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2022-12-14: How Can Matter Be BOTH Liquid AND Gas?

  • 15:11: ... back to the 1920’s and debate interpretations of quantum mechanics with Einstein and Schrödinger!” – well, then you’d need to learn ...

2022-11-23: How To See Black Holes By Catching Neutrinos

  • 10:17: This leads to massive amplification of the jet’s light due to Einstein stuff.

2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations?

  • 17:08: ... Yavor Tch and zomgthisisawesomelol point out that Einstein was referring to wavefunction collapse when he said "spooky action at a ...
  • 17:23: ... Einstein was referring to general wavefunction collapse, in which the ...
  • 17:37: ... Einstein then got together with Boris Podolsky and Nathan Rosen and basically ...

2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics?

  • 00:34: ... the prediction that Einstein refused to accept - the idea that two quantum systems can be entangled - ...
  • 00:47: ... “spooky action at a distance” as Einstein called it, is in seeming violation of his own theory of relativity, ...
  • 00:58: ... and Aspect achieved the rarest of feats - they proved Einstein wrong, while Zeilinger greatly advanced our understanding and ...
  • 03:46: ... Einstein thought that such hidden information must exist, while others like ...
  • 03:56: In almost every scientific debate,  physicists side with Einstein.
  • 10:35: There are two ways that the Bell inequalities could be violated without quantum entanglement being as spooky as Einstein feared.
  • 12:18: Any violation of locality still means that some sort of influence travels faster than light - the sort of spookiness that Einstein hated.
  • 13:32: This is a rare episode of Space Time in  which both Einstein and Feynman were wrong.
  • 13:38: Einstein because, one way or another,  the quantum world is indeed quite spooky.

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 04:12: ... first let’s review gravitational  lensing. Einstein’s general theory of relativity   tells us that gravity is due to ...
  • 04:36: ... galaxy cluster. If the alignment is close enough, we can see an Einstein Ring, like this   galaxy being lensed by an intervening ...
  • 10:07: ... 550 astronomical units,   and extending indefinitely, with the Einstein ring getting wider and more diffuse the further you go.   ...

2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics?

  • 02:36: ... who managed to explain  the discrepancy by including the effects of Einstein’s still-new relativity, as well as the fact that the energy levels of ...
  • 11:20: ... relativity; it’s also the relationship  between mass and energy in Einstein’s famous ...

2022-08-17: What If Dark Energy is a New Quantum Field?

  • 01:25: ... cosmological constant. This is just a static number that you can add to Einstein’s equations of general relativity to represent the fabric of space having ...

2022-07-20: What If We Live in a Superdeterministic Universe?

  • 01:55: Albert Einstein also came up with a scenario in which he tried to refute the non-realist implications of pure quantum mechanics.
  • 03:27: Measurement of one electron would influence the other in a very real way - something Einstein referred to as spooky action at a distance.
  • 05:11: This type of effect that made Einstein and company so uncomfortable.
  • 07:03: Countless Bell-type tests have been performed since, all with the same result: apparently entanglement is real and is as spooky as Einstein feared.
  • 07:52: There are ways to save realism in quantum mechanics by crossing Einstein and abandoning locality.

2022-06-15: Can Wormholes Solve The Black Hole Information Paradox?

  • 00:26: ... electromagnetism didn’t square with Galileo’s relativity led Einstein to his special   theory of relativity, from which followed ...

2022-06-01: What If Physics IS NOT Describing Reality?

  • 12:09: ... Wheeler: “whose information?”   This same question haunted Einstein. Einstein  famously once asked whether proponents of ...

2022-05-04: Space DOES NOT Expand Everywhere

  • 00:19: ... are all racing away from us, and interpreted through the lens of Einstein’s general theory of relativity, this only makes sense if all distances ...
  • 01:59: ... moving THROUGH space, but there’s a cleaner picture. Soon after Einstein finished general relativity, four scientists independently solved its ...

2022-04-20: Does the Universe Create Itself?

  • 00:59: ... desperate to maintain a physical and realist universe, including Albert Einstein himself. We’ve talked about this debate between the founders of quantum ...

2022-03-30: Could The Universe Be Inside A Black Hole?

  • 00:19: Einstein’s ridiculously successful general theory of relativity has never failed.
  • 00:36: Well it turns out that black holes and the Big Bang have more in common than vexing Einstein.
  • 06:05: It’s a white hole, and it’s a valid a solution to the Einstein equations.
  • 09:06: ... was the same that Alexander Friedmann made when he first solved the Einstein equations for the whole universe, and it’s the assumption behind the ...

2022-03-23: Where Is The Center of The Universe?

  • 02:55: As with much, it starts with Einstein.
  • 03:19: It wasn’t actually Einstein who worked this out.
  • 11:45: And you can do it without breaking Einstein’s general relativity.
  • 12:02: He sought solutions to the Einstein equation for a universe that is lumpy on the largest scales.

2022-02-10: The Nature of Space and Time AMA

  • 00:03: ... updated due to due to all of our beautiful newtonian mechanics then einstein came and changed all of it space and time became space-time due to the ...

2022-01-27: How Does Gravity Escape A Black Hole?

  • 00:35: ... 1915 Einstein presented to the world the equations behind his general theory of ...
  • 00:48: Einstein’s theory predicted the existence of the ultimate gravitational object: the black hole.
  • 01:01: ... to Einstein’s theory, any object that reaches such a density has to collapse to a ...
  • 01:21: ... Einstein built the equations of GR Equation: G_{\mu\nu} + \Lambda g_{\mu\nu} = ...
  • 03:17: First we’ll see what Einstein has to say on the matter, and then we’ll go deeper, into the speculative realm of quantum gravity.
  • 08:39: ... and this one works whether we’re talking about the classical gravity of Einstein or some deeper theory of quantum ...

2022-01-19: How To Build The Universe in a Computer

  • 09:34: ... started about the complexity  of including magnetic fields, or of Einstein’s general relativity when the gravitational field becomes very ...

2021-12-20: What Happens If A Black Hole Hits Earth?

  • 14:26: ... fields to GR so that our theory fits the data.” Well to that I’ll let Einstein respond: “It can scarcely be denied that the supreme goal of all theory ...

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... the fact that massive bodies bend the paths of light according to einstein's theory of general relativity so when you look out there you see you ...

2021-11-17: Are Black Holes Actually Fuzzballs?

  • 00:20: ... theory - fuzzballs - are perhaps even weirder than the regular type Einstein’s general theory of relativity tells us that if the density of matter is ...

2021-11-10: What If Our Understanding of Gravity Is Wrong?

  • 00:09: New work is taking another  shot at that Einstein guy.
  • 02:52: ... Einstein found that Newtonian gravity  breaks down when the gravitational ...
  • 03:08: But Einsteinian gravity looks exactly like Newtonian gravity when gravitational fields get weak.
  • 03:15: But what if Einstein missed something?
  • 08:35: ... Einstein’s description, the gravitational  field is what we call a ...

2021-11-02: Is ACTION The Most Fundamental Property in Physics?

