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

  • 18:14: ... I define my reference class as those who are able to formulate anthropic arguments then it’s less surprising that I live in a modern ...

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

  • 02:43: ... universe, including our expiry date, check out our video on the Doomsday argument. ...

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

  • 09:05: We’ve talked about this  anthropic argument in the past.

2022-09-21: Science of the James Webb Telescope Explained!

  • 16:13: nyrdybyrd points out that the info from this Higgs episode is an influential argument for a badass new particle collider.

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

  • 10:08: ... This could be a crazy coincidence, or perhaps there are anthropic arguments for this - for example we could only exist in such a ...

2022-06-22: Is Interstellar Travel Impossible?

  • 19:30: Hawking’s original argument talked about perturbing the positive and negative frequency modes of the quantum vacuum.

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

  • 11:08: ... holes to make them look like our universe from within, and Hawking’s argument that equates white holes with black holes, then there’s a roundabout way ...

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

  • 02:31: Now you can’t just erase mass, but let’s pretend that you can for the sake of argument.
  • 08:39: ... of sending information across an event horizon brings us to our last argument, and this one works whether we’re talking about the classical gravity of ...
  • 10:30: And this last argument also tells us how it can be that a black hole can possess electric charge.

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

  • 10:02: ... that we need to assume about the mechanistic theory in order to make the argument - in this case, just the way informational elements interact, say, by ...

2021-10-05: Why Magnetic Monopoles SHOULD Exist

  • 05:58: His argument goes something like this.
  • 06:30: ... construction is called the “Dirac string”, and Dirac’s argument is that if the string part of the Dirac string is fundamentally ...
  • 06:43: The second part of the argument is under what conditions that string is undetectable.
  • 07:42: ... integer multiples of that basic charge This is a very loose form of the argument - and you can get to it in different ...

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

  • 13:56: Karina makes a similar style of argument - saying that this crazy idea just makes it even more convincing that Schrodinger's equation is linear.

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

  • 06:27: ... But it’s exactly this illusion of logic that makes the Sherlock argument so misleading, and by far the most common cause of false declarations ...

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

  • 08:17: A flurry of papers came out after the 1990 result disputing the claim on various grounds, and the arguments have continued.

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

  • 04:43: But Schrodinger had his arguments too.
  • 12:06: ... a century after Bohr and Schrodinger started the argument, we may be on the verge of the next quantum leap - to learning whether ...
  • 04:43: But Schrodinger had his arguments too.

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

  • 08:11: ... this is one argument for the direction of the arrow of time. If we think of time as just a ...

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

  • 10:53: ... talk about the fourth argument against free will in my earlier list, that a purely mechanistic process ...

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

  • 03:18: ... Kerr solution was still highly symmetrical,   so the same old arguments held against  these things forming in ...
  • 13:38: ... it.   As for falsifiability - I’ll try to give Sean  Carroll’s argument for this one. Many Worlds can   be considered the “cleanest” ...
  • 03:18: ... Kerr solution was still highly symmetrical,   so the same old arguments held against  these things forming in ...
  • 10:36: ... showed that Penrose’s arguments  about black holes also applied to the   universe - that ...
  • 09:31: ... In his PhD thesis Hawking   showed that you could use the same arguments to investigate the behavior of geodesics traced   backwards ...

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

  • 00:00: ... and so on and so forth and i just think that's that's an unscientific argument and i think it's terribly embarrassing if uh scientists go go on and ...

2020-06-22: Building Black Holes in a Lab

  • 11:04: ... can analog black holes actually tell us about real black holes? Early arguments in the late ‘90s claimed that because Hawking radiation should appear ...

