of all ...
	2019-08-12: Exploring Arecibo in VR 180 01:02: ... reflects light from every spot on the sky in a symmetric way the round structure the Gregorian dome contains two reflectors that correct the blurred ... 02:46: ... terrifying we're standing at the top of Arecibo Observatory on a 900 ton structure supported only by these cables suspended from giant concrete towers, but ...
	2019-08-06: What Caused the Big Bang? 10:59: ... ocean of matter and radiation that slowly cools and disperses and forms structure as the universe ...
	2019-07-25: Deciphering The Vast Scale of the Universe 07:51: Edwin Hubble never imagined such a structure.
	2019-07-01: Thorium and the Future of Nuclear Energy 02:49: ... in general is that they can be small because they don't need giant structures to handle the high pressure water in fact It was for use in submarines ...
	2019-06-20: The Quasar from The Beginning of Time 03:01: They keep the dome at the temperature of the upcoming night so that the giant structure doesn't warp and twist with the change in temperature.
	2019-06-06: The Alchemy of Neutron Star Collisions 02:47: ... do that it's pretty crazy and you can learn a lot about the large-scale structure of the universe by looking at these ...
	2019-04-10: The Holographic Universe Explained 05:43: We see scale invariance in fractal patterns, where the rules defining the structures repeat to infinitely large or small scales. 10:23: ... certain assumptions he found that the resulting braney structure looked just like a Minkowski spacetime of 3+1 dimensions on which their ... 11:46: ... coupled - then the corresponding higher-dimensional gravitational structures in the higher dimensional space would be weak and ... 10:23: ... certain assumptions he found that the resulting braney structure looked just like a Minkowski spacetime of 3+1 dimensions on which their lived a ... 05:43: We see scale invariance in fractal patterns, where the rules defining the structures repeat to infinitely large or small scales. 11:46: ... coupled - then the corresponding higher-dimensional gravitational structures in the higher dimensional space would be weak and ... 05:43: We see scale invariance in fractal patterns, where the rules defining the structures repeat to infinitely large or small scales.
	2019-04-03: The Edge of an Infinite Universe 13:53: Patterns on the surface define the structure of interior. 14:04: ... Minkowski space, that corresponded to an interesting mathematical structure in the enclosed 4+1-D AdS ... 14:20: That structure looked exactly like a string theory with gravity and everything.
	2019-03-28: Could the Universe End by Tearing Apart Every Atom? 08:10: That is the big room scenario, It happens when the cosmic event horizon is smaller than the smallest possible structure. 12:53: ... universe is ripped to shreds by the infinitely accelerating subatomic structure of ...
	2019-02-07: Sound Waves from the Beginning of Time 06:46: ... both dark matter and baryons flowed together and consolidated the new structure. Once more in the gravitational grip of dark matter, hydrogen and helium ...
	2019-01-30: Perpetual Motion From Negative Mass? 11:22: Either way, the structure of geodesics have inbuilt the assumption of the equivalence of gravitational and inertial mass.
	2018-11-07: Why String Theory is Right 11:00: They are quantizable in a way that other structures aren't. 13:10: But can such an elegant and rich mathematical structure really have nothing to do with reality? 11:00: They are quantizable in a way that other structures aren't.
	2018-10-25: Will We Ever Find Alien Life? 04:14: Thrillingly, one proposed explanation was an alien mega structure, perhaps a vast fleet of solar collectors built by the local inhabitants. 04:26: ... with dust, so likely natural space junk, not any type of artificial structure. ... 05:00: Let's call such a solar fleet a Dyson swarm after the Dyson sphere, which is the next level up, a structure that completely encases a star. 05:10: ... an unusual increase in infrared light due to waste heat shared by the structure. ...
	2018-10-18: What are the Strings in String Theory? 07:51: We have these Planck scale, one-dimensional structures that can be in loops or extended. 09:45: All this stuff sounds great, and by the way, doesn't work for any other geometrical structure other than a 1-D string. 07:51: We have these Planck scale, one-dimensional structures that can be in loops or extended.
	2018-10-10: Computing a Universe Simulation 01:04: ... atoms, and ultimately to all of the emergent laws of physics, physical structure, and ultimately the ...
	2018-10-03: How to Detect Extra Dimensions 06:07: ... can think of them as geometrical structures of potentially any number of dimensions on which the quantum field and ... 08:14: ... fact, the 3-brane itself, which defines the three-dimensional structure on which our observable universe exists, can actually expand into the ... 13:29: Something about its structure has to change on those scales. 06:07: ... can think of them as geometrical structures of potentially any number of dimensions on which the quantum field and ...
