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

  • 20:10: ... you know that’s another solution to the Fermi paradox - that the first civilization became cosmic horrors, obliterating ...
  • 20:32: Of course it’s exactly this thinking that gets you the dark forest solution to the Fermi Paradox.

2022-08-03: What Happens Inside a Proton?

  • 16:44: ... Dunmore proposes a non-quantum  version of the EPR paradox experiment:   Take a pair of gloves, put them in separate ...

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

  • 02:03: Along with Boris Podolsky and Nathen Rosen, he proposed the EPR paradox which was meant to deal a swift death-blow to this observer-centric nonsense.
  • 02:13: We’ve talked about the EPR paradox before, but it’s really worth a second look - especially given the stakes.
  • 03:36: Standard quantum mechanics says that this is possible, but it leads to the seemingly absurd result of the EPR paradox.
  • 05:24: The EPR paradox was meant to show that this sort of undefinedness couldn’t be the underlying reality because it violated the cosmic speed limit.
  • 06:25: It wasn't until 1960, nearly 30 years after the EPR paradox paper was published, that physicist John Bell gave us a concrete test for all of this.
  • 10:42: This way out of the EPR paradox is called superdeterminism.
  • 11:00: ... sort of uncanny convergence in that evolution needed to solve the EPR paradox; that’s what the super part is ...
  • 11:26: Others, like Sabine Hosenfelder, argue that superdeterminism is actually the cleanest solution to the EPR paradox.

2022-06-30: Could We Decode Alien Physics?

  • 15:41: ... or less is a strong factor  to consider when pondering the Fermi paradox.   We did an episode on this once upon a time.    Knurlgnar24 ...

2022-06-22: Is Interstellar Travel Impossible?

  • 00:18: Ever since Enrico Fermi asked his famous question “Where is everybody?” We’ve pondered the mystery of the Fermi Paradox.
  • 01:07: ... it because, frankly, I don’t want it to be the real answer to the Fermi paradox It’s the idea that we don’t see aliens because interstellar travel is ...
  • 04:20: And if the answer is no, have we solved the Fermi paradox in the least interesting way possible?
  • 13:58: And it's certainly not a clear explanation of the Fermi paradox.
  • 15:16: ... then we covered a new idea that might solve the black hole information paradox, involving a pretty crazily abstract idea including imaginary replica ...
  • 18:59: ... the no-hair theorem will be violated in order to solve the information paradox, but learning exactly how it’s violated would be ...
  • 19:50: ... looking at a wormhole say "Can this solve the black hole information paradox?" While Normal people looking at a wormhole are like "WOOHOO a wormhole, ...
  • 20:04: ... are more like “Hmm. . can this solve the information paradox and if so can can I figure out how to fly through wormholes?” Really, ...

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

  • 00:00: ... It turns out that in order to make  sense of their paradoxical nature,   we need to consider that each real black hole has ...
  • 00:26: ... provide a way forward. I’m talking about the black hole information paradox.   Efforts to resolve it have led to stunning  realizations about the ...
  • 01:40: ... remind ourselves what the black home   information paradox is all about. Feel free to  have a look at our original video on ...
  • 02:24: ... the most powerful way  to think about this paradox   is in terms of entropy. Think of  entropy as the amount of ...
  • 04:44: ... Efforts to resolve the black hole information   paradox have largely focused on ways to encode Hawking radiation with that ...
  • 05:20: ... hole. Any theory trying   to solve the black hole information paradox  has to exactly reproduce the Page ...
  • 06:01: ... mentioned that the information paradox  inspired the holographic principle. The most   advanced form ...
  • 12:09: ... virtual,  wormholey topologies solve the information   paradox? Well, it sort of looks like they might of. Using the gravitational path ...
  • 13:07: ... has the paradox really been solved? Well the community is divided. Some of the ...

2022-05-25: The Evolution of the Modern Milky Way Galaxy

  • 14:38: ... on the galactic habitable zone and its implications for the fermi paradox, and the one   where we showed why space is not expanding ...
  • 15:22: ... number for possible origins of life  to help explain the Fermi paradox. We want to find   out if even the most conservative estimate ...
  • 15:56: Some of you pointed out other  possible explanations for the   Fermi paradox and the specialness of Earth.