  • 05:52: ... start with Einstein’s General Theory of Relativity, which, as we’ve discussed before, ...
  • 07:09: ... gives equations of motion that are valid even in the shifting frames of Einstein’s relativity. And we also start to learn something about the nature of the ...

2021-10-20: Will Constructor Theory REWRITE Physics?

  • 00:00: ... people behind the greatest leaps in physics - Einstein, Newton, Heisenberg, all had the uncanny ability to see the fundamentals ...
  • 01:43: ... and so on from two master theories: quantum mechanics and Einstein’s general ...
  • 10:42: ... Einstein’s general theory of relativity came from asking what were the inevitable ...

2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light

  • 05:22: Now, our old pal Professor Einstein is not a fan of faster-than-light motion.
  • 07:45: ... time relied on the Schrodinger equation, which doesn’t incorporate Einsteins’s special theory of relativity and so has no speed limit baked into ...

2021-09-07: First Detection of Light from Behind a Black Hole

  • 11:33: ... measuring the mass of the black hole - 30 million Suns - to verifying Einstein’s general theory of ...

2021-08-10: How to Communicate Across the Quantum Multiverse

  • 17:57: ... rabbit holes. Which apparently I’m never going to learn. Of course as Einstein said, "The definition of insanity is doing the same thing over and over ...

2021-07-07: Electrons DO NOT Spin

  • 02:25: ... experiment with the iron cylinder is called  the Einstein de-Haas effect, first performed by, well, Einstein and de-Haas in 1915. ...
  • 04:40: ... that plays into the conservation of angular momentum like  in the Einstein de-Haas effect, and it also gives electrons a magnetic field. An ...
  • 08:28: ... fix of the Schrodinger equation - in this case to make it work with Einstein’s special theory of relativity - something we’ve discussed  before. ...

2021-06-23: How Quantum Entanglement Creates Entropy

  • 05:55: ... - this mysterious connection between quantum particles that Einstein called   “spooky action at a distance”. As a bit of a  ...

2021-06-16: Can Space Be Infinitely Divided?

  • 05:45: ... continue our gerdankenexperiment,  now adding two key ideas from Einstein:   first that mass and energy are equivalent, as expressed by the most ...
  • 06:02: ... creates what we call effective mass, according to Einstein’s famous equation. The resulting   gravitational field changes ...
  • 10:55: ... space on this scale. The nature of   space is defined by Einstein’s general relativity, and GR breaks down at the Planck scale ...

2021-05-25: What If (Tiny) Black Holes Are Everywhere?

  • 00:41: At least, that’s the black hole as it appears in the mathematics of Einstein’s general theory of relativity.

2021-05-11: How To Know If It's Aliens

  • 16:32: ... WIMP - namely wearing interacting, massive, and particle-like. Fun fact: Einstein, along with Nathan Rosen, tried to explain particles as gravitational ...

2021-04-21: The NEW Warp Drive Possibilities

  • 00:00: That Einstein guy was a real bummer for our hopes of a star-hopping, science-fiction-y future.
  • 00:12: But Einstein also gave us a glimmer of hope.
  • 00:31: In 1915, Albert Einstein’s general theory of relativity revealed that the fabric of space and time is mutable and dynamic.
  • 01:27: Space-warp drives, time-warp drives, and eventually just warp drives became an increasingly popular way of breaking Einstein’s rules.
  • 01:34: ... - and Star Trek inspired the very first real warp field solution to the Einstein field ...
  • 02:25: Einstein’s speed limit doesn’t directly say that nothing can travel faster than light.
  • 03:29: It’s a sp acetime geometry that is a valid solution to the equations general theory of relativity. The Einstein Field Equation.
  • 03:54: The Alcubierre warp field may be a valid solution to the Einstein field equations, but that doesn’t mean it’s physically possible.
  • 04:31: ... combat this, we have a set of energy conditions that go alongside the Einstein field equations that are meant to restrict the allowable energy ...
  • 06:51: These guys propose a general definition for warp fields not tied to a particular solution to the Einstein field equations.
  • 08:54: OK, let’s move on to the second paper by Erik Lentz: “Breaking the Warp Barrier: Hyper-Fast Solitons in Einstein-Maxwell-Plasma Theory”.
  • 09:19: He does this by exploring a broader family of solutions to the Einstein field equations than previous studies.
  • 12:18: Einstein and the universe appear to be trolling us - alternately inspiring and crushing our hopes for a star-hopping future.
  • 12:37: They’ll continue to try to “make it so” by exploring Einstein’s theory - hoping to build starship, but in the process learning how our universe works.

2021-04-13: What If Dark Matter Is Just Black Holes?

  • 00:44: ... are trying to find holes in Einstein’s theory of gravity - the general theory of relativity - that might ...

2021-04-07: Why the Muon g-2 Results Are So Exciting!

  • 00:47: In fact, it doesn't play nice with Einstein's entire theory of gravity, which itself is clearly right in its own way.

2021-03-09: How Does Gravity Affect Light?

  • 00:28: That fact is guaranteed by Einstein’s general theory of relativity.
  • 02:14: ... is Einstein’s great insight that there’s no experiment that can distinguish between ...
  • 05:02: ... let’s tackle an even trickier problem - the solving of which shot Einstein to his international fame - the deflection of the path of light by ...
  • 07:16: Einstein was in the business of overturning the ideas of Newton, so it’s not surprising that he turns to one of Newton’s great rivals.
  • 09:34: But this is exactly what Einstein did.
  • 11:21: Einstein used this approach to calculate the deflection expected when light passes a massive object.
  • 11:35: And Einstein’s deflection angle was famously verified by Sir Arthur Eddington, who voyaged to the west coast of Africa to watch a solar eclipse.
  • 11:52: So I guess the question I’d be asking at this point is why did Einstein’s calculation even work.
  • 12:08: ... you solve Einstein’s equations in a different way, you can show that gravity is due to a ...

2021-02-24: Does Time Cause Gravity?

  • 00:34: ... - it follows as surely as 1+1=2 if we accept the two axioms of Einstein’s relativity theory: that the speed of light is constant for all ...
  • 03:49: In Einstein’s relativity you have to remember that time and space are not independent of each other.
  • 06:29: ... the same favorable exchange when we try to convert mass into energy via Einstein’s most famous equation, E=mc^2 - the speed of light is the exchange rate, ...
  • 07:56: In fact, the imaginary paths of light rays were one the most important tools that helped Einstein develop both special and general relativity.

2021-02-10: How Does Gravity Warp the Flow of Time?

  • 00:21: Albert Einstein really enjoyed imagining people falling off buildings.
  • 01:13: Einstein had his happy thought in 1907, a couple of years after he started his scientific revolution with the special theory of relativity.
  • 03:35: Einstein also had help and built on prior and contemporary wisdom to develop it.
  • 03:48: Einstein’s thought laboratory - his gedankenlab - was filled with many incredible imaginary devices, but one of his favorites was the photon clock.

2021-01-26: Is Dark Matter Made of Particles?