	2018-09-20: Quantum Gravity and the Hardest Problem in Physics 04:54: But even thinking about the structure of curved space on the smaller scales leads to craziness and catastrophic conflicts. 08:01: Given that sensible underlying structure, it's relatively routine to apply quantum principles, or quantize, most of the forces of nature.
	2018-08-30: Is There Life on Mars? 04:16: ... was mistranslated in English to "canals," implying artificially made structures. ... 07:42: That analysis revealed chain structures that look an awful lot like Earth's microfossils. 04:16: ... was mistranslated in English to "canals," implying artificially made structures. ... 07:42: That analysis revealed chain structures that look an awful lot like Earth's microfossils.
	2018-08-23: How Will the Universe End? 01:44: Life and structure can only exist as long as the universe is not in perfect equilibrium, what we call heat death. 09:29: In that case, there will be structure in the universe for a very, very long time.
	2018-08-15: Quantum Theory's Most Incredible Prediction 04:33: ... these electrons, changing their energy states, and resulting in the fine structure splitting of electron energy ... 04:42: The fine structure constant is named after this effect. 11:20: ... the QED calculations to a value for G, you also need to know the fine structure constant that I mentioned ... 11:41: So it's really the relationship between the electron magnetic moment and the fine structure constant that we're verifying. 04:42: The fine structure constant is named after this effect. 11:20: ... the QED calculations to a value for G, you also need to know the fine structure constant that I mentioned ... 11:41: So it's really the relationship between the electron magnetic moment and the fine structure constant that we're verifying. 04:33: ... these electrons, changing their energy states, and resulting in the fine structure splitting of electron energy ...
	2018-08-01: How Close To The Sun Can Humanity Get? 05:15: From that close up, it'll achieve unprecedented resolution of the solar wind, including shocks and other interesting structures.
	2018-07-25: Reversing Entropy with Maxwell's Demon 00:19: The second law of thermodynamics, the law that entropy must on average increase, has been interpreted as the inevitability of the decay of structure. 00:31: As we saw in our episode on the physics of life, structure can develop in one region even as the entropy of the universe rises. 04:39: So much for structure and organization always meaning low entropy, right? 09:12: You could turn information into work or into structure.
	2018-07-18: The Misunderstood Nature of Entropy 00:07: ... of the universe, and providing the driving force for the development of structure as well as decay and also excusing the messiness of your ...
	2018-06-20: The Black Hole Information Paradox 09:29: This led him to realize that the union of quantum mechanics and gravity may require that the entire 3D universe be a projection on a 2D structure.
	2018-05-09: How Gaia Changed Astronomy Forever 05:16: On the large scale, we see the distribution of stellar velocities through the spiral structure of our part of the Milky Way.
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 02:06: Life has a very low internal entropy because its structure is extremely specific and non-random. 09:28: While the global structure is disrupted, substructure develops. 09:32: Waves and vortices have their own complex and regular structures, but they ultimately serve to dissipate the flow.
	2018-03-28: The Andromeda-Milky Way Collision 00:38: ... has a beautiful spiral structure, spanning its gently rotating disk 220,000 light years in diameter, and a ... 05:35: The first impact in around four billion years completely disrupts the spiral structure of both galaxies, creating these amazing tidal tails. 08:37: ... whose visible stars revealed its great distance, and whose spiral structure helped us guess the shape of our own ... 09:49: ... be able to map the signal across the sky and so create images of the structures in which those first stars were forming, presumably some sort of ... 08:37: ... whose visible stars revealed its great distance, and whose spiral structure helped us guess the shape of our own ... 00:38: ... has a beautiful spiral structure, spanning its gently rotating disk 220,000 light years in diameter, and a central ... 09:49: ... be able to map the signal across the sky and so create images of the structures in which those first stars were forming, presumably some sort of ...
	2018-02-28: The Trebuchet Challenge 05:25: No energy is transferred to the structure of the trebuchet through friction or other motion.
	2018-01-17: Horizon Radiation 14:34: Complexity implies intricate structure, like a neural network. 14:40: Stellar interiors are more simple and chaotic than they are complex and structured.
	2018-01-10: What Do Stars Sound Like? 00:08: Twinkle, twinkle little star, how I wonder about your interior structure and dynamical properties. 01:23: You see, stars have a dynamical complexity far exceeding the simplest predictions of the equations describing stellar structure. 03:41: They start as traveling waves that can move throughout the stars in a structure. 04:15: Many modes vibrate at once, overlapping in a complex structure of resonance. 05:35: See, the nature of these modes depends on the internal structure, specifically on how the speed of sound changes throughout the star. 05:52: Helioseismology has allowed us to verify and improve the models of the sun's internal structure. 07:52: Most stellar seismology is focused on learning about the average global structure of stars.
