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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 05:29: ... between pressure, temperature and volume given by the Ideal Gas Law: ... 09:22: That means the supercritical equation of state is much more complex than the ideal gas law.
	2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table? 02:36: ... Segrè got hold of some Molybdenum foil that had been part of Ernest Lawrence’s newly invented cyclotron particle ...
	2022-10-19: The Equation That Explains (Nearly) Everything! 01:02: ... give rise to the fundamental forces. Gauge invariance says that the laws of physics should not care how certain properties of the world are ... 02:21: ... can be distorted in different ways that have no effect on the laws of nature. It’s just not as straightforward to say exactly what is being ... 01:02: ... give rise to the fundamental forces. Gauge invariance says that the laws of physics should not care how certain properties of the world are ... 02:21: ... can be distorted in different ways that have no effect on the laws of nature. It’s just not as straightforward to say exactly what is being ...
	2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics? 00:30: ... just looks like one of the many constants of nature  that power our laws of ... 03:16: We see combinations of these sorts of important  constants throughout the laws of physics. 04:34: And that’s just the tip of the iceberg for the appearances of the fine structure constant in the laws of physics. 00:30: ... just looks like one of the many constants of nature  that power our laws of ... 03:16: We see combinations of these sorts of important  constants throughout the laws of physics. 04:34: And that’s just the tip of the iceberg for the appearances of the fine structure constant in the laws of physics.
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 08:39: In this case, it’s by using a 350 year old law of physics known as conservation of momentum.
	2022-08-24: What Makes The Strong Force Strong? 14:14: ... symmetry is baked into the laws of physics and there it manifests as the Strong Force, but SU(3) is free ...
	2022-08-03: What Happens Inside a Proton? 00:22: ... of those rules seem to be mathematical.   By writing down the laws of physics as  equations, we can make predictions about   ... 12:15: ... We can now simulate how this lattice evolves over time using the laws of statistical ... 00:22: ... of those rules seem to be mathematical.   By writing down the laws of physics as  equations, we can make predictions about   ... 12:15: ... We can now simulate how this lattice evolves over time using the laws of statistical ...
	2022-07-20: What If We Live in a Superdeterministic Universe? 10:47: ... any system therein evolves in a way that’s uniquely predictable by the laws of physics and its initial ... 17:20: Dai Lixiuyuan and MrOvipare point out that we’d be able to tell what time "direction" the aliens use by their laws of thermodynamics. 17:34: The second law of thermodynamics says that entropy must increase in the forward time direction. 17:40: Their expression for the 2nd law should tell us what sign convention they use for time. 17:45: ... - any basic description of the universe they live in beyond the actual laws of physics would reveal ... 10:47: ... any system therein evolves in a way that’s uniquely predictable by the laws of physics and its initial ... 17:20: Dai Lixiuyuan and MrOvipare point out that we’d be able to tell what time "direction" the aliens use by their laws of thermodynamics. 17:45: ... - any basic description of the universe they live in beyond the actual laws of physics would reveal ...
	2022-06-30: Could We Decode Alien Physics? 00:00: ... known by the aliens - including the equations of   their laws of physics and a list of all elementary particles and their ... 01:25: ... but there’s no way to tell which was  chosen based on the laws of physics alone.  So we build the device with its  incorrect ... 02:20: Is there anything in the way the aliens wrote down their laws of physics that might reveal our error? 04:59: ... Franklin’s misguided choice doesn’t make any difference to the laws of   electromagnetism - the Maxwell’s equations. Those ... 05:20: ... we can’t rely on the equations describing   the laws of physics to determine the  alien sign convention for electric ... 05:33: ... And that fact   tells us that somewhere buried deep in the laws of physics is a subtle breaking of charge symmetry.  So in ... 06:55: ... not the only arbitrary choice we’ve  made in our development of the laws of physics.   What if alien physics made other ... 07:38: ... in convention does seem to change the actual equations of the laws of physics. To make   a LEFT-hand-rule work you need to either ... 10:41: ... mirror-reflected, antimatter universe has the   same laws of physics as ours. But actually,  such a universe works ... 11:52: ... the past as negative? Or do they do it the other way around? The laws of physics shouldn’t care   which you choose - so we say ... 14:09: ... systems. It contains our own confusingly   incomplete laws of physics. We actually ran out of space to include a lot of ... 00:00: ... known by the aliens - including the equations of   their laws of physics and a list of all elementary particles and their ... 01:25: ... but there’s no way to tell which was  chosen based on the laws of physics alone.  So we build the device with its  incorrect ... 02:20: Is there anything in the way the aliens wrote down their laws of physics that might reveal our error? 04:59: ... Franklin’s misguided choice doesn’t make any difference to the laws of   electromagnetism - the Maxwell’s equations. Those ... 05:20: ... we can’t rely on the equations describing   the laws of physics to determine the  alien sign convention for electric ... 05:33: ... And that fact   tells us that somewhere buried deep in the laws of physics is a subtle breaking of charge symmetry.  So in ... 06:55: ... not the only arbitrary choice we’ve  made in our development of the laws of physics.   What if alien physics made other ... 07:38: ... in convention does seem to change the actual equations of the laws of physics. To make   a LEFT-hand-rule work you need to either ... 10:41: ... mirror-reflected, antimatter universe has the   same laws of physics as ours. But actually,  such a universe works ... 11:52: ... the past as negative? Or do they do it the other way around? The laws of physics shouldn’t care   which you choose - so we say ... 14:09: ... systems. It contains our own confusingly   incomplete laws of physics. We actually ran out of space to include a lot of ... 04:59: ... Franklin’s misguided choice doesn’t make any difference to the laws of   electromagnetism - the Maxwell’s equations. Those equations tell us ... 05:33: ... And that fact   tells us that somewhere buried deep in the laws of physics is a subtle breaking of charge symmetry.  So in order to save the ...
	2022-06-15: Can Wormholes Solve The Black Hole Information Paradox? 01:40: ... is erased from the universe.  This conflicts with the law of   conservation of quantum information, which is ... 03:20: ... information seems like it should disappear, violating the law of conservation of quantum information and giving   all of its ... 07:24: ... And that includes paths that are impossible  according to the laws of physics. In a way,   the “classical” and sensible path that ... 01:40: ... is erased from the universe.  This conflicts with the law of   conservation of quantum information, which is a non-negotiable ... 07:24: ... And that includes paths that are impossible  according to the laws of physics. In a way,   the “classical” and sensible path that ...
	2022-06-01: What If Physics IS NOT Describing Reality? 00:25: ... is physics really trying to do? Is it to find  the mathematical laws that govern the universe?   Not quite - no one has to solve ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 02:04: ... often doesn’t  care what coordinate system you use.   The laws of physics are symmetric  under certain ... 02:26: We saw in our episode on Noether’s theorem that  these symmetries lead to conservation laws. 03:09: ... a symmetry of nature - in this case the fact   that the laws of physics are invariant  under changes in local phase. The ... 09:34: ... trick means requiring local   U(1) invariance. We need the laws of physics  to still make sense if there are rotations ... 02:04: ... often doesn’t  care what coordinate system you use.   The laws of physics are symmetric  under certain ... 02:26: We saw in our episode on Noether’s theorem that  these symmetries lead to conservation laws. 03:09: ... a symmetry of nature - in this case the fact   that the laws of physics are invariant  under changes in local phase. The ... 09:34: ... trick means requiring local   U(1) invariance. We need the laws of physics  to still make sense if there are rotations ...
	2022-03-23: Where Is The Center of The Universe? 01:06: ... the Copernican principle nor the Cosmological principle are actual laws of physics - they’re philosophical positions - guiding principles that ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 03:33: Proxima’s emissions lines seemed to shift back and forth from the wavelengths dictated by the laws of physics.
	2022-02-10: The Nature of Space and Time AMA 00:03: ... um uh theory in his physics project in which uh space and the laws of physics emerge from connections between points in a graph that have ...
	2022-01-19: How To Build The Universe in a Computer 02:23: He’d then adjust the velocities of all according to Newton’s laws. 03:53: In an N-Body simulation Newton’s laws of motion and gravity are applied over a series of time steps. 02:23: He’d then adjust the velocities of all according to Newton’s laws. 03:53: In an N-Body simulation Newton’s laws of motion and gravity are applied over a series of time steps.
	2022-01-12: How To Simulate The Universe With DFT 17:58: That might be the case, but it’s likely that the 2nd law of thermodynamics rules out perfect masking.
	2021-12-29: How to Find ALIEN Dyson Spheres 06:30: Stars are surprisingly simple beasts, for the most part ruled by laws of physics that we’ve understood for centuries.
	2021-11-17: Are Black Holes Actually Fuzzballs? 01:00: At the central singularity, the known laws of physics break down - general relativity comes into irreconcilable conflict with quantum mechanics. 03:34: And that violates a very deep and fundamental law - the law of conservation of quantum information. 01:00: At the central singularity, the known laws of physics break down - general relativity comes into irreconcilable conflict with quantum mechanics.
