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2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table?

  • 17:30: Nick Bostrum’s self-sampling assumption tries to clear this up.

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

  • 06:17: The authors’ best guess is between 4 and 8, admittedly with some major assumptions.
  • 13:55: At least, given the assumptions of this model.
  • 14:45: Remember, this is a model, and it’s conclusions are only as good as the assumptions behind the model.

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

  • 06:01: ... theory is right, and forget   about the fact that some of the assumptions of AdS/CFT definitely do NOT apply to our ...
  • 06:54: ... of the AdS/CFT solution, but they don’t depend on its significant assumptions of ...

2022-05-04: Space DOES NOT Expand Everywhere

  • 03:27: ... FLRW metric makes some pretty big assumptions - that the matter in the universe is perfectly evenly spread out - ...
  • 04:54: ... latitude and longitude. Those lines are smooth because of our founding assumptions of homogeneity and isotropy. But if we zoom in we can see that the shape ...

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

  • 09:06: ... assumption of homogeneity and zero pressure was the same that Alexander Friedmann ...

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

  • 02:41: ... today I want to dig deeper and see what assumptions are behind this interpretation, and also ask what it would mean if those ...

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

  • 15:07: The assumption in this calculation is that the black hole came from interstellar space and fell into the solar system.

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

  • 05:06: But that assumption may be wrong.

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

  • 17:54: ... also puts it well: If we assume the universe operates under certain assumptions (infinite/finite, discrete/continuous spacetime, invariance, quantum ...

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

  • 04:10: But these are still hacks - approximations that involve different assumptions, or only work in certain ideal circumstances.
  • 04:19: One big assumption is that the space near the event horizon isn’t TOO strongly curved compared to the smallest quantum scale.
  • 04:26: ... Hawking made that assumption, it enabled him to mathematically connect the high-gravity region near ...

2021-03-23: Zeno's Paradox & The Quantum Zeno Effect

  • 14:22: ... either the CMB or supernova measurements, but also by finding one of the assumptions in the CMB calculation is wrong - which would force us to change our ...

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

  • 01:04: Michell and Cavendish used the same utterly wrong assumptions to do their calculations.
  • 01:26: But the weird thing is that despite these incorrect assumptions, the effects that these guys predicted have proved very real.
  • 04:47: ... and have it fall back, as calculated by Michell from totally wrong assumptions. ...
  • 09:17: ... just need two completely crazy assumptions - first that light acts like a very classical, 17th-century style plane ...

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

  • 00:17: ... theory started with the simple assumption that the speed of light was the fastest speed possible, and that all ...

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

  • 04:35: ... Penrose showed that according to Einstein’s theory plus a couple of assumptions,   black holes must contain singularities. And this is true regardless ...

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

  • 01:54: Newton’s picture of the universe included one other assumption that we know for sure is wrong.

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

  • 08:04: But then a simple modification to the founding assumptions caused this mess to collapse into a supremely elegant form.
  • 08:28: Oh, by the way, the modified assumption that led to Dirac’s miraculous algebraic convergence?

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

  • 08:24: ... get the total quantity of each ion or of the element, with certain assumptions she could get the relative amounts of the elements compared to each ...

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

  • 00:00: ... when you do that and you try to keep quantum mechanics consistent the assumptions you made about quantum mechanics pops out of the equations out of ...

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

  • 15:10: The quality of the predictions of any model depend on the assumptions that go into it.
  • 15:16: And in the case of the black holes, several unreasonable assumptions allow us to trace geodesics into alternate universes.
  • 15:24: ... universe through the non-rotating Schwarzschild black hole requires the assumption that the black hole has been there ...
  • 15:33: ... string of universes through the rotating Kerr black hole requires the assumption that the impossibly unstable inner structure of the Kerr spacetime ...

2020-03-03: Does Quantum Immortality Save Schrödinger's Cat?

  • 09:08: Depending on some assumptions like the average lifespan you get that something like 17-18 trillion people will have lived by the year 3000.

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

  • 04:25: That is, IF our assumptions are right.
  • 10:21: We covered most of the important assumptions in this crazy hypothesis - except the main one.

2020-01-27: Hacking the Nature of Reality

  • 07:12: ... and momentum, the behavior of quantum properties like spin, and the assumption of a family of particles that can be involved in the ...

2020-01-13: How To Capture Black Holes

  • 11:18: ... — assuming accretion disk mergers are really happening, and that all the assumptions of the model hold ...

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

  • 16:08: ... 3: Assume self-sampling assumption makes sense and internet access is bell curved over over the duration of ...

2019-12-09: The Doomsday Argument

  • 02:49: ... the assumption that lower cosmological constants were less likely than higher ones, ...
  • 03:31: ... that most astronomers across the multiverse would observe, with a few assumptions like that the number of astronomers in a universe is proportional to the ...
  • 04:15: ... rather than environments is essentially using the Self-Sampling Assumption, defined by philosopher Nick Bostrom as follows: “All other things equal, ...
  • 06:46: Let’s apply the self-sampling assumption and imagine that you could have been any one of the past and future humans of our species.
  • 08:17: ... principle is interpreted, in particular through the self-sampling assumption and the definition of your reference ...
  • 08:54: In the doomsday argument, the assumption is that our “reference class” is all past and future humans.

2019-12-02: Is The Universe Finite?

  • 09:12: It’s the statistical confidence in the model fit given the assumptions that went into the model.
  • 09:19: ... other words, IF all of those assumptions are correct then there’s less than 1% chance that a flat universe would ...
  • 09:36: Two is that the assumptions that went into the model are wrong.

2019-11-18: Can You Observe a Typical Universe?