  • 15:11: ... to decelerate and then accelerate again to turn around, and according to Einstein’s equivalence principle, acceleration is fundamentally the same as ...
  • 16:23: And a final thought from Sebastian Elytron, who expresses surprise that apparently Einstein was a real person.

2021-01-19: Can We Break the Universe?

  • 00:00: That Einstein guy had some pretty wacky ideas.
  • 00:09: ... back in 1905, when Einstein was just getting started - he was already rocking our understanding of ...
  • 12:05: ... sense of this deeply strange, but unfailingly self-consistent theory of Einstein’s ...

2021-01-12: What Happens During a Quantum Jump?

  • 04:27: The most famous quote on the not-Copenhagen side was from Albert Einstein - “God does not play dice with nature”.
  • 10:33: I suspect both Schrodinger and Einstein would agree.

2020-12-15: The Supernova At The End of Time

  • 05:27: ... failed to incorporate the effects of Albert Einstein’s relativity theory, which predicted that the world looks very different ...

2020-11-18: The Arrow of Time and How to Reverse It

  • 00:24: ... from the subatomic realm of quantum mechanics to the cosmic realm of Einstein’s general relativity. But if time doesn’t have a preferred direction in ...

2020-11-11: Can Free Will be Saved in a Deterministic Universe?

  • 00:25: ... determinism in the context of the block universe idea that we get from Einstein's ...

2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time

  • 00:00: ... theorem   is much deeper - it leads us to the limits Einstein’s  great theory and to the origin of the ...
  • 00:34: ... told us.   In 1915, Newtonian gravity was superseded by Einstein’s general theory of relativity.   But that wasn’t the end of ...
  • 01:17: ... Schwarzschild solved the equations of general relativity soon after Einstein published them,   revealing that a sufficiently dense ball of ...
  • 03:18: ... figured out how to describe a rotating black   hole in Einstein’s theory. In it, the central point of infinite gravity is spun out ...
  • 03:38: ... that black hole singularities   were utterly unavoidable in Einstein’s theory. Penrose’s singularity paper is   deceptively short - just a ...
  • 04:35: ... of minutes. Basically,   Penrose showed that according to Einstein’s theory plus a couple of assumptions,   black holes must contain ...

2020-10-20: Is The Future Predetermined By Quantum Mechanics?

  • 00:00: - Einstein's Special Theory of Relativity combines space and time into one dynamic unified entity, spacetime.
  • 00:31: In a block universe of Einstein's relativity, there's no way to cleanly define the present and so no way to cleanly separate the future from the past.
  • 12:42: In Einstein's relativity, the definition of simultaneous events is well, relative.
  • 15:32: Guilherme Marquesani takes issue with my characterization of Einstein as the smartest man in the block universe.
  • 15:44: Also, I'm pretty sure Einstein was another Renegade from the Citadel of Rick's.

2020-10-13: Do the Past and Future Exist?

  • 05:51: Einstein says otherwise.
  • 05:53: ... his special theory of relativity, Einstein showed that there’s no absolute way to define whether two events happen ...
  • 08:29: ... that’s the effect of Einstein’s special relativity - space and time tilt into each other, so that ...

2020-09-21: Could Life Evolve Inside Stars?

  • 12:50: ... century were in part driven by 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

  • 02:41: Einstein’s equations of general relativity give even better precision than Newton’s law - perhaps perfect precision - in their description of gravity.
  • 03:13: Ptolemy, Copernicus, Kepler, Newton, Einstein - each followed their own sense of mathematical beauty in this long quest to understand gravity.
  • 06:35: The step from Kepler to Newton suggests so, but then why does complexity seem to increase when you go one level deeper from Newton to Einstein?
  • 06:45: ... is probably a good time for a quote from Einstein himself: “The supreme goal of all theory is to make the irreducible ...
  • 07:12: One of Einstein’s contemporaries, and one of the very few that might be considered his intellectual peer, seems to have disagreed.
  • 07:49: He sought to develop a quantum mechanical wave equation that agreed with Einstein’s special relativity.
  • 09:39: And then there’s Einstein’s field equations of general relativity.
  • 10:01: ... couple of years after Einstein presented his general theory of relativity - Weyl found a simple, ...
  • 10:46: The first compellingly beautiful aspect of string theory is that gravity, in the form of the Einstein field equations - automatically emerged from it.

2020-09-01: How Do We Know What Stars Are Made Of?

  • 00:39: A hundred years ago, we were starting to plumb the deepest mysteries of the universe with Einstein’s relativity and with quantum theory.
  • 01:43: ... who recounted his recent solar eclipse expedition in which he verified Einstein’s new general theory of ...

2020-08-17: How Stars Destroy Each Other

  • 14:41: Well, as Einstein said: The eternal mystery of the world is its comprehensibility.
  • 14:46: So if you’re comprehending Space Time does that make you Einstein?

2020-08-10: Theory of Everything Controversies: Livestream

  • 00:00: ... copy right here it's um my favorite beach reading and more recently einstein's unfinished revolution the search for what lies beyond the quantum lee ...

2020-07-28: What is a Theory of Everything: Livestream

  • 00:00: ... in the universe and that's a fantastic theory of course developed by einstein and you know the mathematical properties developed by some other ...

2020-07-20: The Boundary Between Black Holes & Neutron Stars

  • 01:04: ... the shape of the gravitational waveform, and based on calculations using Einstein’s general theory of relativity, the masses of those bodies were ...

2020-06-30: Dissolving an Event Horizon

  • 10:12: As Einstein taught us, mass and energy are equivalent.

2020-06-15: What Happens After the Universe Ends?

  • 04:54: Now in Einstein’s universe it’s not quite that simple.

2020-05-27: Does Gravity Require Extra Dimensions?

  • 01:28: ... Einstein's general theory of relativity has a perfect track record predicting the ...
  • 01:42: And deviations from Newton’s description may point the way to an understanding deeper than Einstein’s.

2020-05-18: Mapping the Multiverse

  • 00:09: ... in english: when you solve Einstein’s equations of general relativity for a rotating black hole, the universe ...
  • 14:05: ... luminiferous aether, and so doing paved the way for the acceptance of Einstein's ...

2020-05-11: How Luminiferous Aether Led to Relativity

  • 01:09: ... The death of the aether helped open the way for the acceptance of Einstein’s theory of ...
  • 11:42: ... that brings us to Einstein. The constancy of the speed of light and the Lorentz transformation are ...
  • 12:25: ... However the general concept of the aether sort of has an afterlife. Einstein talked about the “new aether” as the medium of the gravitational field, ...
  • 13:18: ... appears to have believed in the luminiferous aether until the end. When Einstein visited Michelson on his deathbed in 1931 Michelson's daughter begged ...

2020-05-04: How We Know The Universe is Ancient

  • 03:09: ... The recession of the galaxies makes perfect sense in the context of Einstein’s then-new general theory of ...
  • 03:24: ... Russian cosmologist Alexander Friedmann solved Einstein’s equations and found the possibility of a universe that could change in ...
  • 16:15: ... can write down a solution to the Einstein equations in which the wormhole throat is short, and it has no ...