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass. 01:31: Or the laws of gravity could be wrong. 02:02: ... to Isaac Newton’s Law of Universal  Gravitation, the gravitational field drops off with ... 02:46: But what if gravity doesn’t obey Newton’s law of gravity? 03:53: ... can be done with a modification to either  Newton’s law of universal gravitation - in which case gravity has a minimum strength ... 04:50: Two: it needs to be consistent with   the other known laws and theories  of physics that are experimentally verified. 06:44: This is the Tully-Fisher Law. 06:57: Now those two are connected, but some believe  that their connection shouldn’t be so perfect to give the extremely tight Tully-Fisher law. 07:21: So, while the Tully-Fisher Law was already  known, we can sort of count it as a prediction of MOND. 08:15: ... be extracted in a way that automatically obeys all of our conservation laws. ... 08:50: ... gave the same results as MOND, except that  conservation laws were obeyed,   and because this was a relativistic theory it ... 13:10: ... naturally - like the flatness of rotation curves and the Tully-Fisher law. ... 16:23: It’s the symmetries of the Lagrangian via Noether’s theorem that yields our conservation laws and ultimately, well, all of physics. 06:47: ... a little surprising that the Tully-Fisher Law  is such a tight relationship because the rotation velocity depends on ... 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass. 01:31: Or the laws of gravity could be wrong. 04:50: Two: it needs to be consistent with   the other known laws and theories  of physics that are experimentally verified. 08:15: ... be extracted in a way that automatically obeys all of our conservation laws. ... 08:50: ... gave the same results as MOND, except that  conservation laws were obeyed,   and because this was a relativistic theory it ... 16:23: It’s the symmetries of the Lagrangian via Noether’s theorem that yields our conservation laws and ultimately, well, all of physics.
	2021-11-02: Is ACTION The Most Fundamental Property in Physics? 00:02: ... entropy and perhaps time itself. Ready? Action. In order to wrench the laws of physics from the reluctant clutches of nature, we need to watch for ... 01:22: ... energy - but to no avail. In the meantime Isaac Newton came up with his laws of motion which gave us the instant and miraculous power to explain the ... 05:52: ... to go that far. If the Principle of Least Action is really a fundamental law, then there should be a relativistic version of the Action that we can ... 17:24: ... down the space of all possible functions that might represent physical laws into the subset of functions that are consistent with the restrictions ... 00:02: ... entropy and perhaps time itself. Ready? Action. In order to wrench the laws of physics from the reluctant clutches of nature, we need to watch for ... 01:22: ... energy - but to no avail. In the meantime Isaac Newton came up with his laws of motion which gave us the instant and miraculous power to explain the ... 17:24: ... down the space of all possible functions that might represent physical laws into the subset of functions that are consistent with the restrictions ...
	2021-10-20: Will Constructor Theory REWRITE Physics? 00:46: the laws of thermodynamics or Newton’s laws of motion Step 3. 00:59: ... our entire modern world In short, physics works by applying dynamical laws to some input state in order to predict an output ... 01:11: We consider those laws to be “true” when these predictions match reality. 01:58: ... a century, our greatest minds have been trying to come up with dynamical laws that describe all of nature - a mechanistic theory of ... 02:40: ... and quantum mechanics, along with more fundamental conservation laws, or principles, to rule out impossible output states given an input state ... 04:36: But it also potentially allows us to understand aspects of nature where we don’t even know the dynamical laws. 05:11: We use that state as the input, apply the laws of gravity and motion - and we find the output state - that the apple fell to the ground. 05:31: ... laws of general relativity forbid this task: as a free-falling body the apple ... 05:44: Again, this task is impossible, since it’s ruled out by the laws of quantum mechanics and the principle of conservation of energy. 06:43: ... law of conservation of energy says that it’s impossible to create energy ... 07:15: There’s a whole family of rules and laws and theorems that say what can and can’t be. 07:21: ... together into chains of deductive reasoning to carve out our physical laws - they are the sculpture that’s left after we carve off all the “can’ts” ... 07:58: ... constructor theory can be applied even when we don’t know the dynamical laws of a system - when we don’t have a full mechanistic ... 09:55: It doesn't need the dynamical laws of such a theory, or even of quantum mechanics or general relativity as they currently stand. 10:51: ... energy levels - including  abandoning any pre-existing dynamical laws. ... 11:52: ... and isn’t possible in this universe,   you’ve decided that the laws of physics  should permit the existence of Space ... 00:46: the laws of thermodynamics or Newton’s laws of motion Step 3. 00:59: ... our entire modern world In short, physics works by applying dynamical laws to some input state in order to predict an output ... 01:11: We consider those laws to be “true” when these predictions match reality. 01:58: ... a century, our greatest minds have been trying to come up with dynamical laws that describe all of nature - a mechanistic theory of ... 02:40: ... and quantum mechanics, along with more fundamental conservation laws, or principles, to rule out impossible output states given an input state ... 04:36: But it also potentially allows us to understand aspects of nature where we don’t even know the dynamical laws. 05:11: We use that state as the input, apply the laws of gravity and motion - and we find the output state - that the apple fell to the ground. 05:31: ... laws of general relativity forbid this task: as a free-falling body the apple ... 05:44: Again, this task is impossible, since it’s ruled out by the laws of quantum mechanics and the principle of conservation of energy. 07:15: There’s a whole family of rules and laws and theorems that say what can and can’t be. 07:21: ... together into chains of deductive reasoning to carve out our physical laws - they are the sculpture that’s left after we carve off all the “can’ts” ... 07:58: ... constructor theory can be applied even when we don’t know the dynamical laws of a system - when we don’t have a full mechanistic ... 09:55: It doesn't need the dynamical laws of such a theory, or even of quantum mechanics or general relativity as they currently stand. 10:51: ... energy levels - including  abandoning any pre-existing dynamical laws. ... 11:52: ... and isn’t possible in this universe,   you’ve decided that the laws of physics  should permit the existence of Space ... 07:21: ... together into chains of deductive reasoning to carve out our physical laws - they are the sculpture that’s left after we carve off all the “can’ts” ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 01:43: There’s nothing in the laws of physics that could allow you to reach the other side of the hill. 01:48: Well, nothing in the laws of classical physics anyway. 01:43: There’s nothing in the laws of physics that could allow you to reach the other side of the hill. 01:48: Well, nothing in the laws of classical physics anyway.
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 02:27: In particular, Gauss’s law for magnetism, one of the four Maxwell’s equations. 02:57: According to this law there are no magnetic monopoles. 03:00: ... the other hand, Gauss’ law for electric fields tells us that the divergence of the electric field ... 10:13: ... the laws of physics shouldn’t care about the relative internal values of the ...
	2021-09-21: How Electron Spin Makes Matter Possible 14:58: ... That makes you some exotic form of matter, presumably unbound by the laws of known physics. So thank you for interacting with us lowly, fermionic ... 16:27: ... of enormous black holes was as awesome as all the others. Dave Lawrence rightly calls me out for saying that reverberation mapping can be done ... 14:58: ... That makes you some exotic form of matter, presumably unbound by the laws of known physics. So thank you for interacting with us lowly, fermionic ...
	2021-08-18: How Vacuum Decay Would Destroy The Universe 00:00: ... to be the most thorough - because  it could totally rewrite the laws of physics.   Today I hope to help you understand  ... 01:00: ... there’s   at least one mechanism that could rewrite  the laws of physics across the universe.   That mechanism is vacuum ... 08:30: ... vacuum states.   The decay of those could rewrite the  laws of physics in far more drastic ... 00:00: ... to be the most thorough - because  it could totally rewrite the laws of physics.   Today I hope to help you understand  ... 01:00: ... there’s   at least one mechanism that could rewrite  the laws of physics across the universe.   That mechanism is vacuum ... 08:30: ... vacuum states.   The decay of those could rewrite the  laws of physics in far more drastic ...
	2021-07-07: Electrons DO NOT Spin 10:33: ... Noter's theorem, the invariance  of the laws of motion to changes in coordinate location gives us the law of ...