	2017-10-25: The Missing Mass Mystery 01:59: Its gravity holds galaxies together and governed to the growth of large-scale structure in our universe throughout cosmic time. 03:55: It carries with it a map of the structure of the cosmos from those early times. 05:20: Supercomputer simulations reveal the shape of this large-scale structure that should result from this gravitational collapse. 05:43: Now surveys of galaxies confirm that this is what the large-scale structure of the universe looks like. 09:10: ... latest Planck satellite CMB map in the presumed locations of large-scale structure filaments, which they assumed was between pairs of nearby massive ...
	2017-09-28: Are the Fundamental Constants Changing? 03:33: Perhaps the most promising example is the fine structure constant. 03:50: We use the Greek letter Alpha to represent the fine structure constant. 04:18: ... of this fundamental parameter was through its effect on the fine grain structure of atomic energy levels, which is where the constant gets its ... 04:59: And if you look at their fine grained structure, you'll see that some lines are split in two, corresponding to very slightly different energies. 06:20: Well, the magnitude of this wavelength split depends very strongly on the fine structure constant. 07:05: Fine structure splitting in those absorption lines can then be used to track changes in Alpha through cosmic time. 08:43: And there are many other potential systematic errors the could masquerade as a change in the fine structure constant. 09:32: If the fine structure constant is changing, then it's not changing by very much. 13:25: And it may be possible to see structure on the surface of exoplanets. 13:55: I mean, crystal structures diffract x-rays. 14:02: To do something similar with visible light, you'd need a nanofabricated structure with actual concentric rings. 03:33: Perhaps the most promising example is the fine structure constant. 03:50: We use the Greek letter Alpha to represent the fine structure constant. 06:20: Well, the magnitude of this wavelength split depends very strongly on the fine structure constant. 08:43: And there are many other potential systematic errors the could masquerade as a change in the fine structure constant. 09:32: If the fine structure constant is changing, then it's not changing by very much. 07:05: Fine structure splitting in those absorption lines can then be used to track changes in Alpha through cosmic time. 04:59: And if you look at their fine grained structure, you'll see that some lines are split in two, corresponding to very slightly different energies. 13:55: I mean, crystal structures diffract x-rays.
	2017-09-20: The Future of Space Telescopes 07:41: ... planet at tens of light years distance and even map the cloud structure of a gas giant, especially if you add a starshade to the aragoscope-- ... 08:33: We've just seen ways to forego heavy glass mirrors and lenses, but what if we could ditch the giant disks and support structures too?
	2017-08-16: Extraterrestrial Superstorms 07:41: The answers to the storm's longevity and fate may be found in the details of its structure.
	2017-07-26: The Secrets of Feynman Diagrams 05:51: They sit on the shell structure you get when you plot Einstein's equation of energy, momentum, and mass.
	2017-07-19: The Real Star Wars 17:02: So the electric charge, which in turn depends on the fine structure constant. 17:07: In fact, the probability amplitude added at each vertex is proportional to the square root of the fine structure constant. 17:20: So that's the square root of 1/137 squared, which is just the fine structure constant, which is close to 1%. 17:40: Onlynamelefthere thinks our videos "are good and stuff, but will unsubscribe if we "set the fine structure constant to 1/100" once more. 17:53: You guys think you're so cool measuring the fine structure constant to better than 1 part in a billion. 17:02: So the electric charge, which in turn depends on the fine structure constant. 17:07: In fact, the probability amplitude added at each vertex is proportional to the square root of the fine structure constant. 17:20: So that's the square root of 1/137 squared, which is just the fine structure constant, which is close to 1%. 17:40: Onlynamelefthere thinks our videos "are good and stuff, but will unsubscribe if we "set the fine structure constant to 1/100" once more. 17:53: You guys think you're so cool measuring the fine structure constant to better than 1 part in a billion.
	2017-07-07: Feynman's Infinite Quantum Paths 03:01: That, in turn, has provided us with our clearest understanding of the fundamental structure of the subatomic world.
	2017-06-28: The First Quantum Field Theory 10:01: It predicts the relative value of the fine structure constant to a precision of one part in a billion. 14:02: ... just didn't work for electrons because it failed to predict the fine structure emission line energies in hydrogen due to not accounting for electron ... 10:01: It predicts the relative value of the fine structure constant to a precision of one part in a billion. 14:02: ... just didn't work for electrons because it failed to predict the fine structure emission line energies in hydrogen due to not accounting for electron ...
	2017-06-07: Supervoids vs Colliding Universes! 06:46: G23 has a similar void structure to the cold spot's line of sight plus a couple of overdensities.
	2017-05-17: Martian Evolution 01:27: Sets of genes defining skin pigmentation, height and build, immunities, even facial structure define the group.
	2017-04-26: Are You a Boltzmann Brain? 07:45: ... a universe where structure results from entropy fluctuations, the vast majority of conscious ...