2020-04-28: Space Time Livestream: Ask Matt Anything

  • 00:00: ... theory yeah yeah he's amazing the theorists theorists they call him Einstein would always carry around his version of Paul Dirac's textbook on ...

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 00:23: ... 1915, Karl Schwarzschild discovered a solution to Einstein’s brand new equations of general relativity - a solution that we now ...
  • 01:09: ... 1935, Albert Einstein, along with Nathan Rosen, expanded on Flamm’s idea - but not into a ...
  • 01:52: ... turns out that this is almost certainly NOT what particles are, but the Einstein-Rosen paper inspired others to take the wormhole seriously - and inspired the ...
  • 02:08: ... Archibald Wheeler, along with his ex-student Bob Fuller, realized that Einstein & Rosen’s bridge did not necessarily have to connect parallel layers ...
  • 04:50: ... paths are always at a steeper angle. The strange extra layer that Einstein and Rosen discovered is represented as a mirror reflection to our ...
  • 09:17: ... that are placed on allowable distributions of mass and energy in Einstein’s equation in order for those equations to make physical sense. But these ...
  • 13:26: ... example, Leonard Susskind and Juan Maldecina have speculated that the Einstein-Rosen bridge may explain quantum entanglement - itself first described by ...

2020-03-31: What’s On The Other Side Of A Black Hole?

  • 01:53: ... of algebra derived by Karl Schwarzschild just a couple of months after Einstein published his general theory of relativity. It allows us to calculate ...
  • 07:32: ... horizons and emerge in the mirror universe. You’ve just traversed an Einstein-Rosen bridge - a wormhole. We’ll come back to the detailed physics of ...
  • 10:58: ... hole isn’t likely to be real, there are intriguing possibilities. That Einstein-Rosen bridge can potentially be made to lead to different parts of THIS ...

2020-03-24: How Black Holes Spin Space Time

  • 00:21: ... months after Einstein presented his complete general theory of relativity in 1915, a young ...
  • 02:36: ... importance of spin in black holes, it took nearly half a century before Einstein’s equations were solved for the rotating case. That was by Roy Kerr in ...
  • 05:14: ... Probe B measured the Earth’s frame dragging and it was exactly as Einstein’s theory predicted - incredibly weak in Earth’s case. But in the case of a ...

2020-03-16: How Do Quantum States Manifest In The Classical World?

  • 04:28: ... most famous entanglement experiment is the one that Einstein came up with to demonstrate an apparent absurdity predicted by pure ...
  • 05:32: ... influence is transferred potentially faster than light. This is what Einstein called spooky action at a distance, and we now know that this is a very ...

2020-02-18: Does Consciousness Influence Quantum Mechanics?

  • 08:20: ... role of the conscious mind - and vigorously defended himself after Einstein accused him of introducing mysticism into ...

2020-02-03: Are there Infinite Versions of You?

  • 12:29: Ilavenya rightly points out that no nice analytical solutions to the 3-body problem exist in general relativity - Einstein's modern theory of gravity.

2020-01-13: How To Capture Black Holes

  • 00:59: ... black hole mergers themselves were not so surprising. Einstein’s general relativity predicted gravitational waves and astrophysics ...

2019-12-17: Do Black Holes Create New Universes?

  • 12:42: ... subjects like relativity. In this course you’ll begin by understanding Einstein’s postulates and the Lorentz transformations, and as your knowledge ...

2019-12-09: The Doomsday Argument

  • 16:05: ... these are valid geometries for spacetimes that can be constructed within Einstein's general relativity, it's not clear how such a universe would form, and ...

2019-12-02: Is The Universe Finite?

  • 02:59: Albert Einstein’s general theory of relativity allows for three simple geometries for our universe.

2019-10-21: Is Time Travel Impossible?

  • 00:38: Or so we thought until Einstein came along.
  • 07:05: One example is the Tipler cylinder, conceived by Frank Tipler based on a solution to the Einstein equations by Willem van Stockum.

2019-10-15: Loop Quantum Gravity Explained

  • 00:28: To connect quantum physics with Einstein’s general theory of relativity.
  • 08:07: In the 1950s Einstein himself tried to rewrite general relativity in terms of these parallel transport vector connections, but the result was a mess.
  • 16:29: ... the answer lies in the Einstein field equation of general relativity That equation says that the amount ...

2019-10-07: Black Hole Harmonics

  • 09:38: And that brings us to the last, and perhaps coolest application of this technique – testing Einstein.
  • 10:19: ... and the time for the decay of those oscillations agrees perfectly with Einstein’s ...
  • 11:00: But for now, Einstein reigns supreme.

2019-08-19: What Happened Before the Big Bang?

  • 00:04: That is as long as you define 'The Big Bang' as the universe's early hot dense expanding state that's well described by Einstein's equations.
  • 10:51: ... receding galaxies could be explained by an expanding universe and solved Einstein's equations to show ...

2019-08-06: What Caused the Big Bang?

  • 02:26: First up, the equations of Einstein's general theory of relativity.
  • 03:23: ... is that if the vacuum of space has a constant energy density, then Einstein's equations end up having a term that we call the cosmological constant - ...
  • 04:38: To see how this could happen we need to move beyond Einstein's general relativity.

2019-07-18: Did Time Start at the Big Bang?

  • 00:25: ... the retreating galaxies by Edwin Hubble and Vesto Slipher, combined with Einstein's - then - brand-new general theory of relativity, revealed that our ...
  • 01:56: ... existence In fact, There's powerful evidence that we should not rewind Einstein's equations that far, at least without introducing some very new physics ...
  • 06:02: ... if you're going forward No, you have to think about time in the way Einstein Intended there is no universal clock time is relative Clocks are ...
  • 07:22: ... on how you want to think about it The point is that in the pure Einsteinian picture There is no before the Big Bang because no time line in this ...
  • 08:04: from the pure Einsteinian point of view It's meaningless to ask what happened before the Big Bang or after reaching the black hole Center?

2019-05-09: Why Quantum Computing Requires Quantum Cryptography

  • 16:30: The Inebriati logs the following: Day 37,736: Einstein still appears to be right about general relativity.

2019-05-01: The Real Science of the EHT Black Hole

  • 08:55: ... case with the addition of the warped spacetime of a black hole using Einstein’s theory of general ...
  • 10:17: ... couple of years ago, the black hole looks just like we predict based on Einstein’s general theory of ...
  • 10:33: ... then when black holes emerged from Karl Schwarzschild’s solution to the Einstein equations, they seemed like a deep abstraction – a prediction that ...
  • 10:54: ... team – finally hits us with visceral reality of the black hole, Einstein’s wildest prediction and the strangest object in all of space ...

2019-04-24: No Dark Matter = Proof of Dark Matter?

  • 00:03: ... doesn't just modify Newton's gravity but also requires modification of Einstein's general relativity over the years various efforts have been made to ...

2019-04-03: The Edge of an Infinite Universe

  • 02:29: At least the three basic types described by Einstein’s general theory of relativity.
  • 03:17: In GR this is Minkowski space, after Hermann Minkowski, teacher and colleague of Albert Einstein’s.