	2021-06-23: How Quantum Entanglement Creates Entropy 00:00: ... physicists hold entropy to be behind  one of the most fundamental laws of ... 00:27: ... great astrophysicist Arthur Eddington  once said, “The law that entropy always   increases holds, I think, the ... 01:02: ... despite these clues to the importance of entropy and the 2nd law, it’s not obvious what   makes it so fundamental. A system’s ... 01:45: ... and laws as less fundamental than the properties and   laws governing individual particles. Entropy IS a thermodynamic ... 02:13: ... and understanding it may help us understand not just the 2nd law, but also the arrow of time   and how the large scale world ... 05:55: ... evolution of entanglement connections is  what drives the 2nd law of ... 10:15: ... forms of entropy,   and glimpse the real origin of the second law. ... 01:02: ... emergent property, and the   2nd law seems to be an emergent law. Emergent properties and laws arise from the statistical   behavior of large ... 00:27: ... as fundamental. As we’ve discussed in previous episodes, the 2nd law of   thermodynamics may be responsible for the arrow of time and is a ... 01:45: ... particles. Entropy IS a thermodynamic property, and the 2nd law   is the … well, second law of thermodynamics, so is also statistical ... 13:09: ... there you have it - the growth of  entanglement drives both the 2nd law   of thermodynamics AND the emergence of the classical world from the ... 00:00: ... physicists hold entropy to be behind  one of the most fundamental laws of ... 00:27: ... increases holds, I think, the supreme  position among the laws of Nature...   if your theory is found to be against the ... 01:02: ... 2nd law seems to be an emergent law. Emergent properties and laws arise from the statistical   behavior of large numbers of ... 01:45: ... and laws as less fundamental than the properties and   laws governing individual particles. Entropy IS a thermodynamic ...
	2021-05-19: Breaking The Heisenberg Uncertainty Principle 00:57: But neither engineers nor the physicists are content to let mere fundamental laws of nature stand in their way. 03:13: He thought the uncertainty principle was hinting at a far more fundamental law of the universe. 10:17: ... as long as we’re willing to bend a few fundamental laws - in this case, the Heisenberg uncertainty principle - we can push the ... 00:57: But neither engineers nor the physicists are content to let mere fundamental laws of nature stand in their way. 10:17: ... as long as we’re willing to bend a few fundamental laws - in this case, the Heisenberg uncertainty principle - we can push the ...
	2021-04-21: The NEW Warp Drive Possibilities 01:54: ... very rigorous, carefully calculated work of pure fiction - it broke the laws of physics in ways that I’ll come back ...
	2021-02-10: How Does Gravity Warp the Flow of Time? 01:00: ... at 1-g distant from any gravitational field - at least as far as the laws of physics are ...
	2021-01-26: Is Dark Matter Made of Particles? 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. 15:11: ... acceleration is fundamentally the same as gravitation as far as the laws of physics are ... 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. 15:11: ... acceleration is fundamentally the same as gravitation as far as the laws of physics are ...
	2020-12-22: Navigating with Quantum Entanglement 00:08: ... small groups of atoms, much too small to display exact statistical laws, do play a dominating role in the very orderly and lawful events within a ...
	2020-12-15: The Supernova At The End of Time 12:40: In other words, how does our psychological sense of the arrow of time arise when the laws of physics don't seem to care about the direction of time. 12:47: Ultimately it's connected to the second law of thermodynamics, which people keep commenting sounds like the sycamore of thermodynamics. 12:40: In other words, how does our psychological sense of the arrow of time arise when the laws of physics don't seem to care about the direction of time.
	2020-12-08: Why Do You Remember The Past But Not The Future? 00:00: The laws of physics don’t specify an arrow of time - they don’t distinguish the past from the future. 00:12: ... the brain is a thing and its ruled by the laws of physics - why does the brain and the conscious experience that ... 00:39: The 2nd law of thermodynamics dictates that entropy must rise over time. 04:11: ... but let’s look at this from the point of view of the timeless laws of physics and see if we can identify where the arrow of time enters the ... 05:38: If the laws of physics can exactly reconstruct the formation of the proton, those same laws can be used to project when the proton will decay. 09:14: ... one by one. This reversed time scenario doesn't actually break any laws of physics. It's just insanely unlikely. As unlikely as decreasing ... 11:52: ... our universe gains its directionality to time from entropy and the 2nd law of thermodynamics - or as Ryan Gallagher always hears it - the sycamore ... 00:00: The laws of physics don’t specify an arrow of time - they don’t distinguish the past from the future. 00:12: ... the brain is a thing and its ruled by the laws of physics - why does the brain and the conscious experience that ... 04:11: ... but let’s look at this from the point of view of the timeless laws of physics and see if we can identify where the arrow of time enters the ... 05:38: If the laws of physics can exactly reconstruct the formation of the proton, those same laws can be used to project when the proton will decay. 09:14: ... one by one. This reversed time scenario doesn't actually break any laws of physics. It's just insanely unlikely. As unlikely as decreasing ...
	2020-11-18: The Arrow of Time and How to Reverse It 00:00: ... could travel backwards in time and do things differently? Good news: the laws of physics seem to say traveling backwards in time is the same as ... 00:24: ... laws of physics describe how the universe at one instant evolves into the ... 01:38: ... what exactly do we mean when we say the laws of physics don’t care about the direction of time? Basically, if you ... 02:31: ... laws of motion combined with Coulomb’s law perfectly describe how the ... 02:53: ... the laws of physics don’t care about the direction of time. They just describe ... 03:12: ... is a powerful exception to this. The second law of thermodynamics states that this stuff called entropy must always ... 04:13: ... the energy in a system is. Higher entropy means more random. The second law of thermodynamics tells us that entropy must increase over time - which ... 04:50: ... this set the forward direction of time? Actually, it doesn’t. The 2nd law just tells us how a system is likely to change from a position of low ... 06:00: ... doesn’t care about the direction of time any more than the other laws of physics - it just wants to increase in adjacent time-steps, in either ... 06:19: ... particle interactions and you see perfect reversibility of the laws of physics, but zoom out and time’s arrow emerges. The presence of an ... 07:17: ... is the expansion of the universe, and it’s the manifestation of the 2nd law on the largest of scales. We know that entropy was lower in the past ... 08:11: ... a series of instances - slices of the block universe connected by the laws of physics, then we can break the symmetry in the direction of time if ... 02:31: ... laws of motion combined with Coulomb’s law perfectly describe how the electrons’ positions change over time. But if we flip ... 00:00: ... could travel backwards in time and do things differently? Good news: the laws of physics seem to say traveling backwards in time is the same as ... 00:24: ... laws of physics describe how the universe at one instant evolves into the ... 01:38: ... what exactly do we mean when we say the laws of physics don’t care about the direction of time? Basically, if you ... 02:31: ... laws of motion combined with Coulomb’s law perfectly describe how the ... 02:53: ... the laws of physics don’t care about the direction of time. They just describe ... 06:00: ... doesn’t care about the direction of time any more than the other laws of physics - it just wants to increase in adjacent time-steps, in either ... 06:19: ... particle interactions and you see perfect reversibility of the laws of physics, but zoom out and time’s arrow emerges. The presence of an ... 08:11: ... a series of instances - slices of the block universe connected by the laws of physics, then we can break the symmetry in the direction of time if ... 00:24: ... universe at one instant evolves into the universe at the next. But those laws don’t distinguish between the future and the past. Reverse the flow of time ... 02:53: ... past and future aren’t differentiated by the laws of physics. And those laws don’t even require time to “flow” - it’s just another dimension like ... 00:24: ... universe at one instant evolves into the universe at the next. But those laws don’t distinguish between the future and the past. Reverse the flow of time and their ...
	2020-11-11: Can Free Will be Saved in a Deterministic Universe? 00:57: ... positions and velocities of all particles, and perfect knowledge of the laws of nature could calculate perfectly all future states of the ... 01:14: ... and you've already accepted that matter follows the cold inviolable laws of nature, then your mind, every single thought, choice, decision, is ... 02:26: ... or the outcomes of quantum events are perfectly determined by quantum laws and the apparent randomness comes from our limited ... 02:55: We've talked about why this is such a fundamental law previously. 10:17: All possible futures exist and develop according to the laws of quantum mechanics. 00:57: ... positions and velocities of all particles, and perfect knowledge of the laws of nature could calculate perfectly all future states of the ... 01:14: ... and you've already accepted that matter follows the cold inviolable laws of nature, then your mind, every single thought, choice, decision, is ... 02:26: ... or the outcomes of quantum events are perfectly determined by quantum laws and the apparent randomness comes from our limited ... 10:17: All possible futures exist and develop according to the laws of quantum mechanics.
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 02:02: So an ingoing neutron is directly converted into the outgoing proton, electron and neutrino, with all the conservation laws satisfied.
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 00:34: ... When John Mitchell and Pierre-Simon Laplace explored Newton’s law of universal gravitation,   they realized the possibility of ...
	2020-10-20: Is The Future Predetermined By Quantum Mechanics? 01:44: They are connected by the unalterable laws of physics.
	2020-10-13: Do the Past and Future Exist? 01:21: Newton was the first to come up with a set of laws that allow us to predict the motion of all objects in the universe. 02:44: Every slice is the same universe at a particular instant, and it evolves from one slice to the next according to the laws of physics. 01:21: Newton was the first to come up with a set of laws that allow us to predict the motion of all objects in the universe. 02:44: Every slice is the same universe at a particular instant, and it evolves from one slice to the next according to the laws of physics.