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 01:14: And its purpose is to block the bright light of Fomalhaut so that its fate surrounding structures can be studied. 01:24: Sadly it's not a real part of the structure. 01:14: And its purpose is to block the bright light of Fomalhaut so that its fate surrounding structures can be studied.
	2017-02-15: Telescopes of Tomorrow 04:24: This fragile structure has the added benefit of blocking small space debris.
	2017-02-02: The Geometry of Causality 00:54: Today, we're going to look at the amazing geometric structure that time, or more accurately causality, imprints on the fabric of spacetime.
	2017-01-11: The EM Drive: Fact or Fantasy? 01:39: The structure of the EmDrive is a tapered copper cylinder with two flat ends. 10:39: ... an Earth-Mars interferometer could see that orange, well, crudely a structure 1,000 oranges across in the Alpha Cen ...
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 03:29: This has enabled EHT to map the strange magnetic field structures around the Sag A star black hole.
	2016-10-19: The First Humans on Mars 02:52: ... may be inflatable, modular structures, similar to those proposed by Mars One, or like the Bigelow Expandable ... 03:47: But with the advent of large-scale 3D printing, it's possible to build these structures on a planet's surface. 03:59: Some proposed harvesting the abundant iron and silica from the Martian soil to print a variety of structures. 02:52: ... may be inflatable, modular structures, similar to those proposed by Mars One, or like the Bigelow Expandable ... 03:47: But with the advent of large-scale 3D printing, it's possible to build these structures on a planet's surface. 03:59: Some proposed harvesting the abundant iron and silica from the Martian soil to print a variety of structures.
	2016-10-12: Black Holes from the Dawn of Time 05:44: As the heavier ones buzz around the galaxy, they should pull apart loosely bound binary systems and have an effect on the structure of star clusters.
	2016-10-05: Are We Alone? Galactic Civilization Challenge 05:22: Some people like to think this is evidence of some sort of alien mega structure eclipsing the star.
	2016-08-24: Should We Build a Dyson Sphere? 00:11: ... mega structures, capable of harvesting the power output of entire stars, the as yet ... 01:46: The incredible stresses on a solar structure that size are vastly greater than could be sustained by any known or yet imagined material. 06:47: Also, we need a mega structure to harvest it, with a raw material requirement close to that of all the terrestrial planets in the solar system. 00:11: ... mega structures, capable of harvesting the power output of entire stars, the as yet ...
	2016-06-15: The Strange Universe of Gravitational Lensing 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.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 04:51: So less vast alien mega structure slash planet destroyer and more Bond super-villain laser.
	2016-04-27: What Does Dark Energy Really Do? 12:24: Thanks to you for being honest about the strength of the evidence behind your belief structure.
	2016-03-23: How Cosmic Inflation Flattened the Universe 02:00: On a negative curvature hyperbolic plane-- a saddle-like structure-- they add up to less.
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 09:37: ... form the star in the center and the planets further out, but the disk structure remains long after all the gas is ...
	2016-01-13: When Time Breaks Down 07:38: But what is it about not traveling at the speed of light that allows matter to have structure and to change?
	2015-12-09: How to Build a Black Hole 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.
	2015-11-18: 5 Ways to Stop a Killer Asteroid 07:27: ... should break up a 500 meter asteroid nicely, although it depends on the structure of the ... 09:45: ... in this universe, the arrangement of atoms into molecules and molecular structures, via chemical bonds, seems to be the process most able to support extreme ...
	2015-11-05: Why Haven't We Found Alien Life? 08:34: ... those single cells to become complex enough to form large collaborative structures capable of collective reproduction, ...
	2015-10-28: Is The Alcubierre Warp Drive Possible? 09:14: Now, this is definitely not a clean geometric structure. 09:24: Although I imagine it could possibly be insanely vast ragtag colony of space structures surrounding a parent planet== except it's never aliens.
	2015-09-23: Does Dark Matter BREAK Physics? 05:59: ... to go from that highly smooth ocean of orange plasma to today's highly structured universe of clusters and galaxies, something had to act with enough ...
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 02:27: It turns out that there's a simple formula for how big the effective surface gravity produced by this rotating structure would be. 02:33: It's just the radius of the rotating structure multiplied by the square of its rotational speed in radians per second. 06:58: ... question, do any sci-fi franchises get all the physics right but with a structure that's compact enough that it's not entirely crazy to imagine humanity ... 02:33: It's just the radius of the rotating structure multiplied by the square of its rotational speed in radians per second.
	2015-04-15: Could NASA Start the Zombie Apocalypse? 02:11: Preliminary evidence suggests that the 3D structure of viral proteins, which dictates in part how viruses enter cells may be altered in micro gravity.

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