2019-03-28: Could the Universe End by Tearing Apart Every Atom?

  • 00:25: ... energy density with the cosmological constant in the equations of Einstein's general theory of relativity but what if dark energy is not constant ...
  • 01:55: ... let's do a quick refresher on how dark energy works in the language of Einstein's general relativity I say refresher because we spent a whole playlist ...
  • 03:05: ... which depends on how much stuff there is in the universe because this is Einstein's gravity not Newton's, gravity is influenced by mass and energy density ...

2019-03-20: Is Dark Energy Getting Stronger?

  • 02:13: Mathematically we represent a constant vacuum energy with Einstein’s cosmological constant – or Lambda.

2019-02-07: Sound Waves from the Beginning of Time

  • 12:20: They also confirm the dark energy behaves just as is predicted by Einsteins cosmological constant.
  • 16:08: In so-called bimetric gravity, you can have positive and negative masses, but each is described by its own set of Einstein field equations.

2019-01-30: Perpetual Motion From Negative Mass?

  • 05:47: ... only approximation of a much more complete description of gravity: Einstein’s general theory of ...
  • 10:58: ... geodesics of general relativity – the paths carved into the geometry of Einstein’s spacetime – are the GR analogs of Newton’s second law and give the ...

2019-01-09: Are Dark Matter And Dark Energy The Same?

  • 02:25: According to Einstein’s general theory of relativity, any such positive energy produces an inward-pulling gravity.
  • 02:47: That’s the solution to the Einstein equations that tells you the rate of acceleration of the expansion of the universe.
  • 03:34: In Einstein’s equations and the Friedmann equations, that constant energy density is represented by the cosmological constant, or Lambda.

2018-12-20: Why String Theory is Wrong

  • 00:21: [intro music] Hermann Weyl once said, "If I have to choose between beauty and truth, I choose beauty." It was in reaction to a rebuke by Einstein.
  • 00:35: Weyl had tried to explain electromagnetism by imposing on Einstein's general theory of relativity.
  • 00:41: ... very first gauge symmetry -- Weyl invariance Einstein pointed out that the proposal led to some absurd results, and so the ...
  • 02:27: In 1919, not long after Einstein published his great theory of gravity, Theodor Kaluza discovered something strange.
  • 02:43: ... that in the right sort of 5-D space-time, you can separate the resulting Einstein equations into a 4-D component that looks exactly like the familiar ...
  • 03:18: Einstein himself was supposedly jubilant at the idea -- a rather better reaction than was received for the electromagnetism of poor old Hermann Weyl.

2018-11-07: Why String Theory is Right

  • 06:36: A while ago, we talked about Paul Dirac developed a wave equation for the electron that took into account Einstein's special theory of relativity.
  • 09:43: Hermann Weyl actually came up with this symmetry right after Einstein proposed his general theory of relativity.
  • 11:44: ... of a black hole, then it looks just like the gravitational field in Einstein's ...

2018-10-31: Are Virtual Particles A New Layer of Reality?

  • 05:18: ... quantum numbers like charge and spin, but they don't need to obey Einstein's relationship between energy mass and ...

2018-10-03: How to Detect Extra Dimensions

  • 04:21: But even there, Einstein's general relativity describes gravity perfectly with three spatial dimensions.

2018-09-20: Quantum Gravity and the Hardest Problem in Physics

  • 00:34: First, Einstein's relativity utterly changed the way we think about space, time, motion, and gravity.
  • 01:41: General relativity, GR, is Einstein's great theory of gravity.
  • 11:27: Generations of physicists, starting with Einstein himself, spent their lives trying to fix this to unite quantum mechanics and general relativity.

2018-09-05: The Black Hole Entropy Enigma

  • 00:40: At least they are inevitable according to the equations of Einstein's general theory of relativity.

2018-07-18: The Misunderstood Nature of Entropy

  • 00:54: ... Einstein said that "the thermodynamics that encapsulates the second law is the ...
  • 09:56: The inevitability of the rise of entropy is as fundamental as counting, that's why Einstein and Eddington were so sure of it.

2018-07-11: Quantum Invariance & The Origin of The Standard Model

  • 02:03: Newton's laws of motion and gravity, Maxwell's equations for electromagnetism, Einstein's general relativity, and of course, the standard model.
  • 09:03: First, we need to upgrade the Schrodinger equation to the Dirac equation so it works with Einstein's special relativity.

2018-07-04: Will A New Neutrino Change The Standard Model?

  • 13:24: One minute I'm learning the constellations or Einstein quotes to impress my friends, and next, well, it's a long, sad down spiral to where I am today.

2018-06-20: The Black Hole Information Paradox

  • 05:27: ... a slight modification of general relativity called Einstein-Cartan theory, it's predicted that the formation of a rotating black hole gives ...
  • 11:44: Einstein's general theory of relativity reveals them to be regions of frozen time and cascading space.
  • 11:50: But the first hint of the existence of black holes appeared long before Einstein.

2018-06-13: What Survives Inside A Black Hole?

  • 03:24: In Einstein's general theory of relativity, we think of the gravitational field as curvature in the fabric of spacetime.
  • 08:52: In Einstein's general relativity, a spinning mass drags the fabric of space time around with it in a phenomenon known as frame dragging.

2018-05-23: Why Quantum Information is Never Destroyed

  • 12:59: When she did publish it, Einstein supposedly remarked that he had no idea that anyone could think about gravity in such general ways.

2018-05-16: Noether's Theorem and The Symmetries of Reality

  • 01:03: When it was published in 1915, Einstein's general theory of relativity opened as many questions as it answered.
  • 04:35: See, Einstein's description of gravity reveals the dimensions of space and time to be dynamic and changeable.
  • 05:08: But in Einstein's universe, energy conservation is only valid as a special case.
  • 09:18: Einstein also called her a genius.

2018-04-18: Using Stars to See Gravitational Waves

  • 02:09: Perhaps these gravitational waves signals were amplified by another phenomenon predicted by Einstein's general relativity, gravitational lensing.
  • 08:40: ... Einstein was able to derive his general theory of relativity, which predicted the ...
  • 08:56: ... mastering Newtonian gravity is also your next step toward understanding Einstein's view of ...

2018-04-04: The Unruh Effect

  • 01:57: Einstein taught us that an object without mass, like a photon, can only travel at the speed of light and no slower.
  • 09:58: According to Einstein's equivalence principle, remaining stationary in a gravitational field is equivalent to acceleration in free space.

2018-03-15: Hawking Radiation

  • 00:34: ... PLAYING] Soon after Einstein revealed his great general theory of relativity in 1915, physicists ...

2018-02-14: What is Energy?

  • 10:53: ... actually, conservation of energy is generally invalid in the context of Einstein's general theory of relativity due to the potential time evolution of ...

2017-11-29: Citizen Science + Zero-Point Challenge Answer

  • 05:15: But there's also Einstein at Home, which searches for LIGO gravitational wave data for signals produced by rotating neutron stars.

2017-11-02: The Vacuum Catastrophe

  • 04:57: Einstein's theory tells us that any form of energy produces gravity, and what matters is the absolute amount of energy, not relative deviations.