	2020-10-05: Venus May Have Life! 15:02: I go for every second Moore’s law doubling, which leaves my machines basically paralyzed about half the time.
	2020-09-28: Solving Quantum Cryptography 13:58: ... key distribution proponents would rather put their faith in fundamental laws of physics - pretty darn secure if only we had a quantum ...
	2020-09-21: Could Life Evolve Inside Stars? 12:50: ... the simple intuitions of the likes of Einstein and Dirac that physical law should be mathematically ...
	2020-09-08: The Truth About Beauty in Physics 00:20: ... force towards truth - the more beautiful the equations of a proposed law of physics, the more likely it is to truly represent ... 02:04: Kepler’s three laws of planetary motion are arguably much less elegant than Copernicus’ simple model - a touch uglier. 02:19: There IS an extremely simple, elegant law underlying planetary motion - it's Newton’s Law of Universal Gravitation. 02:27: Not only can Kepler’s complicated laws be derived from Newton, but Newtonian gravity makes predictions far beyond the motion of the planets. 02:35: But even Newtonian gravity proved to be a special case of a much deeper law. 02:41: Einstein’s equations of general relativity give even better precision than Newton’s law - perhaps perfect precision - in their description of gravity. 03:48: ... orbits - and so surely nature must preferentially choose these for its laws. ... 04:17: ... in physics, when we talk about symmetry we mean that a physical law is unchanged by some transformation - whether shifts in time, space, ... 04:36: ... make powerful use of these symmetries to derive our laws of physics, and so perhaps it’s not surprising these equations possess ... 04:47: ... law of physics might also be considered beautiful if it reduces to a compact ... 04:58: If an ugly set of expressions reduces to one or few simple laws that explain a wide range of phenomena, that feels extremely compelling. 05:59: ... law of gravitation is a great example, and we can be sure that Newton ... 07:38: But if a physical law is mathematically ugly, then you can be sure it’s wrong, experiment or no. 08:20: Dirac knew he was on the right track based on an abstract sense that the underlying laws of the universe SHOULD be elegant. 09:09: The equations of physical law are beautiful if you get out more than you put in. 09:14: If it predicts or describes more aspects of the world than were used to derive the law in the first place. 02:41: Einstein’s equations of general relativity give even better precision than Newton’s law - perhaps perfect precision - in their description of gravity. 02:19: There IS an extremely simple, elegant law underlying planetary motion - it's Newton’s Law of Universal Gravitation. 02:04: Kepler’s three laws of planetary motion are arguably much less elegant than Copernicus’ simple model - a touch uglier. 02:27: Not only can Kepler’s complicated laws be derived from Newton, but Newtonian gravity makes predictions far beyond the motion of the planets. 03:48: ... orbits - and so surely nature must preferentially choose these for its laws. ... 04:36: ... make powerful use of these symmetries to derive our laws of physics, and so perhaps it’s not surprising these equations possess ... 04:58: If an ugly set of expressions reduces to one or few simple laws that explain a wide range of phenomena, that feels extremely compelling. 08:20: Dirac knew he was on the right track based on an abstract sense that the underlying laws of the universe SHOULD be elegant.
	2020-08-10: Theory of Everything Controversies: Livestream 00:00: ... joins us lee has been a central figure in our quest for the deepest laws of the universe for decades and has worked in many and perhaps all of ...
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... determined in part by how it functions at the micro level namely the laws of physics and so these uh these physicists who are so distinguished ...
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 02:12: ... be able to perform any of these transformations, or all of them, and the laws of physics should be unchanged. We have charge conjugation, where ...
	2020-06-30: Dissolving an Event Horizon 01:21: This would wreak havoc on our understanding of causality, and our precious laws of physics would become unhinged.
	2020-06-15: What Happens After the Universe Ends? 11:39: If entropy can only rise over time, per the second law of thermodynamics, how did it get so low at the start?
	2020-06-08: Can Viruses Travel Between Planets? 13:42: ... that the existence of hidden extra dimensions might change the law of gravity on the smallest scales, and we saw how the 120 year old ... 13:58: ... Sokic asks how we can know the inverse square law for gravity holds on the cosmic scales if we haven’t explained dark ... 14:11: In other words, maybe the inverse square law breaks down on large scales, producing the illusion of dark matter. 14:22: ... - in which gravity doesn’t drop off as quickly as the inverse square law when you get to very large ... 14:11: In other words, maybe the inverse square law breaks down on large scales, producing the illusion of dark matter.
	2020-05-27: Does Gravity Require Extra Dimensions? 00:33: ... first force to get a decent mathematical description with Isaac Newton’s Law of Universal Gravitation back in the 17th ... 01:49: The key is in understanding the inverse square law. 01:53: ... law of gravitation is an example of such a law - basically, the strength of ... 02:38: That’s where the r^2 comes from on the bottom of Newton’s law of gravitation. 03:09: ... - that surface would be 3-D, so gravity would follow an inverse cube law - that’s a faster drop ... 03:36: Newton’s inverse square law for gravity tells us there are 2+1 = 3 spatial dimensions. 05:03: In that case, gravity would only deviate from the inverse square law on the tiny scales of these compactified dimensions. 06:55: ... large scales, gravity would still follow the inverse square law, but would be diluted due to the hidden extra dimensions - and that could ... 07:36: It’s actually the OG - the experiment first used to measure the strength of the force of gravity - or the G in Newton’s law of gravitation. 10:53: ... expect a tiny and perhaps detectable deviation from the inverse square law several orders of magnitude larger than the size-scale of those ... 11:19: The inverse square law seems to hold down to the current limits of our measurements. 01:53: ... law of gravitation is an example of such a law - basically, the strength of the gravitational force drops off with the ... 03:09: ... - that surface would be 3-D, so gravity would follow an inverse cube law - that’s a faster drop ... 01:53: ... law of gravitation is an example of such a law - basically, the strength of the gravitational force drops off with the square of the ...
	2020-05-18: Mapping the Multiverse 10:37: ... not the bizarro negative time traveling universe either - here, the laws of physics are the same as where you started - at least as far as ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... and according to Stephen Wolfram you can basically recover the laws of physics and our universe from the this notion of a cellular ...
	2020-04-07: How We Know The Earth Is Ancient 04:32: ... - Earth is not in a privileged position in the universe, and so the laws of physics work the same everywhere. Hutton’s uniformitarianism is a ...
	2020-03-31: What’s On The Other Side Of A Black Hole? 14:15: ... entangled with their environment seems analogous to the second law of thermodynamics - aka that entropy must increase over ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 16:29: ... to new Big Bangs. Well, the key phrase here is "possible future". Do the laws of physics allow an entropy fluctuation large enough to produce a new ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 02:20: Over time the histories of a quantum system separate to represent every possible future the laws of physics allow.
	2020-02-11: Are Axions Dark Matter? 01:05: ... at one of the most powerful concepts in physics: symmetry. We expect the laws of physics to be symmetric with respect to certain properties of the ...
	2020-02-03: Are there Infinite Versions of You? 00:50: An infinite universe may literally contain every possible thing allowable by the laws of physics - each in infinite multitude. 04:36: ... COULD happen from the range of initial conditions developing under the laws of ... 07:12: I should also note that it’s not just the particles that define starting conditions, there’s also the laws of physics themselves. 07:24: ... universe - eventually leading to an exact-enough repetition of both the laws of physics AND the arrangement of ... 07:55: ... - and that tends to be prohibited by a combination of conservation laws and the formation of black ... 10:10: ... so unless there’s something weird hiding in the laws of physics that we don’t understand, an infinite universe probably does ... 00:50: An infinite universe may literally contain every possible thing allowable by the laws of physics - each in infinite multitude. 04:36: ... COULD happen from the range of initial conditions developing under the laws of ... 07:12: I should also note that it’s not just the particles that define starting conditions, there’s also the laws of physics themselves. 07:24: ... universe - eventually leading to an exact-enough repetition of both the laws of physics AND the arrangement of ... 07:55: ... - and that tends to be prohibited by a combination of conservation laws and the formation of black ... 10:10: ... so unless there’s something weird hiding in the laws of physics that we don’t understand, an infinite universe probably does ...
	2020-01-20: Solving the Three Body Problem 01:24: ... does it mean to find a solution to the three-body problem? Newton’s laws of motion and his law of universal gravitation give us a set of ... 02:06: ... the case of two gravitating bodies, the solutions to Newton’s laws are just the equations for the path traveled by the bodies - be it the ... 01:24: ... does it mean to find a solution to the three-body problem? Newton’s laws of motion and his law of universal gravitation give us a set of ... 02:06: ... the case of two gravitating bodies, the solutions to Newton’s laws are just the equations for the path traveled by the bodies - be it the ...
