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

  • 00:03: ... of both space and time okay we start in this description with newtonian physics in which they're the dimensions that form the stage on which ...

2022-01-12: How To Simulate The Universe With DFT

  • 06:03: In other words, Newtonian mechanics.
  • 07:15: In the Newtonian case, particles only interact locally, and that means the Newtonian equations of motion are what we call separable.
  • 07:46: ... fact in Newtonian mechanics we can not only write down the equations of motion for each ...
  • 08:02: But if we want to keep the quantum behaviour of quantum mechanics we can’t throw away most of configuration space like we do in Newtonian mechanics.
  • 10:54: Because they aren’t interacting, the equations of motion for these electrons are separable, just like in Newtonian mechanics.

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

  • 14:10: ... ways to break general relativity. There was the one on modified newtonian dynamics as an explanation for dark matter, and the one on fuzzballs - ...

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

  • 02:52: ... Einstein found that Newtonian gravity  breaks down when the gravitational field gets too strong - ...
  • 03:08: But Einsteinian gravity looks exactly like Newtonian gravity when gravitational fields get weak.
  • 03:18: What if Newtonian gravity breaks down  both for very strong AND very weak fields?
  • 03:25: This is the idea behind Modified Newtonian Dynamics, or MOND, proposed by Israeli physicist Mordehai Milgrom in 1982.
  • 06:10: ... Instead it does what it was designed to do - it reproduces good ol’ Newtonian ...
  • 09:53: ... acted like Newtonian mechanics on solar system scales, like MOND on galactic scales, and like ...

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

  • 05:52: ... motivations in developing general relativity was the fact that Newtonian mechanics failed to correctly predict the orbit of Mercury. If you ...
  • 18:52: ... Constructor theory might be another alchemy, or it might be another Newtonian mechanics. Shall we find ...

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

  • 01:43: ... can derive all of thermodynamics and Newtonian mechanics and electromagnetism and so on from two master theories: ...

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

  • 01:17: ... picture, and that light behaves like any other particle in response to Newtonian ...

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

  • 00:34: ... even gravity worked as Newton had told us.   In 1915, Newtonian gravity was superseded by Einstein’s general theory of ...

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

  • 05:33: The representation of the block universe that I showed you is very Newtonian.

2020-09-08: The Truth About Beauty in Physics

  • 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.

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

  • 00:00: ... like popper said then in that case the theory that newton of newtonian physics is really just as bad as the theory that earth is flat they're ...

2020-06-08: Can Viruses Travel Between Planets?

  • 14:22: ... theory is modified newtonian dynamics - MONDS - in which gravity doesn’t drop off as quickly as the ...

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

  • 11:20: ... contradicts Galilean relativity, and so revealed a crack in the sacred Newtonian mechanics. This directly inspired Hendrik Lorentz to derive his Lorentz ...

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

  • 12:40: The solutions only exist in special cases for Newtonian gravity.

2019-10-15: Loop Quantum Gravity Explained

  • 15:35: ... counters the gravitatinally attraction - if you'll forgive my crude Newtonian ...

2019-09-23: Is Pluto a Planet?

  • 03:19: That same motion almost perfectly reflected the clockwork predictions of Newtonian mechanics.

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

  • 00:03: ... of gravitational theory itself the first such proposal was Mons modified Newtonian dynamics proposed by Mordecai Milgram in the early 80s the idea is the ...

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

  • 03:19: OK, so how do negative masses work in Newtonian mechanics?
  • 03:28: In fact, in Newtonian gravity, any like masses – both positive or both negative - should produce a mutually attractive force.
  • 08:18: So far this seems to echo the Newtonian prediction.
  • 08:42: But this should crudely translate to the case of two equal-sized objects, although not in the simple, linear style of Newtonian mechanics.

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

  • 04:26: But for now let’s follow the paper’s argument, which is based on Newtonian physics.
  • 04:31: In Newtonian gravity, you multiply the two masses together along with some other stuff to get the strength of their mutual gravitational attraction.
  • 04:58: Dr. Farnes takes the Newtonian argument a step further.
  • 05:43: According to this Newtonian interpretation.

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

  • 02:49: But the Schrodinger equation treats space and time as fundamentally separate in the old-fashioned Newtonian way.

2018-07-18: The Misunderstood Nature of Entropy

  • 10:22: ... the laws of motion, whether Newtonian or quantum mechanical, don't care about the direction of time, and yet, ...

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

  • 05:00: The law of conservation of energy is fundamental in Newtonian mechanics, in which space and time are unvarying and eternal.

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

  • 08:40: ... the existence of gravitational waves, he had to master it precursor, Newtonian ...
  • 08:56: ... already done some serious university-level physics, then mastering Newtonian gravity is also your next step toward understanding Einstein's view of ...
  • 09:10: ... from the basics of classical mechanics through the intricacies of Newtonian ...

2018-02-14: What is Energy?