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

  • 07:35: ... was from our Doomsday Argument episode a couple of months back - sorry to be slow - I wanted to check ...
  • 07:51: ... to refresh your memory real quick, the argument goes like this: we are typical members of the human race, which means we ...
  • 09:18: ... place you in the first .6% of people who ever lived - and the Doomsday Argument argues that, therefore, there's less than a 1% chance that so many ...
  • 09:36: ... some people used much more sophisticated probability arguments including Bayesian analysis or thinking in “observer years” rather than ...
  • 10:13: And the smaller our population is, the longer humanity lasts - according to the Doomsday argument.
  • 10:18: This has nothing to do with sustainability - it’s just this weird statistical argument.
  • 10:23: ... we’d last for trillions of years … Hmmm, that does make the Doomsday Argument seem even more ...
  • 09:18: ... place you in the first .6% of people who ever lived - and the Doomsday Argument argues that, therefore, there's less than a 1% chance that so many people will ...
  • 07:35: ... was from our Doomsday Argument episode a couple of months back - sorry to be slow - I wanted to check my ...
  • 09:36: ... some people used much more sophisticated probability arguments including Bayesian analysis or thinking in “observer years” rather than ...

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

  • 08:34: I simplified this argument a bit, but elaborating doesn’t change the conclusion.

2020-01-13: How To Capture Black Holes

  • 02:50: ... argument goes like this: we know that the center of almost every galaxy contains ...

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

  • 07:56: ... Smolin has various arguments against this: for example, we don’t know that our physics can really be ...
  • 08:09: ... would also add that even if Vilenkin’s argument holds, there are no doubt different regions in the landscape of possible ...
  • 13:46: ... can check out at pbsspacetime.com Last week we talked about the doomsday argument - the unnerving idea that, statistically speaking, there are aren't ...
  • 14:07: There were a lot of counter arguments - perhaps good ones because apparently we're still here.
  • 14:30: ... we accept the reasoning of the doomsday argument, doesn't this just mean that everyone, for all of history, would come to ...
  • 14:52: But the doomsday argument isn't saying that every member of a species who employs this reasoning to predict their species doom is going to be right.
  • 15:20: ... randomly sample from all generations who thought about the doomsday argument then chances are they didn't come near the start of their ...
  • 15:34: Now, the real problem with the doomsday argument isn't that users of it in the distant past would be wrong.
  • 15:41: Rather, it's that it's not at all clear that it's reasonable to count ourselves as "randomly selected" from all of the users of the doomsday argument.
  • 17:27: Nick Bostrom has another nice example of misusing the doomsday argument.
  • 17:38: The serpent comes along and explains that according to the doomsday argument the chances of Eve getting pregnant are nearly zero.
  • 13:46: ... can check out at pbsspacetime.com Last week we talked about the doomsday argument - the unnerving idea that, statistically speaking, there are aren't likely ...
  • 14:30: ... we accept the reasoning of the doomsday argument, doesn't this just mean that everyone, for all of history, would come to the ...
  • 08:09: ... would also add that even if Vilenkin’s argument holds, there are no doubt different regions in the landscape of possible ...
  • 14:52: But the doomsday argument isn't saying that every member of a species who employs this reasoning to predict their species doom is going to be right.
  • 15:34: Now, the real problem with the doomsday argument isn't that users of it in the distant past would be wrong.
  • 07:56: ... Smolin has various arguments against this: for example, we don’t know that our physics can really be ...
  • 14:07: There were a lot of counter arguments - perhaps good ones because apparently we're still here.

2019-12-09: The Doomsday Argument

  • 00:13: But a simple statistical argument tells us that the doom of our species is much, much closer.
  • 04:58: Allow me to introduce you to the Doomsday Argument, also known as the Carter Catastrophe, after Brandon Carter who came up with it.
  • 07:51: This is the doomsday argument.
  • 08:17: ... are many proposed refutations of the doomsday argument - more than we can go into - but it’s worth covering some that get at ...
  • 08:54: In the doomsday argument, the assumption is that our “reference class” is all past and future humans.
  • 09:51: ... issue is that the doomsday argument is assigning some sort of reality to the two scenarios - doom-early and ...
  • 11:20: ... it can lead to dubious but worrying predictions like the doomsday argument, and it can lead to some pretty absurd ideas like the Boltzmann ...
  • 11:43: Assuming the doomsday argument are valid, what are the chances that humanity will last until the year 3000?
  • 12:16: ... is coming soon or late, here’s a positive spin on the whole doomsday argument: the chances of us being in the final generation of our civilization are ...
  • 08:17: ... are many proposed refutations of the doomsday argument - more than we can go into - but it’s worth covering some that get at how ...
  • 00:13: But a simple statistical argument tells us that the doom of our species is much, much closer.

2019-12-02: Is The Universe Finite?