	2019-12-02: Is The Universe Finite? 12:30: ... of quantum mechanics and use them to construct equations of motion, laws of physics, and systems of measurement based on the algebra of quantum ...
	2019-11-18: Can You Observe a Typical Universe? 01:11: It’s extremely important - it allows us to study the distant universe confident that its laws of physics are the same as we experience on Earth. 06:16: ... second law of thermodynamics tells us that entropy can only increase, which means ... 01:11: It’s extremely important - it allows us to study the distant universe confident that its laws of physics are the same as we experience on Earth.
	2019-11-11: Does Life Need a Multiverse to Exist? 00:26: Our universe seems to operate according to a set of fundamental rules that we try to understand and model with the equations of our laws of physics.
	2019-10-21: Is Time Travel Impossible? 02:08: Of course we know that the laws of physics forbid faster than light travel. 09:25: But the weird thing is that we don’t know of one consistent, fundamental law in physics that prohibits true time travel. 10:04: It states that the laws of physics will always prevent time travel or allow it only when doesn’t cause paradoxes. 11:17: ... Thorn suggests there should probably be one fundamental law of physics that prohibits it - for example, the quantum vacuum may be ... 02:08: Of course we know that the laws of physics forbid faster than light travel. 10:04: It states that the laws of physics will always prevent time travel or allow it only when doesn’t cause paradoxes.
	2019-09-30: How Many Universes Are There? 05:33: Here’s another one: do all of these bubble universes the same laws of physics, or could they be wildly different from each other?
	2019-09-23: Is Pluto a Planet? 02:27: Newton’s Laws of Gravity led to consistent predictability of the motion of the heavenly spheres.
	2019-07-15: The Quantum Internet 04:18: ... is connected to the law of conservation of quantum information, which we’ve talked about before ...
	2019-05-16: The Cosmic Dark Ages 13:43: ... quantum states, in order to break quantum crypto you need to break the laws of physics - rather than just solve really hard math ...
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... proposed by Mordecai Milgram in the early 80s the idea is the Newton's law of universal gravitation might change between short distances like ...
	2019-04-03: The Edge of an Infinite Universe 16:25: ... sort of true - except that the law of conservation of energy has a very clear range of validity - it's ...
	2019-03-28: Could the Universe End by Tearing Apart Every Atom? 03:05: ... the second Friedman equation it's basically the equivalent of Newton's law of gravity for the whole universe describing the acceleration or ...
	2019-03-13: Will You Travel to Space? 15:29: Allen Ginsberg's interpretation of the three laws of thermodynamics. 15:34: It goes like this: Law 1: you can't win. 15:38: Law 2: you can't break even. 15:41: And Law 3: You can't stop playing. 15:34: It goes like this: Law 1: you can't win. 15:38: Law 2: you can't break even. 15:41: And Law 3: You can't stop playing. 15:29: Allen Ginsberg's interpretation of the three laws of thermodynamics.
	2019-03-06: The Impossibility of Perpetual Motion Machines 00:23: All break the laws of thermodynamics. 00:26: In fact, we classify them based on WHICH law of thermodynamics they break. 00:43: ... - they’re a bit more subtle in their wrongness because break the second law of thermodynamics - extracting energy by reversing ... 02:41: Now to be fair to the people working during the middle ages and Renaissance, the law of conservation of energy hadn’t been discovered yet. 03:02: Inventors just graduated to instead breaking the second law of thermodynamics. 03:07: ... review: the 2nd law states that entropy can never decrease over time – in other words, ... 03:37: Before we get to modern perpetual motion machines, let’s take a look at some actually interesting ideas that illustrate the limit of the second law. 05:56: But doesn’t break any laws of thermodynamics, so it’s not the first or second kind. 08:29: ... device to the second kind of perpetual motion: they violate the 2nd law of thermodynamics by extracting energy where there is no energy ... 12:11: “ da Vinci was ahead of his time in some ways – he knew perpetual motion was bunk even before the laws of thermodynamics came along. 03:07: ... review: the 2nd law states that entropy can never decrease over time – in other words, energy will ... 00:23: All break the laws of thermodynamics. 05:56: But doesn’t break any laws of thermodynamics, so it’s not the first or second kind. 12:11: “ da Vinci was ahead of his time in some ways – he knew perpetual motion was bunk even before the laws of thermodynamics came along.
	2019-01-30: Perpetual Motion From Negative Mass? 01:34: This is encapsulated in Newton’s second law, which defines the connection between the amount of force applied and the acceleration that results. 01:52: It appears in Newton’s Law of Universal Gravitation. 02:35: ... Newton’s second law with the law of gravitation and you see that although massive objects ... 04:37: Newton’s second law seems to say that negative inertial masses respond oppositely to the applied force. 05:47: ... fact Newton’s law of gravitation is really only approximation of a much more complete ... 10:39: We then happily plugged our negative inertial mass into Newton’s 2nd law to get acceleration. 10:58: ... geometry of Einstein’s spacetime – are the GR analogs of Newton’s second law and give the equations of motion of ... 11:10: ... or from Lagrangian mechanics – a more modern version of Newton’s laws of ...
	2019-01-24: The Crisis in Cosmology 16:03: ...but the laws of Physics are the same.
	2019-01-16: Our Antimatter, Mirrored, Time-Reversed Universe 00:42: ... the same way except counterclockwise - our intuition would be wrong. The laws of physics and so the laws of clocks are not symmetric to this sort of ... 03:02: ... time reversed version of our universe should have exactly the same laws of physics this is the CPT theorem. Quantum field theory should be ... 00:42: ... the same way except counterclockwise - our intuition would be wrong. The laws of physics and so the laws of clocks are not symmetric to this sort of ... 03:02: ... time reversed version of our universe should have exactly the same laws of physics this is the CPT theorem. Quantum field theory should be ...
	2019-01-09: Are Dark Matter And Dark Energy The Same? 04:18: The answer is complicated - it’s not always obvious how weird stuff like negative masses translates from general relativity to Newton’s laws. 05:09: It also determines the way objects respond to forces via Newton’s 2nd Law. 06:22: ... and negative mass particles, along with his interpretations of Newton’s laws. ... 08:18: ... at the second Friedmann equation, which is really the analog of Newton’s law of gravity for the whole cosmos, this negative mass fluid – as a ... 04:18: The answer is complicated - it’s not always obvious how weird stuff like negative masses translates from general relativity to Newton’s laws. 06:22: ... and negative mass particles, along with his interpretations of Newton’s laws. ...
	2018-12-20: Why String Theory is Wrong 13:08: ... vibrating strings, and so a different family of particles and different laws of physics to go with ... 15:37: ... that's spatially reflected in a mirror has fundamentally different laws of physics to our own you had your own Reflections on the subject. socks ... 13:08: ... vibrating strings, and so a different family of particles and different laws of physics to go with ... 15:37: ... that's spatially reflected in a mirror has fundamentally different laws of physics to our own you had your own Reflections on the subject. socks ...
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... see a perfect reflection but you're actually looking at a universe whose laws are fundamentally different when we think about symmetry the first thing ...
	2018-11-21: 'Oumuamua Is Not Aliens 04:36: In fact, the observed acceleration seems to be following an inverse square law.
	2018-11-07: Why String Theory is Right 08:32: It breaks various laws of physics.
	2018-10-31: Are Virtual Particles A New Layer of Reality? 12:31: ... he was onto something because there was no way to express his Planck law without an artifact of that quantum nature-- namely, the Planck ...
	2018-10-25: Will We Ever Find Alien Life? 15:41: ... science speak, a scientific theory is a well-developed suite of ideas, laws, models, and predictive tools that attempts to explain an aspect of the ...
	2018-10-10: Computing a Universe Simulation 01:04: ... elementary particles, atoms, and ultimately to all of the emergent laws of physics, physical structure, and ultimately the ... 02:50: The laws of physics prescribe fundamental limits on both. 01:04: ... elementary particles, atoms, and ultimately to all of the emergent laws of physics, physical structure, and ultimately the ... 02:50: The laws of physics prescribe fundamental limits on both.
	2018-10-03: How to Detect Extra Dimensions 03:22: This is the famous inverse square law. 04:07: In our universe, gravity appears to diminish according to the inverse square law, as reflected in Newton's law of universal gravitation. 06:55: ... in three spatial dimensions-- for example, the usual inverse square law for ... 07:05: On some spatial scales, you even get the inverse square law for gravity. 07:59: ... on how you tweak the theory, gravity can obey an inverse square law on galactic scales, where it's sort of coupled to the three spatial ... 08:10: But it starts to obey the inverse cubed law on much larger scales. 08:58: Wild light and the force of gravity appear to obey the inverse square law.