2017-10-04: When Quasars Collide STJC

  • 13:23: Wait, we're summing over the superscript mu in gamma as per the Einstein summation convention.
  • 13:30: Is-- is Einstein out the window now?

2017-08-30: White Holes

  • 00:05: Lurking in the depths of the mathematics of Einstein's general relativity is an object even stranger than the mysterious black hole.
  • 00:37: ... the idea first emerged from Einstein's general theory of relativity, physicists wondered how seriously to take ...
  • 02:31: ... a few months after Einstein published his general theory of relativity, Karl Schwarzschild solved ...
  • 12:05: ... on the other side of the black hole, accessible through what we call an Einstein-Rosen Bridge, better known as a ...

2017-08-10: The One-Electron Universe

  • 04:58: In a quantum field theory that's consistent with Einstein's special relativity, all particles must be symmetric under what we call CPT transformation.

2017-07-26: The Secrets of Feynman Diagrams

  • 05:41: And they obey Einstein's mass-energy equation.
  • 05:51: They sit on the shell structure you get when you plot Einstein's equation of energy, momentum, and mass.

2017-07-07: Feynman's Infinite Quantum Paths

  • 08:16: That means it treats space and time symmetrically and so works very naturally with Einstein's theory of special relativity.

2017-06-28: The First Quantum Field Theory

  • 04:08: This is exactly how light behaves, as was first realized by Max Planck and proved by Einstein.
  • 05:07: Basically, the Schrodinger equation is incompatible with Einstein's relativity.
  • 13:44: In fact, Schrodinger followed the same approach, starting with Einstein's mass energy momentum equation.

2017-06-21: Anti-Matter and Quantum Relativity

  • 00:16: Einstein's theory of special and general relativity had changed forever the way we think about motion, space, and time.
  • 00:50: By the late 1920s, Einstein and Planck had already shown that light is a particle, as well as a wave.
  • 01:40: First and most obvious, the Schrodinger equation is totally incompatible with Einstein's relativity.
  • 04:54: He wrote down Einstein's famous equation, E equals mc squared, but in its full form, including momentum.

2017-03-29: How Time Becomes Space Inside a Black Hole

  • 02:56: This comes from Karl Schwarzschild's solution to the Einstein field equations, the very first accurate description of a black hole.

2017-03-22: Superluminal Time Travel + Time Warp Challenge Answer

  • 02:16: Einstein showed us that there is no universal clock.

2017-02-02: The Geometry of Causality

  • 00:15: ... we peer deeper into Einstein's theory to find that the immutable ordering of cause and effect emerges ...
  • 01:04: First, let's recap a little bit of Einstein's special theory of relativity.

2017-01-19: The Phantom Singularity

  • 03:39: So you're saying Einstein is wrong?
  • 03:44: Actually, Einstein himself agreed on this point.
  • 04:16: ... star or a black hole-- Newton's law gives the wrong answers, and we need Einstein's general theory of relativity, which is the far more complete theory of ...
  • 04:45: ... what you get when you solve the delightfully complicated Einstein field equations for the simple case of a spherically symmetric mass in ...
  • 11:19: Actually, Einstein's theory and the Schwarzschild solution that is derived from it suggests it must exist.
  • 11:34: ... to better understand why the central infinity is unavoidable in Einstein's theory, we have to go back to that coordinate shift at the event ...

2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer

  • 04:41: ... studies will be powerful tests of whether they behave as predicted by Einstein's general theory of relativity or whether there are tantalizing ...
  • 10:36: In Einsteinian terms, spacetime is flat within the sphere.

2016-12-08: What Happens at the Event Horizon?

  • 01:07: ... radiation or black hole rotational growth, the simplest black hole of Einstein's general theory of relativity-- purely gravitational, static, and ...
  • 10:47: ... to a parallel universe on the other side of untraversable wormhole, the Einstein-Rosen ...
  • 12:02: It even takes you through the beginnings of Einstein's general relativity.

2016-11-30: Pilot Wave Theory and Quantum Realism

  • 03:07: Einstein famously hated the idea of fundamental randomness.

2016-11-16: Strange Stars

  • 00:55: Einstein's general theory of relativity tells us that the core of a dead star must collapse under its own incredible weight.

2016-11-09: Did Dark Energy Just Disappear?

  • 04:14: ... the cosmological constant, written as lambda, is the thing you add to Einstein's equations of general relativity to give the anti-gravitational effect of ...

2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate

  • 02:22: On the other hand, Albert Einstein insisted on an objective reality, a reality independent of our observation of it.
  • 02:40: ... an effort to demonstrate the silliness of Bohr's idea, Einstein along with Doris Podolsky and Nathan Rosen proposed a quantum scenario ...
  • 03:05: This is fundamental to Einstein's relativity, which tells us that the chain of cause and effect can't propagate any faster than the speed of light.
  • 03:13: The Einstein Podolsky Rosen, or EPR, paradox introduces one of the most mysterious ideas in quantum mechanics-- quantum entanglement.
  • 04:14: Einstein et al thought this was very silly.
  • 04:31: The argument between Bohr and Einstein felt a bit philosophical at the time.
  • 06:00: ... one, if Einstein was right, imagine the response of each particle to all possible spin ...
  • 07:07: This is exactly the spooky action at a distance that made Einstein so uncomfortable.
  • 07:13: ... so-called Bell inequalities, that we'd expect to see in the case that Einstein was right and quantum mechanics needs local hidden ...
  • 09:09: Are babies really better at quantum mechanics than Einstein?
  • 09:40: That sounds blasphemous to anyone who accepts Einstein's theory of relativity.
  • 10:41: ... example, entangled particles may be dimensionally connected by Einstein-Rosen bridges, wormholes that allows instantaneous contact even between great ...

2016-08-03: Can We Survive the Destruction of the Earth? ft. Neal Stephenson

  • 11:02: Well, Einstein would say they can't-- God, dice, nature, et cetera.

2016-07-27: The Quantum Experiment that Broke Reality

  • 02:13: ... indivisible little bundles of electromagnetic energy called "photons." Einstein demonstrated this through the photoelectric effect but his clue came ...

2016-06-22: Planck's Constant and The Origin of Quantum Mechanics

  • 09:23: As usual, it took Albert Einstein to fully understand the physics behind Planck's strange quantized vibrations.
  • 09:31: Einstein realized that it's actually light that is quantized.
  • 09:52: ... discovery was the clue Einstein needed to hypothesize the existence of the photon-- part wave, part ...
  • 10:09: Einstein proved this through the photoelectric effect.
  • 11:42: OK, a lot of you wanted to know why it is that the Einstein cross is a cross rather than a full ring.
  • 12:05: We call that an Einstein ring.
  • 13:01: Then you'll see an Einstein ring.
  • 13:03: There are some cases where you see four individual quasar images connected by an Einstein ring.
  • 13:10: That Einstein ring is actually the galaxy that hosts the quasar.