  • 09:08: ... the assumption that our universe resulted from a simple random fluctuation in an ...
  • 10:08: ... it he defines, although doesn’t invent, the self-sampling assumption, which states that “All other things equal, an observer should reason as ...
  • 10:41: The anthropic principle and the self-sampling assumption encourage Bayesian thinking.
  • 11:25: ... we covered, to the doomsday argument - the idea that the self-sampling assumption predicts that the end of the world is nigh - which we’ll cover soon - ...
  • 16:43: ... self-sampling assumption says we should assume we're a typical observer - so maybe the most ...

2019-10-15: Loop Quantum Gravity Explained

  • 11:13: And without adding big assumptions – like the existence of strings or extra dimensions or supersymmetry.

2019-10-07: Black Hole Harmonics

  • 05:27: Matthew Giesler, Max Isi, Mark Scheel and Saul Teukolsky of CalTech and MIT went against this these prior assumptions in their recent paper.

2019-04-10: The Holographic Universe Explained

  • 10:23: ... certain assumptions he found that the resulting braney structure looked just like a ...

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

  • 10:10: With this sort of highly speculative science, you really have to dig down and look at the assumptions in ALL of the theory.
  • 10:54: Well it turns out that there were hidden assumptions even in that effort.
  • 11:22: Either way, the structure of geodesics have inbuilt the assumption of the equivalence of gravitational and inertial mass.

2019-01-24: The Crisis in Cosmology

  • 00:21: ...some of the most basic assumptions about the universe.
  • 03:42: But this calculation involves assumptions and uncertainties.

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

  • 06:59: To make the same negative mass stuff also emulate dark energy requires an extra gigantic assumption.

2018-12-12: Quantum Physics in a Mirror Universe

  • 00:02: ... at least somewhat targeted to star systems or even planets depending on assumptions evolving a technological civilization to the point that they can ...

2018-10-18: What are the Strings in String Theory?

  • 14:50: This is one of the assumptions we made in the calculation.

2018-10-10: Computing a Universe Simulation

  • 10:43: ... so wildly different results depending on your assumptions-- by the way, getting your results of the simulation will take forever, ...

2018-09-12: How Much Information is in the Universe?

  • 10:26: You're going to need to make a bunch of assumptions, and there isn't a single perfect answer.

2018-07-25: Reversing Entropy with Maxwell's Demon

  • 11:43: Iago Silva criticizes our assumption of the ergodic hypothesis.
  • 11:49: ... the non-physicists out there, the ergodic hypothesis is basically the assumption that all microstates are equally probable over long periods of ...
  • 12:01: Starting with this assumption gets you to the Boltzmann equation, and it's a nice, relatively simple way to understand entropy.

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

  • 06:49: And this unitarity is a foundational assumption in all formulations of quantum mechanics and quantum field theories.

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

  • 06:56: It's a founding assumption behind these derivations, and it's also the founding assumption behind Noether's theorem.
  • 07:02: However, as a founding assumption, that is as close to as fundamental as we can get.

2018-02-28: The Trebuchet Challenge

  • 05:19: I should add that we're making a few assumptions here.
  • 05:35: These assumptions aren't entirely reasonable.

2017-08-24: First Detection of Life

  • 00:58: ... life on a world using only data taken from space, and with as few prior assumptions as ...

2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson

  • 03:23: That under certain assumptions, virtual minds should vastly outnumber real minds in our universe.
  • 05:52: But whatever, let's go with Bostrom's assumption.

2017-04-26: Are You a Boltzmann Brain?

  • 09:25: ... caution in arguing probabilities before really understanding the prior assumptions. ...

2017-01-11: The EM Drive: Fact or Fantasy?

  • 08:29: ... none of this is relevant unless the founding assumption is right, that the vacuum is something very different than described by ...

2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers

  • 05:11: ... in the pessimistic assumption that we are the only technological civilization in the neighborhood, and ...
  • 06:47: ... nearest Type II, Dyson Swarm-capable civilization should be, under the assumption that the weird dimming seen in Tabby's Star is due to a Dyson Swarm and ...

2016-10-05: Are We Alone? Galactic Civilization Challenge

  • 03:03: ... in the Milky Way, they asked the following-- In the deeply pessimistic assumption that humanity is the only technological civilization in the entire known ...

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

  • 01:04: ... existing when we're not looking at it is a pretty fundamental implied assumption behind all of classical ...
  • 02:40: ... proposed a quantum scenario that showed that in order to abandon the assumption of realism, you also had to abandon a concept almost as sacred-- ...

2016-07-06: Juno to Reveal Jupiter's Violent Past

  • 11:41: ... I said that the assumption of infinite divisibility of space was a problem with the scenario in ...

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

  • 04:33: We need to throw out that assumption because it is giving us the wrong answer.
  • 04:37: That's a science thing, questioning your assumptions.

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

  • 02:38: In fact, we now know that even Newton's mechanics were using assumptions that implied an infinite speed of light, which is really bad.

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

  • 01:50: So right up front, I want to make some assumptions to simplify the analysis and to remove unimportant factors from the picture.
  • 02:01: Assumption one-- we're going to use Newtonian gravity.
  • 02:10: Assumption two-- let's ignore the Sun.
  • 02:18: Assumption three-- we're going to pretend the Earth is uniformly covered with one humongous ocean and no continents.
  • 02:24: And finally, assumption four-- we're going to pretend that we can switch Earth's gravity on and off whenever we want to.

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

  • 05:49: ... making any assumptions about how gravity effects light, that would be true even if it turned ...

2015-06-24: The Calendar, Australia & White Christmas

  • 06:27: And the operating assumption of SETI for several decades is that maybe aliens are broadcasting such a beacon into space.

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

  • 07:20: First of all, that assumption is unnecessary.

2015-02-18: Is It Irrational to Believe in Aliens?

  • 03:48: That a species would spread out isn't some crazy assumption on our part.
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