	2018-09-05: The Black Hole Entropy Enigma 01:15: But they also present an apparent conflict with the notion of entropy and the second law of thermodynamics. 04:12: ... so the second law of thermodynamics states that entropy of an isolated system must always ... 05:07: ... from high entropy to zero entropy in an instant, shattering the second law in the process, which, to put it mildly, is a ... 05:35: Actually, yeah, the resolution to the information paradox also saves the second law of thermodynamics. 05:49: ... was this seeming violation of the second law that got Jacob Bekenstein thinking about the connection between black ... 10:01: The second law of thermodynamics is saved because black holes do have entropy.
	2018-08-23: How Will the Universe End? 12:23: Vacuum decay may drop the universe to an even lower energy state, wiping out the laws of physics as we know them.
	2018-08-01: How Close To The Sun Can Humanity Get? 10:04: Thereby, decreasing entropy against the second law of thermodynamics.
	2018-07-25: Reversing Entropy with Maxwell's Demon 00:03: MATT O'DOWD: Can a demon defeat the second law of thermodynamics? 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. 05:06: ... up with a thought experiment to explore just how fundamental the second law of thermodynamics really ... 06:26: ... seems to violate the second law of thermodynamics, which demands entropy remain constant or increase, ... 06:35: Believe it or not, Maxwell's demon was seen as a serious problem for the second law for many years. 08:13: Either way the second law is preserved. 11:17: ... quantum entanglement may be the ultimate source of entropy, the second law, the limits of information processing, and even the arrow of ... 11:30: ... we delved into the true nature of entropy and the cause of the second law of ...
	2018-07-18: The Misunderstood Nature of Entropy 00:07: ... and the second law of thermodynamics have been credited with defying the arrow of time, ... 00:38: The entropy of the universe must always increase, so says the second law of thermodynamics. 00:44: It's a law that seems emergent from deeper laws. 00:47: It's statistical in nature, and yet, may ultimately be more fundamental and unavoidable than any other law in physics. 00:54: ... said that "the thermodynamics that encapsulates the second law is the only physical theory of universal content which I am convinced ... 01:34: But today, we'll see what entropy really is and why the second law of thermodynamics is considered to be so fundamental and so unavoidable. 03:57: This theory explained thermodynamic behavior as the summed result of the individual motion of tiny particles under Newton's laws of motion. 05:06: ... eventually try out all possible microstates that are possible given the laws of ... 08:21: Order is not the same thing as low entropy, and the second law isn't always the tendency towards disorder. 09:41: ... mechanics inevitably leads to entropy and the second law, and it does so by something so fundamental and basic that it's ... 10:04: But entropy is also statistical and emerges from behavior of particles under the laws of motion. 10:11: This is where the second law appears to add something new to the universe not seen in the more fundamental laws. 10:22: ... the laws of motion, whether Newtonian or quantum mechanical, don't care about the ... 10:11: This is where the second law appears to add something new to the universe not seen in the more fundamental laws. 08:21: Order is not the same thing as low entropy, and the second law isn't always the tendency towards disorder. 00:44: It's a law that seems emergent from deeper laws. 03:57: This theory explained thermodynamic behavior as the summed result of the individual motion of tiny particles under Newton's laws of motion. 05:06: ... eventually try out all possible microstates that are possible given the laws of ... 10:04: But entropy is also statistical and emerges from behavior of particles under the laws of motion. 10:11: This is where the second law appears to add something new to the universe not seen in the more fundamental laws. 10:22: ... the laws of motion, whether Newtonian or quantum mechanical, don't care about the ...
	2018-07-11: Quantum Invariance & The Origin of The Standard Model 00:33: Our laws of physics are equations of motion tuned by the fundamental constants. 02:03: Newton's laws of motion and gravity, Maxwell's equations for electromagnetism, Einstein's general relativity, and of course, the standard model. 00:33: Our laws of physics are equations of motion tuned by the fundamental constants. 02:03: Newton's laws of motion and gravity, Maxwell's equations for electromagnetism, Einstein's general relativity, and of course, the standard model.
	2018-06-20: The Black Hole Information Paradox 01:33: First, we looked at the law of conservation of quantum information. 02:27: ... there's nothing about the law of conservation of information that requires information to remain ... 07:16: ... quantum information to Hawking radiation, you may still violate the law of conservation of information just as much as you would by deleting ... 11:54: They were glimpsed as dark stars in the mathematics of Isaac Newton's law of universal gravitation. 12:07: ... series on gravitational physics that will take you from Newton's law all the way through gravitational field and celestial ...
	2018-06-13: What Survives Inside A Black Hole? 04:46: There's an extremely important law in physics that describes how the universe remembers the contents of a region of space. 04:53: It's Gauss's law, which applies to both gravitational and electric fields. 04:58: ... law of gravity states that the total gravitational field added up over an ... 05:36: Now, the original Gauss's law actually applies to the electric field. 05:47: ... law for the electric field says that the total electric flux passing through ... 06:23: Both obey an inverse-square law. 06:26: ... law of universal gravitation and Coulomb's law for electrostatics say that ... 07:00: In fact, Gauss's law is a more general form of these inverse-square laws. 07:08: But both Gauss's law and the inverse-square law work because of a key similarity between gravity and the electric field. 07:34: ... and electromagnetic forces have infinite range, and so Gauss's law demands that the mass and charge content of any region of space are ... 07:08: But both Gauss's law and the inverse-square law work because of a key similarity between gravity and the electric field. 07:00: In fact, Gauss's law is a more general form of these inverse-square laws.
	2018-05-23: Why Quantum Information is Never Destroyed 00:07: If you have perfect knowledge of every single particle in the universe, can you use the laws of physics to rewind all the way back to the Big Bang? 00:23: [MUSIC PLAYING] The laws of physics are equations of motion. 00:44: These laws can be used to predict how the universe will evolve into the future. 00:59: But determinism in the forward time direction does not guarantee that the same laws can perfectly predict the past. 01:23: In a future episode, we'll see how this law might be broken by black holes. 01:28: An important tool for making predictions with the laws of physics are the conservation laws that we derive from them. 02:14: Time-reversal symmetry isn't covered by Noether's theorem, but it's still tied to a conservation law. 03:25: It's possible for the future to be perfectly predictable by the laws of physics while the past is not. 03:50: And the laws of motion say that A becomes C and B becomes D. If we look at the later state and see state C, we know A came first. 04:21: We just set things up so our laws of motion force two possible initial states into the same exact final state. 11:03: Noether's theorem predicts the conservation laws of physics from the symmetries of nature. 00:07: If you have perfect knowledge of every single particle in the universe, can you use the laws of physics to rewind all the way back to the Big Bang? 00:23: [MUSIC PLAYING] The laws of physics are equations of motion. 00:44: These laws can be used to predict how the universe will evolve into the future. 00:59: But determinism in the forward time direction does not guarantee that the same laws can perfectly predict the past. 01:28: An important tool for making predictions with the laws of physics are the conservation laws that we derive from them. 03:25: It's possible for the future to be perfectly predictable by the laws of physics while the past is not. 03:50: And the laws of motion say that A becomes C and B becomes D. If we look at the later state and see state C, we know A came first. 04:21: We just set things up so our laws of motion force two possible initial states into the same exact final state. 11:03: Noether's theorem predicts the conservation laws of physics from the symmetries of nature.
	2018-05-16: Noether's Theorem and The Symmetries of Reality 00:07: Conservation laws are among the most important tools in physics. 00:17: These laws are consequences of a much deeper, more fundamental principle. 00:23: [MUSIC PLAYING] Conservation laws are the cheat codes of physics. 00:37: More than cheat codes, conservation laws are clues to the source code. 00:49: The connection between conservation laws and symmetry is encapsulated in Noether's theorem. 01:49: She discovered why the law of conservation of energy broke down in general relativity. 01:54: The law was not fundamental after all. 01:57: She realized that all conservation laws arise from a more fundamental relationship, which we call Noether's theorem. 03:03: In the case of Noether's theorem, when we say the environment stays the same, we mean the equations that give the laws of motion for the system. 04:07: ... the last classic example, if the factors driving the laws of motion are symmetric under rotation-- for example, the ... 04:23: By revealing the underlying source of conservation laws, Noether's theorem handily explains when and why they are broken. 05:00: The law of conservation of energy is fundamental in Newtonian mechanics, in which space and time are unvarying and eternal. 06:43: ... principle of least action can be used to derive the laws of motion from the equations of classical mechanics to Feynman's path ... 12:10: ... fitting laws of motion to the stars' five-year trajectory, there's only a very narrow ... 00:07: Conservation laws are among the most important tools in physics. 00:17: These laws are consequences of a much deeper, more fundamental principle. 00:23: [MUSIC PLAYING] Conservation laws are the cheat codes of physics. 00:37: More than cheat codes, conservation laws are clues to the source code. 00:49: The connection between conservation laws and symmetry is encapsulated in Noether's theorem. 01:57: She realized that all conservation laws arise from a more fundamental relationship, which we call Noether's theorem. 03:03: In the case of Noether's theorem, when we say the environment stays the same, we mean the equations that give the laws of motion for the system. 04:07: ... the last classic example, if the factors driving the laws of motion are symmetric under rotation-- for example, the ... 04:23: By revealing the underlying source of conservation laws, Noether's theorem handily explains when and why they are broken. 06:43: ... principle of least action can be used to derive the laws of motion from the equations of classical mechanics to Feynman's path ... 12:10: ... fitting laws of motion to the stars' five-year trajectory, there's only a very narrow ... 04:23: By revealing the underlying source of conservation laws, Noether's theorem handily explains when and why they are broken.