2016-06-15: The Strange Universe of Gravitational Lensing

  • 01:27: ... Einstein's general theory of relativity describes the real universe as a flexible, ...
  • 02:33: The deflection angle was exactly what Einstein's theory predicted.
  • 02:37: This particular confirmation of general relativity was the one that shot Einstein to his great fame.
  • 03:06: And Einstein originally felt that it would be acute but subtle, and not particularly relevant phenomena.
  • 04:51: This is the Einstein Cross, an extremely luminous distant quasar powered by a supermassive black hole feeding on its surroundings.
  • 07:36: Despite Einstein's pessimism, gravitational lensing has become an important staple in the astronomer's toolkit.

2016-05-18: Anti-gravity and the True Nature of Dark Energy

  • 00:19: ... episodes ago, I asked you to take a wild ride with me into the heart of Einstein's general theory of relativity and its description of the vaster of scales ...
  • 06:26: This was actually Einstein's motivation for adding the cosmological constant in the first place.

2016-05-11: The Cosmic Conspiracy of Dark Energy Challenge Question

  • 02:16: ... the Einstein field equations and in the Friedmann equations that are derived from ...

2016-04-27: What Does Dark Energy Really Do?

  • 00:16: ... we talked about how the fate of the universe can be described using Einstein's general theory of relativity via the Friedmann ...

2016-04-20: Why the Universe Needs Dark Energy

  • 00:08: ... the existence of a strange influence called "dark energy." [THEME MUSIC] Einstein's general theory of relativity allows us to describe the behavior of the ...
  • 00:35: ... To truly understand dark energy, we're glimpsing into the workings of Einstein's theory on a cosmic ...
  • 06:26: But when we tried to describe the universe by reducing the Einstein field equations into the Friedmann equations, we missed something.
  • 06:40: ... very same addition to the Einstein field equations that can describe cosmic inflation can also fix this ...

2016-04-13: Will the Universe Expand Forever?

  • 00:12: Yet the fact that Einstein's theory allows us to learn the answer to this question is incredible.
  • 00:19: ... MUSIC] Soon after Albert Einstein proposed his general theory of relativity, industrious physicists-- and, ...
  • 01:33: At the heart of general relativity are the Einstein field equations, which look like this.
  • 01:48: G is the Einstein tensor.
  • 02:16: ... gravity from a Newtonian perspective-- as a force, rather than as an Einsteinian spacetime ...
  • 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.
  • 04:09: By solving the Einstein field equations for the whole universe, of course.
  • 04:26: ... galaxies, the resulting smooth universe lets us reduce those 10 Einstein equations to only two relationships, called the Friedmann equations, ...

2016-03-23: How Cosmic Inflation Flattened the Universe

  • 06:48: Actually, Einstein came up with the exact mathematical description that we need-- an antigravity term called the cosmological constant.
  • 07:10: When it was later discovered that the universe is indeed expanding, Einstein retracted his constant.
  • 07:35: Einstein is right, even when he's wrong.

2016-03-16: Why is the Earth Round and the Milky Way Flat?

  • 02:15: Here it's fine to think about gravity Newtonianly as a force rather than as an Einsteinian warping of space time.

2016-03-02: What’s Wrong With the Big Bang Theory?

  • 01:06: ... by rewinding the laws of physics, and in particular running the math of Einstein's general theory of relativity ...

2016-02-24: Why the Big Bang Definitely Happened

  • 01:50: ... the context of Einstein's theory of general relativity, the only sensible interpretation for this ...

2016-02-11: LIGO's First Detection of Gravitational Waves!

  • 00:17: ... existence of these waves is the last major prediction of Einstein's theory of general relativity to be directly verified a century after the ...
  • 04:51: Well, everything else aside, it's a great vindication for Einstein's general relativity.
  • 05:09: So Einstein wins again.

2016-01-27: The Origin of Matter and Time

  • 00:00: [MUSIC PLAYING] Einstein's theory of special relativity has shown us mass and time are not the concrete things we imagine them to be.
  • 04:40: ... the invariance of the speed of light, the other fundamental principle of Einstein's special relativity at play here is the Galilean relativity of ...

2016-01-20: The Photon Clock Challenge

  • 00:35: And the resulting slowing of clock ticks due to motion is the time dilation of Einstein's theory of special relativity.

2016-01-13: When Time Breaks Down

  • 03:02: We're going to use a very close cousin to the photon box to explore time-- a thought experiment of Einstein's that we'll call the photon clock.
  • 04:28: This effect is the time dilation of Einstein's special relativity.
  • 05:20: But Einstein's equivalence principle tells us that a frame suspended in a gravitational field is indistinguishable from an accelerating frame.

2016-01-06: The True Nature of Matter and Mass

  • 00:02: NARRATOR: Einstein showed us that matter, mass, and the flow of time are intrinsically connected, but opened the question, are they even real?
  • 00:54: ... already covered Einstein's famous equation, E equals Mc squared, and showed that most of the mass ...
  • 06:23: ... we accept Einstein's description of space-time as described by general relativity, it's not ...

2015-12-09: How to Build a Black Hole

  • 00:56: Yet, to actually form a black hole, Einstein's descriptions of mass energy and space time are not enough.

2015-11-25: 100 Years of Relativity + Challenge Winners!

  • 00:24: ... this day in 1915, Albert Einstein first presented his complete theory of general relativity to the ...
  • 00:36: ... we cover a lot of material on this show, but Einstein's beautiful theory is an essential part of what inspires us here at "Space ...
  • 01:01: The elegance of this theory has inspired so many students of physics to follow in Einstein's path exploring the mysteries of the universe.

2015-11-11: Challenge: Can you save Earth from a Killer Asteroid?

  • 01:45: Never mind Einstein for now.

2015-10-28: Is The Alcubierre Warp Drive Possible?

  • 00:45: ... Alcubierre constructed a warp field in the mathematical language of Einstein's theory of general relativity, a real solution to the equations of GR ...
  • 02:03: ... the spacetime around and within a black hole is predicted by solving Einstein's field equations around a point of extreme positive energy ...
  • 03:05: ... you just make up a spacetime description and then essentially solve the Einstein equations backwards to figure out what arrangement of matter and energy ...
  • 05:46: ... that we're just making up solutions to the Einstein equations, we could even shrink down the warp bubble while expanding the ...

2015-10-22: Have Gravitational Waves Been Discovered?!?

  • 00:03: Gravitational waves are the last prediction of Einstein's Theory of General Relativity.
  • 00:17: What is it about Einstein?
  • 00:51: Einstein is amazing, because every one of these predictions from his beautiful work has been physically tested and verified.
  • 00:58: We love Einstein because he's been proven right so many times.
  • 02:25: ... speed limit comes from the fact that the speed of light is built into Einstein's field equation, which is necessary for it to be invariant to the Lorentz ...
  • 09:13: But if this is real, then Einstein's last great prediction will have been directly verified.

2015-10-15: 5 REAL Possibilities for Interstellar Travel

  • 11:58: Spooky action at a distance, as Einstein called it, on the surface does seem to mess with us.