  • 14:24: Well, nice way to invent the doomsday argument Vladimir... like 35 years after Brandon Carter first proposed it.

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

  • 11:25: ... it can make - from Boltzmann brains, which we covered, to the doomsday argument - the idea that the self-sampling assumption predicts that the end of ...
  • 14:36: Well, actually, fine tuning arguments for the fundamental constants for the most part take that into account.
  • 11:25: ... it can make - from Boltzmann brains, which we covered, to the doomsday argument - the idea that the self-sampling assumption predicts that the end of the ...
  • 14:36: Well, actually, fine tuning arguments for the fundamental constants for the most part take that into account.

2019-11-11: Does Life Need a Multiverse to Exist?

  • 03:47: We’re going to delve much more deeply into the implications and validity of that argument in an upcoming episode.

2019-10-21: Is Time Travel Impossible?

  • 11:53: One final argument that time travel is impossible is that we don’t see time travelers.

2019-09-30: How Many Universes Are There?

  • 08:58: ... argument goes like this: if the number of new universes increases by a factor of ...
  • 09:37: The real timescale is going to be much more fuzzy than this, but it also doesn’t really matter for this argument.
  • 11:13: Guth calls this argument the Youngness Paradox.
  • 14:56: Last time we visited that old argument - Is Pluto a planet?
  • 15:37: ... are two main arguments - firstly that the IAU definition is arbitrary and ambiguous, second ...
  • 14:56: Last time we visited that old argument - Is Pluto a planet?
  • 15:37: ... are two main arguments - firstly that the IAU definition is arbitrary and ambiguous, second ...

2019-09-23: Is Pluto a Planet?

  • 15:36: Now, the argument is compelling: why would we want to go and live back down in a gravity world right after getting out of this one?

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

  • 00:03: ... for a galaxy to be missing dark matter which is an ironically powerful argument in favor of the existence of dark matter if dark matter isn't a ...

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

  • 14:12: ... it would break our current understanding of physics" ...is hardly a good argument. Now, while I agree that this isn't a hard rule, it's a good guiding ...

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.
  • 04:58: Dr. Farnes takes the Newtonian argument a step further.

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

  • 00:02: ... on that Nobel Prize in 1957 Wu conducted an experiment based on a simple argument if parity is conserved then there should be no experiment you can do to ...

2018-12-06: Did Life on Earth Come from Space?

  • 00:37: ... rocks slams into a newly habitable world perhaps the most convincing argument against panspermia is that if the dormant seeds of life are so common ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 04:22: This is the argument.
  • 07:42: But until someone does a proper calculation to show that tumbling must change in an observable way, this is not a serious argument.

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

  • 14:57: All of these arguments of aliens probably don't do this or that are what we call a soft filter.
  • 15:11: These arguments on alien psychology are soft filters.
  • 14:57: All of these arguments of aliens probably don't do this or that are what we call a soft filter.
  • 15:11: These arguments on alien psychology are soft filters.

2018-10-25: Will We Ever Find Alien Life?

  • 00:48: Enrico Fermi was supposedly using this as an argument against the plausibility of interstellar travel.

2018-10-03: How to Detect Extra Dimensions

  • 14:21: ... give better answers and then got into an extended and quite high-level argument about the right approach to understanding ...

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

  • 06:41: So this same argument can be used to suggest a fragmentation of time.

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

  • 06:42: Physicists tried to figure out a flaw in the argument.

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

  • 11:11: Merissan has plans to use the loss of energy in cosmological redshift as a refutation of conservation of energy arguments.

2018-05-02: The Star at the End of Time

  • 00:14: [THEME MUSIC] For the sake of argument, let's say that humanity survives the several ends of world that await us.

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

  • 06:50: Gravitational radiation should have physical effects as shown by the sticky bead argument first presented by Richard Feynman.

2018-03-07: Should Space be Privatized?

  • 04:41: So here we get to the main argument for public versus private space programs.
  • 06:47: Well, there are arguments on both sides.

2018-02-28: The Trebuchet Challenge

  • 05:12: You should be able to use simple energy arguments to calculate for your enemy's destruction.

2017-09-13: Neutron Stars Collide in New LIGO Signal?