	2018-05-02: The Star at the End of Time 04:58: This is thermal or black-body radiation, and it obeys a couple of very strict laws.
	2018-04-25: Black Hole Swarms 10:13: That is, the laws of physics allow it, the laws of engineering may beg to differ.
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 00:11: Actually, the laws of physics themselves may demand it. 01:48: The second law of thermodynamics tells us that a closed system will only increase in entropy. 01:57: But there's one type of system that seems to resist the second law of thermodynamics and maintain low entropy. 03:20: ... this presentation and increase in order appears to contradict the second law of thermodynamics-- entropy appears to either stay constant or ... 03:34: But let me be clear, there is no violation of the second law. 03:39: The second law tells us that closed systems must increase in entropy. 06:20: These systems are doing their best to obey the second law of thermodynamics by redistributing their energy as evenly and randomly as they can. 06:29: ... energy is also dispersed into every form it can take consistent with the laws of ... 10:20: These blips in order are actually serving the second law helping the universe disperse its early extreme low entropy state. 03:39: The second law tells us that closed systems must increase in entropy. 00:11: Actually, the laws of physics themselves may demand it. 06:29: ... energy is also dispersed into every form it can take consistent with the laws of ...
	2018-03-28: The Andromeda-Milky Way Collision 10:06: ... the visible matter given our understanding of that matter and/or the laws of ...
	2018-02-28: The Trebuchet Challenge 01:43: ... Newton's laws tell us that when two objects with different masses are accelerated by ... 04:46: ... figure out the equations of motion of a trebuchet in terms of Newton's laws, with a complicated series of force vectors, some gnarly geometry, and of ... 05:04: The law of conservation of energy tells us that the sum of kinetic and potential energies of the projectile and the counterweight are conserved. 01:43: ... Newton's laws tell us that when two objects with different masses are accelerated by ... 04:46: ... figure out the equations of motion of a trebuchet in terms of Newton's laws, with a complicated series of force vectors, some gnarly geometry, and of ...
	2018-02-14: What is Energy? 02:20: When she introduced the idea of gravitational potential energy, she put the laws of conservation of energy and momentum on equal footing. 02:40: The law of conservation of energy is an incredibly powerful tool. 09:45: See, the law of conservation of energy arises because of symmetry, in particular time translational symmetry. 10:06: For example, the law of conservation of momentum is due to spatial translation symmetry. 10:16: ... relationship between conservation laws and symmetries was discovered by mathematician Emmy Noether and ... 00:31: You can lose it by mowing the lawn. 02:20: When she introduced the idea of gravitational potential energy, she put the laws of conservation of energy and momentum on equal footing. 10:16: ... relationship between conservation laws and symmetries was discovered by mathematician Emmy Noether and ...
	2018-01-17: Horizon Radiation 00:37: Different observers might disagree about speeds, lengths, or times, but the laws of physics should be the same for everyone. 01:34: ... fundamental laws of physics shouldn't change if we go near a black hole or if we start ... 02:56: The laws of physics, as we know them, are the rules defining how particles interact. 03:00: For the laws of physics to be consistent, the fundamental properties of these fields must be the same for all observers. 03:44: ... cleanly between inertial reference frames in a way that leaves the laws of physics and the nature of the vacuum ... 03:55: ... a horizon tries to write down these equations, in order to preserve the laws of physics, they find they have to redefine the nature of the vacuum, ... 09:04: Here, the field operator represents the field properties or the laws of physics. 10:38: We need to rejig the field operator for the laws of physics to be consistent. 00:37: Different observers might disagree about speeds, lengths, or times, but the laws of physics should be the same for everyone. 01:34: ... fundamental laws of physics shouldn't change if we go near a black hole or if we start ... 02:56: The laws of physics, as we know them, are the rules defining how particles interact. 03:00: For the laws of physics to be consistent, the fundamental properties of these fields must be the same for all observers. 03:44: ... cleanly between inertial reference frames in a way that leaves the laws of physics and the nature of the vacuum ... 03:55: ... a horizon tries to write down these equations, in order to preserve the laws of physics, they find they have to redefine the nature of the vacuum, ... 09:04: Here, the field operator represents the field properties or the laws of physics. 10:38: We need to rejig the field operator for the laws of physics to be consistent.
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 03:00: ... in our solar system-- moves in elliptical orbits as governed by Kepler's laws. ...
	2017-11-22: Suicide Space Robots 13:33: But given the fact that the EmDrive defies the laws of physics, the true source of the thrust almost certainly lies within these systematics.
	2017-11-08: Zero-Point Energy Demystified 02:13: Well, the answer lies in entropy and the second law of thermodynamics. 02:37: And that's the second law of thermodynamics right there.
	2017-10-25: The Missing Mass Mystery 11:59: ... would introduce energy into the universe and therefore violate the law of conservation of ...
	2017-10-19: The Nature of Nothing 05:24: For example, quantum conservation laws must be obeyed, so most virtual particles are created in particle-antiparticle pairs. 14:26: ... large range, but always have a distribution characterized by the Planck law, basically a lopsided bell ... 05:24: For example, quantum conservation laws must be obeyed, so most virtual particles are created in particle-antiparticle pairs.
	2017-10-11: Absolute Cold 02:23: This is the black-body radiation described by Planck's Law. 04:59: However, the most fundamental law of quantum mechanics forbids this.
	2017-10-04: When Quasars Collide STJC 11:50: ... the entirety of our universe-- or even the multiverse-- has the same laws of physics, including the same fundamental ...
	2017-09-28: Are the Fundamental Constants Changing? 00:06: The laws of physics are the same everywhere in the universe-- at least, we astrophysicists hope so. 00:30: [MUSIC PLAYING] The laws of physics are the relationships we observe between space and time, and the fields and particles that occupy it. 06:16: OK, but what's all this got to do with the laws of physics changing? 11:04: We may one day find that our sacred laws of physics and their underlying constants aren't so constant after all beyond our little patch of space time. 00:06: The laws of physics are the same everywhere in the universe-- at least, we astrophysicists hope so. 00:30: [MUSIC PLAYING] The laws of physics are the relationships we observe between space and time, and the fields and particles that occupy it. 06:16: OK, but what's all this got to do with the laws of physics changing? 11:04: We may one day find that our sacred laws of physics and their underlying constants aren't so constant after all beyond our little patch of space time.
	2017-08-30: White Holes 09:12: ... possible to build a white hole in general relativity, there are other laws of physics that the universe needs to obey-- for example, the second law ... 09:29: This law defines the direction of the flow of time. 09:32: To reverse time, you need to break the law. 09:29: This law defines the direction of the flow of time. 09:12: ... possible to build a white hole in general relativity, there are other laws of physics that the universe needs to obey-- for example, the second law ...
	2017-08-02: Dark Flow 01:27: The laws of physics work the same no matter your speed.
	2017-07-26: The Secrets of Feynman Diagrams 04:35: ... because of conservation laws-- energy and momentum conservation requires that particles not just vanish ...
	2017-07-12: Solving the Impossible in Quantum Field Theory 12:33: This week, we'd like to give an extra big thanks to Eugene Lawson, who's contributing at the Big Bang level.
	2017-06-21: Anti-Matter and Quantum Relativity 15:28: ... Richard Feynman's "The Character of Physical Law." And one of Feynman's greatest talents was his uncanny ability to see the ...
	2017-05-31: The Fate of the First Stars 04:30: And by the ideal gas law, temperature increases with pressure.
	2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson 14:53: But it's important to remember that the laws of physics are time reversible.
	2017-04-26: Are You a Boltzmann Brain? 00:44: He showed that the laws of thermodynamics can be explained by thinking of gas as a collection of microscopic particles in constant, random motion. 01:54: That's the second law of thermodynamics, right there. 04:01: ... universe for it to happen, so in practice we never observe the second law of thermodynamics being broken on macroscopic ... 06:48: This is just Occam's razor, or the law of parsimony-- don't add unnecessary complexity to your explanation. 00:44: He showed that the laws of thermodynamics can be explained by thinking of gas as a collection of microscopic particles in constant, random motion.
	2017-03-01: The Treasures of Trappist-1 04:12: Wein's law tells us that the 2,500 Kelvin TRAPPIST-1 star shines brightest at infrared wavelengths.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 05:19: Kepler's third law tells us this.