2015-10-07: The Speed of Light is NOT About Light

  • 01:25: This is not Einstein's Relativity, but, instead, the brilliant precursor.
  • 05:14: And it was discovered even before Einstein's Relativity.
  • 05:17: ... it was Einstein who realized that the Lorentz transformation tells us how space and time ...
  • 05:26: Now, you can get to this transformation the way Lorentz and Einstein did by requiring a constant speed of light.
  • 09:19: ... Einstein's interpretation of the meaning of the Lorentz transformation gives us the ...
  • 09:36: ... space and time as described by the Lorentz transformation and we accept Einstein's interpretation of ...

2015-09-30: What Happens At The Edge Of The Universe?

  • 04:09: There's no doubt that Einstein was right in setting that limit for objects moving through space.
  • 05:26: If spacetime really is perfectly flat, then, with the most simplistic application of Einstein's equations, we get that the universe is infinite.
  • 06:59: We also have to keep in mind that these geometries assume that we can just extrapolate Einstein's equations in the most simplistic way.
  • 07:36: ... Squishina and others ask whether it's contradictory or circular to use Einstein's theory of general relativity to prove ...

2015-09-23: Does Dark Matter BREAK Physics?

  • 03:10: Either particle physics is wrong, or at least horribly incomplete, in that we're missing 80% to 90% of the mass in the universe, or Einstein is wrong.
  • 04:21: Any replacement theory has to reproduce all, and I mean all, of the verified predictions of Einstein's theory and be able to explain dark matter.
  • 05:33: Once again, Einstein prevails.

2015-08-27: Watch THIS! (New Host + Challenge Winners)

  • 00:09: There was a Newtonian and an Einsteinian version of the challenge.
  • 02:32: For the Einsteinian challenge, we had fewer than five people submit correct responses.
  • 02:43: Now explaining the answer to the Einsteinian challenge is a bit more involved because we don't know the geometry from the outset.
  • 03:50: What's the answer to the Einsteinian version of the two-particle challenge question?

2015-08-19: Do Events Inside Black Holes Happen?

  • 00:37: ... treat gravity Einsteinially rather than Newtonianially from the outset, it will help a lot if I can ...
  • 10:05: ... Einstein equations also allow for an empty universe that has an eternal black ...

2015-08-12: Challenge: Which Particle Wins This Race?

  • 04:09: Finally, I want to discuss the Einsteinian version of this question.
  • 04:31: ... have to solve the Einstein equations in the presence of a spherically symmetric perfect fluid whose ...
  • 04:58: You can submit your answers to that challenge by email with the subject line "Two-particle Einsteinian gravity challenge".
  • 05:09: You can only enter one challenge, though, Newton or Einstein.
  • 05:16: ... you can enter the Einsteinian challenge at all, that means you can solve the Newtonian challenge in ...
  • 05:29: But you also have more time, and both the Newtonian and Einsteinian versions of the question are pretty fun exercises.

2015-08-05: What Physics Teachers Get Wrong About Tides!

  • 02:04: It's not that Einstein can't explain tides.
  • 13:33: But Einstein says, hold on.
  • 14:04: Einstein says, you don't really have a choice.
  • 14:27: In other words, Einstein says the standard of non-acceleration can only be defined locally in small spacetime patches.

2015-07-29: General Relativity & Curved Spacetime Explained!

  • 00:14: [THEME MUSIC] Newton's and Einstein's dispute over gravity comes down to competing notions of what constitutes an inertial frame of reference.
  • 00:36: But Einstein says, nuh-uh, it's the apple's frame that behaves like a frame in deep space.
  • 00:55: Well, between our gravity illusion episode and your comments, we've seem that Einstein's position seems internally inconsistent.
  • 01:11: Today we're finally going to show how curved spacetime makes Einstein's model of the world just as self consistent as Newton's.
  • 01:18: ... one is to express both Newton's and Einstein's viewpoints in geometric spacetime terms, since that's the only way to ...
  • 02:19: Now for Einstein's position.
  • 03:18: OK, Einstein's position is that Newton is making the same mistake as the ant.
  • 04:32: ... according to Einstein, it happens because the apples are on initially parallel geodesics that, ...
  • 05:04: OK, so Einstein's gravity-free curved space time sounds like it's self consistent.
  • 07:32: Its curvature in geodesics are determined by how much energy is present at those events via set of rules called, no surprise, the Einstein equations.
  • 07:40: So for example, say you stick the energy distribution of the sun into the Einstein equations and turn a crank.

2015-07-22: SPECIAL ANNOUNCEMENT + Flat Spacetime Geometry Comments

  • 04:48: ... this is part of what prompted Einstein to want to develop a more general way of talking about the world that ...
  • 05:41: ... we dive into Part 3-- curved space time, and, finally, an explanation of Einstein's self-consistent view of what gravity ...

2015-07-02: Can a Circle Be a Straight Line?

  • 00:00: [MUSIC PLAYING] Einstein said that gravity is not a force.
  • 00:57: In that episode we noted objections to Einstein's viewpoint, many of which you echoed in the comments.

2015-06-17: How to Signal Aliens

  • 06:55: ... in the last episode, I was just trying to give the gist of Einstein's early thinking about gravity, which evolved and to give you a general ...

2015-06-03: Is Gravity An Illusion?

  • 00:26: But according to Einstein, there's no such thing as a gravitational force.
  • 00:42: ... today I'm going to clarify what exactly this point of view means, why Einstein came to adopt it, and how it planted the seeds for what would eventually ...
  • 05:39: ... Einstein asked, hold on, what if the so-called "real" downward gravity from Earth ...
  • 06:07: Well, not so fast, says Einstein.
  • 06:53: Einstein says, look buddy, I'm just following your rules.
  • 07:21: Einstein called it the equivalence principle, and if you buy it, then maybe the falling frames really are inertial.
  • 07:59: Now Newton says, nice try, Einstein, but you forgot something-- Earth is round.
  • 08:27: Second, by your criterion, Einstein, orbiting frames of reference-- like on the space station-- should also be considered inertial.
  • 08:44: So it looks like game over for Einstein, right?
  • 08:48: It turns out that there's a loophole that makes Einstein's viewpoint self-consistent.
  • 09:12: It took Einstein about seven years to realize that.
  • 09:57: For now, just reflect on Einstein's inspired thinking and how he got there, maybe next time you get in a car or a train.

2015-05-20: The Real Meaning of E=mc²

  • 00:16: ... most famous equation in all of physics, but in his original 1905 paper, Einstein actually wrote it down differently, as m equals E divided by c ...
  • 01:33: According to Einstein, the watch that's running has a greater mass.
  • 02:28: That's why, according to Einstein, most of us have always incorrectly believed that mass is an indicator of the amount of matter in an object.
  • 08:15: First, Einstein's original paper on this topic is only three pages long and not that hard to read.

2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi?

  • 00:53: Whether you want to think of gravity in the Newtonian or the Einsteinian sense, the problem persists.

2015-04-22: Are Space and Time An Illusion?

  • 00:41: This is challenging for everyone, even Einstein.
  • 04:13: ... shortly after relativity first came out, a former math professor of Einstein's named Hermann Minkowski noticed that the spacetime interval resembles a ...
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