  • 01:53: Newtonian mechanics had only recently revolutionized physics.
  • 03:04: But that's just Newtonian mechanics.
  • 07:08: Newtonian mechanics is great at describing the motion of simple systems of a few rigid objects.
  • 07:56: ... its conservation has led to new types of mechanics that have supplanted Newtonian mechanics, for example Lagrange mechanics, which, in its simplest form, ...
  • 08:12: It produces the same equations of motion as Newtonian mechanics but without having to keep track of those innumerable fiddly force vectors.

2017-01-19: The Phantom Singularity

  • 07:00: This gives us the same infinite gravitational pull as the Newtonian singularity.
  • 07:05: And just as with the Newtonian case, this gravitational singularity can only exist if infinite densities are possible.

2016-12-21: Have They Seen Us?

  • 16:17: ... the escape velocity at the surface of the Earth because we're used to Newtonian approximations ...
  • 16:49: ... happen to get exactly the right size for the event horizon if you use Newtonian gravity to calculate the distance at which the escape velocity reaches ...

2016-05-25: Is an Ice Age Coming?

  • 13:58: ... that the law of conservation of energy, as we learned when we studied Newtonian mechanics, is a feature of flat ...
  • 14:12: ... gravity from a Newtonian perspective requires the invention of a new quantity-- gravitational ...

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

  • 11:35: This law is a property of a Newtonian universe, in which space and time are fixed static dimensions.

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

  • 02:16: ... let's develop intuition a bit by thinking about gravity from a Newtonian perspective-- as a force, rather than as an Einsteinian spacetime ...
  • 03:40: ... this Newtonian analogy-- and, remember, ignoring dark energy-- the universe also has an ...
  • 09:29: And to understand how does so will take us far beyond the capacity for Newtonian analogy.

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.

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

  • 01:32: But for now we have some math to do and it's all going to be Newtonian.
  • 02:13: ... some Newtonian mechanics to see how much mass is needed to accelerate Apophis to get ...

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

  • 04:05: The original modified Newtonian dynamics hypothesis, and it's a general relativity extensions, tries to give us this basic relationship for gravity.

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

  • 00:09: There was a Newtonian and an Einsteinian version of the challenge.
  • 00:13: Let's start with the answer to the Newtonian version.
  • 00:15: ... key to the Newtonian challenge was getting an expression for the gravitational force on the ...
  • 01:26: This is kind of a coincidence of the specific situation of a uniformly dense planet and Newtonian mechanics.
  • 05:05: But remember, the Newtonian solution is also there.

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 rely on technical terms ...
  • 07:03: ... Newtonian gravity, a projectile on the surface of a planet or a star needs a ...

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

  • 00:17: For the purposes of this challenge, I want you to treat gravity and all physics Newtonianly.
  • 00:59: ... Newtonian gravity, you can work out an expression for the orbital speed of this ...
  • 03:35: Use the subject line "Two-particle Newtonian gravity challenge".
  • 05:16: ... can enter the Einsteinian challenge at all, that means you can solve the Newtonian challenge in about 60 seconds, which isn't much of a ...
  • 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!

  • 02:01: Assumption one-- we're going to use Newtonian gravity.
  • 03:09: And in Newtonian physics, it's fake.
  • 13:18: In the Newtonian sense, acceleration would mean put a frame of reference at Earth's center.

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

  • 02:08: ... Newtonian gravity would just be an additional force we introduced, like any other ...
  • 08:22: So we often think in Newtonian gravitational terms, because it's easier, and because the resulting errors are usually small.

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

  • 02:58: Remember, in Newtonian physics, there's no unambiguous answer to that question, because you can only talk about motion relative to other things.
  • 03:22: Those are the guys that, it turns out, corresponds to inertial observers in Newtonian physics.

2015-07-15: Can You Trust Your Eyes in Spacetime?

  • 01:30: Pretend the world has no gravity, Newtonian or otherwise.
  • 06:38: In Newtonian mechanics, we distinguish inertial and noninertial observers dynamically by using the floating ball test.

2015-07-08: Curvature Demonstrated + Comments

  • 06:34: ... the curves and vectors in that space mean, and how it helps explain away Newtonian ...

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

  • 01:21: ... how it lets you account for the motion we observe even if there's no Newtonian force of ...

2015-06-17: How to Signal Aliens

  • 07:26: ... pointed out that you can distinguish ordinary celebration from real Newtonian gravity, because real gravity will vary in strengths slightly at both ...
  • 09:42: All directions are equivalent in the absence of some kind of real gravity in the Newtonian sense picking out some direction.

2015-06-03: Is Gravity An Illusion?

  • 01:49: Now in Newtonian physics, inertial frames are special because Newton's second law, F equals ma, is only valid in inertial frames.
  • 02:41: Inertial frame and non-accelerating frame are synonyms in Newtonian physics.
  • 03:26: There's something else familiar that makes people, books, and elephants accelerate in lockstep-- the Newtonian force of gravity.
  • 05:31: Now in Newtonian physics, this is just an accounting trick that has no broader significance.

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.
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