	2017-01-19: The Phantom Singularity 00:16: [MUSIC PLAYING] Isaac Newton's universal law of gravitation was an incredible insight when he figured it out in the late 1600s. 01:21: According to Newton's law, in order to fuel that infinite gravitational acceleration you need to get zero distance from an object's center of mass. 04:04: So, does the fact that it includes a singularity mean there's something fundamentally wrong with Newton's law of gravitation? 04:12: Well, we already know the law isn't really so universal. 04:16: ... field is too strong-- say, near a star or a black hole-- Newton's law gives the wrong answers, and we need Einstein's general theory of ... 06:47: r, the distance to the center of mass, remains in the denominator just as it was in Newton's law. 07:13: But unlike Newton's laws of gravity, the Schwarzschild metric actually tells us whether or not that infinite density is expected. 07:22: To see how, we need to look at the second singularity in this equation, a singularity that Newton's law does not contain. 04:12: Well, we already know the law isn't really so universal. 07:13: But unlike Newton's laws of gravity, the Schwarzschild metric actually tells us whether or not that infinite density is expected.
	2017-01-11: The EM Drive: Fact or Fantasy? 02:33: The law of conservation of momentum demands this. 02:56: Which is to say, this explanation breaks the law of conservation of momentum.
	2016-12-21: Have They Seen Us? 11:12: ... a slightly more advanced civilization, that's several Moore's law doublings ahead of us in various technologies, and accounting for ...
	2016-11-16: Strange Stars 09:38: Who knows what other strange denizens lurk in yet to be discovered laws of physics?
	2016-07-27: The Quantum Experiment that Broke Reality 02:13: ... from the quantized energy levels of Max Planck's black-body radiation law. ...
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 05:36: The resulting Rayleigh-Jeans law described the blackbody spectrum perfectly. 06:11: It was catastrophic because it meant that something was fundamentally wrong with the classical physics that went into the Rayleigh-Jeans law. 08:18: It became Planck's law. 08:47: The Planck constant is firmly entrenched in the Planck blackbody law. 08:59: ... it was possible to do this just by varying the constant until the Planck law matched the observed ... 09:10: ... once you know the Planck law and an object's temperature, you can calculate the Planck constant just ... 08:59: ... it was possible to do this just by varying the constant until the Planck law matched the observed ...
	2016-05-25: Is an Ice Age Coming? 13:58: ... here, but I don't think it's a speculative statement to say that the law of conservation of energy, as we learned when we studied Newtonian ... 14:43: The universe is mechanistic and its behavior results in emergent mathematical laws that allow us to model and predict its behavior. 14:51: Conservation of energy is one such law that work in flat space time. 14:43: The universe is mechanistic and its behavior results in emergent mathematical laws that allow us to model and predict its behavior.
	2016-05-18: Anti-gravity and the True Nature of Dark Energy 04:04: This thing is in a real way just Newton's law of gravitation for the whole cosmos. 11:29: See, the law of conservation of energy no longer applies in an expanding universe. 11:35: This law is a property of a Newtonian universe, in which space and time are fixed static dimensions. 13:04: A few of you suggested that Moore's Law is near its end. 13:09: ... that there's a limit to the miniaturization of silicon chips, Moore's Law for computing has been roughly consistent since around 1900, with the ... 13:34: The analogies to Moore's Law for laser power, material science, battery tech, et cetera, are also alive and well.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 06:56: The program relies very heavily on the projections of Moore's law.
	2016-04-20: Why the Universe Needs Dark Energy 11:22: And, if you choose, you can always sell your soul for the big bucks in finance, business consulting, patent law, et cetera.
	2016-04-13: Will the Universe Expand Forever? 02:58: Now this escape velocity comes right out of Newton's universal law of gravitation, which itself can be derived from the Einstein equations.
	2016-03-23: How Cosmic Inflation Flattened the Universe 11:47: It doesn't exist in the inertial reference frames for which Newton's laws are valid.
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 00:35: All of these things obey the same laws of physics and all of them are held together by gravity. 02:23: ... Universal Law of Gravitation tells us that the strength of gravity drops off with the ... 10:26: They also give us things like the Laws of Conservation of Energy and of Linear and Angular Momentum, topics that we will get to. 00:35: All of these things obey the same laws of physics and all of them are held together by gravity. 10:26: They also give us things like the Laws of Conservation of Energy and of Linear and Angular Momentum, topics that we will get to.
	2016-03-02: What’s Wrong With the Big Bang Theory? 01:06: ... we got down to that size by rewinding the laws of physics, and in particular running the math of Einstein's general ...
	2016-02-24: Why the Big Bang Definitely Happened 02:15: ... of the universe, or even just a tiny part of the universe, and run the laws of physics forward in time to predict the ... 02:24: Or run those laws backwards and predict the past. 09:21: Theories actually contain laws, and those laws are often the most well-established parts of a theory. 11:39: ... quote Lawrence Stanley, "OK, but until the discovery of gravitational waves can lower ... 02:15: ... of the universe, or even just a tiny part of the universe, and run the laws of physics forward in time to predict the ... 02:24: Or run those laws backwards and predict the past. 09:21: Theories actually contain laws, and those laws are often the most well-established parts of a theory. 02:24: Or run those laws backwards and predict the past.
	2016-01-06: The True Nature of Matter and Mass 02:20: The photons exert a force on the box, the box also exerts a force on the photons-- Newton's Third Law, which gives us the conservation of momentum.
	2015-11-25: 100 Years of Relativity + Challenge Winners! 04:12: Newton's law of universal gravitation tells us the force between two massive objects.
	2015-11-11: Challenge: Can you save Earth from a Killer Asteroid? 01:49: You'll need Newton's law of universal gravitation as well as basic mechanics and kinematics.
	2015-10-07: The Speed of Light is NOT About Light 01:46: This Galilean Relativity is an incredible insight that Isaac Newton would later codify into his Laws of Motion. 01:52: Fast forward to the 1800s-- top hats, steam trains, and mad experiments to uncover the laws of electricity and magnetism. 02:00: ... James Clerk Maxwell, scientific maestro, who weaves these laws into his eponymous equations, describing the entire electromagnetic ... 04:17: This transformation thing, it's like a mathy magic wand that you wave at your description of spacetime or your physical laws. 06:00: Under our new transformation, the laws of physics will work the same regardless of position, orientation, or velocity. 07:59: With it, we can write down one law for electromagnetism that works in all frames of reference. 08:20: For the laws of electricity and magnetism to work, we need a finite maximum cosmic speed, even without considering light. 01:46: This Galilean Relativity is an incredible insight that Isaac Newton would later codify into his Laws of Motion. 01:52: Fast forward to the 1800s-- top hats, steam trains, and mad experiments to uncover the laws of electricity and magnetism. 02:00: ... James Clerk Maxwell, scientific maestro, who weaves these laws into his eponymous equations, describing the entire electromagnetic ... 04:17: This transformation thing, it's like a mathy magic wand that you wave at your description of spacetime or your physical laws. 06:00: Under our new transformation, the laws of physics will work the same regardless of position, orientation, or velocity. 08:20: For the laws of electricity and magnetism to work, we need a finite maximum cosmic speed, even without considering light.
	2015-09-30: What Happens At The Edge Of The Universe? 07:31: Are the laws of physics, or even the number of dimensions, the same?
	2015-08-12: Challenge: Which Particle Wins This Race? 02:07: It's something called Gauss's Law.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 12:39: ... geodesics should be-- that resemble-- that basically give you Newton's laws of motion as if there were a gravitational force-- are just the pieces ...
	2015-07-08: The Leap Second Explained 00:30: Thus, in 1960, the second was redefined to be whatever would make the motions of multiple objects in the solar system fit Newton's laws of motion.
	2015-06-17: How to Signal Aliens 06:35: ... an "inertial frame." That means reexamining Newton's first and second laws and so ...
	2015-06-03: Is Gravity An Illusion? 00:54: OK, bear with me for a minute because we need to begin with some Physics 101 and Newton's laws of motion. 01:25: ... Newton's laws can't tell you whether a frame of reference is really at rest or really ... 01:34: However, interestingly, Newton's laws can tell you whether your frame of reference is really accelerating or not. 01:49: Now in Newtonian physics, inertial frames are special because Newton's second law, F equals ma, is only valid in inertial frames. 00:54: OK, bear with me for a minute because we need to begin with some Physics 101 and Newton's laws of motion. 01:25: ... Newton's laws can't tell you whether a frame of reference is really at rest or really ... 01:34: However, interestingly, Newton's laws can tell you whether your frame of reference is really accelerating or not.
	2015-04-09: How to Weigh a Fart 00:20: ... you pretend that the fart obeys the ideal gas law from high school chemistry class, which it probably does to a decent ...

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