  • 13:14: At any rate, by simple energy arguments, it just doesn't work for any weapon we now possess.

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

  • 01:56: That's an argument for why that that's more likely than any other scenario.
  • 07:28: Bostrom claims the following, which he calls the simulation argument.
  • 09:45: We already talked about Sean Carroll's argument against concluding that we are Boltzmann brains.
  • 10:51: Another big issue is just the potential for spectacular overreach in using these Copernican and entropic arguments.
  • 13:52: ... made the argument that the Boltzmann brain thought experiment fails because it assumes ...
  • 10:51: Another big issue is just the potential for spectacular overreach in using these Copernican and entropic arguments.

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

  • 08:29: Sean Carroll has another nice argument against Boltzmann brains.
  • 08:47: To expand on that, we can also go back to parsimony and the Copernican argument.

2017-03-15: Time Crystals!

  • 03:23: ... and Masaki Oshikawa of the University of Tokyo showed from theoretical arguments that time translational symmetry can't be broken by a quantum system in ...

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

  • 06:25: ... potential sources of false positive signal, and either make reasonable arguments against them or propose tests to rule them ...

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

  • 06:38: In fact, most of the arguments for or against it are about this special thinking.

2016-10-12: Black Holes from the Dawn of Time

  • 06:07: These arguments let us rule out all but a very narrow set of mass ranges for primordial black holes as an explanation for dark matter.

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

  • 04:31: The argument between Bohr and Einstein felt a bit philosophical at the time.
  • 11:52: OK, so the same statistical arguments for Von Neumann probes tells us that if we expect one, then we expect lots.

2016-09-14: Self-Replicating Robots and Galactic Domination

  • 08:17: OK, so alien psychology-- the exclusivity argument, that civilizations will never do certain things, is fatally flawed.

2016-01-13: When Time Breaks Down

  • 04:57: ... the way, similar arguments will show us that a photon clock in an accelerating reference frame-- ...

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

  • 01:11: So for argument's sake, let's say humanity's future is at stake, and we just discovered Earth 2.0 in the Alpha Centauri system.

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

  • 07:40: And honestly, just from the symmetry and relativity arguments that we made, c could be infinity.

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

  • 03:20: But if you think you have an airtight argument that doesn't require algebra, you're welcome to submit it.

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

  • 05:31: It's a cool argument, originally presented over 50 years ago by physicist Alfred Schild, and it goes like this.

2015-05-13: 9 NASA Technologies Shaping YOUR Future

  • 08:55: That's an excellent argument.
  • 09:06: Talia Enright pointed out that all these arguments could apply to a #OccupyVenus Cloud City mission.

2015-05-06: Should the First Mars Mission Be All Women?

  • 00:42: Today, I'm going to review some of the data underlying the various arguments.
  • 00:47: Let's start with the physiological arguments for all-female missions beyond Earth's moon.
  • 03:45: There's still another argument for preferring women to men on longer space missions-- namely that it costs less to send them to other planets.
  • 04:10: Now, this argument has been made many times over the years, including by some NASA employees.
  • 00:42: Today, I'm going to review some of the data underlying the various arguments.
  • 00:47: Let's start with the physiological arguments for all-female missions beyond Earth's moon.

2015-04-01: Is the Moon in Majora’s Mask a Black Hole?

  • 06:26: So there's my argument.

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

  • 01:54: There are sensible arguments both for and against the existence of aliens.
  • 02:01: None of those arguments is decisive.
  • 02:07: Let's start with a pro aliens argument, that intelligent life should exist.
  • 02:11: The argument says, look, 200 billion inhabitable planets, that's a huge number.
  • 03:25: Well, as it turns out, there's a way to turn this argument entirely on its head.
  • 03:29: One prominent no aliens argument begins by pointing out that our galaxy is not just very big, but also very old, about 10 billion years old.
  • 04:48: This argument was put forth by the physicist Enrico Fermi, among others.
  • 05:56: It's an argument that also has many proponents.
  • 06:32: ... knowing that it's possible to reconcile Sagan's billions and billions argument with the fact that Chewbacca wasn't at your office holiday ...
  • 01:54: There are sensible arguments both for and against the existence of aliens.
  • 02:01: None of those arguments is decisive.
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