2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life?

  • 01:07: ... any other signs of technological life? This is the   Fermi Paradox, which of course we’ve talked about  before. But one possible ...
  • 12:04: ... for life in the Milky Way,   so we haven’t solved the Fermi Paradox. Quite  the opposite - we’ve made it worse. This team   ...
  • 13:03: ... So it sounds like we haven’t made progress  solving the Fermi Paradox. But actually we have.   There is a roadblock in the chain ...

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

  • 01:59: ... to share a single, consistent reality? Solutions to this seeming paradox spanned the spectrum. For example, the Hungarian physicists John von ...

2022-02-16: Is The Wave Function The Building Block of Reality?

  • 18:15: ... episode on that one. Check out our episode on the black hole information paradox for the full ...
  • 18:37: ... information that went in is gone. And this is the black hole information paradox that I mentioned. And I'll refer you to that episode for more answers. ...

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

  • 00:02: ... galaxy is full of life if um if life is common then per the fermi paradox we should have been visited many times and it should be very apparent ...

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

  • 00:02: Black holes are a paradox.
  • 00:04: They are paradoxical because they simultaneously must exist but can’t, and so they break physics as we know it.
  • 01:08: There’s our first paradox.
  • 01:10: And at the event horizon another paradox arises.
  • 03:40: This threat of erasure of quantum information in a hairless black hole is the black hole information paradox.
  • 03:48: So yeah, black holes seem to be paradoxes.
  • 03:56: Actual paradoxes.
  • 03:57: When we see an apparent paradox in physics, it’s really a clue pointing to a gap in our understanding.
  • 04:04: Solving the paradox can lead us to new knowledge.
  • 04:07: While we’ve covered these black hole paradoxes before, and have even hinted at possible solutions - we’ve never actually solved them.
  • 04:17: Ultimately, the black hole paradoxes stem from the disagreement between quantum mechanics and general relativity.
  • 05:28: Black hole paradoxes may be solved by string theory.
  • 07:31: But in order to solve the information paradox, we still have to get that information out of the black hole as it evaporates.
  • 13:00: ... hole could be and provided a satisfying potential resolution to several paradoxes. ...

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

  • 00:02: Paradoxically, the most promising prospects for moving matter around faster than light may be to put a metaphorical brick wall in its way.
  • 00:10: ... superluminal motion may be possible, while still managing to avoid the paradox of superluminal ...
  • 05:27: ... light, you can send signals into the past, and create a whole bunch of paradoxes. ...
  • 09:51: ... that was influenced by your message to them, which could then cause a paradox ...

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

  • 14:07: ... words, if the non-linearity of the schrodinger equation allows these paradox-generating phenomena, then we can take that as evidence against that ...

2021-06-09: Are We Running Out of Space Above Earth?

  • 16:05: ... tiny black holes everywhere perfectly explains one of the most vexing paradoxes in the field of domestic mechanics - as in it explains what happened to ...

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

  • 09:02: ... that was introduced with Hawking radiation - the black hole information paradox. ...

2021-04-21: The NEW Warp Drive Possibilities

  • 06:16: That leads to paradoxes - to contradictions and inconsistencies.
  • 16:22: ... the way, the name comes from the Zeno paradox, which argues that a moving arrow isn’t moving because it’s stationary at ...
  • 16:32: Raven Lord always thought that the idea of "instantaneous velocity" that solves this paradox is just a theoretical artifact of calculus.

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

  • 00:17: But Zeno, Greek philosopher famous for his metaphysical trolling, devised a paradox whose conclusion is just this.
  • 00:45: Nowadays, most physicists and mathematicians don’t really see Zeno’s arrow as paradoxical.

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

  • 02:54: It would actually be really helpful if you’ve already seen our recent video on paradoxes in special relativity.
  • 07:07: This seems paradoxical, but the solution is the same as it is for the twin paradox from our previous episode.
  • 07:27: In the twin paradox, the twin traveling to a nearby star and back has aged less even though both could see the other’s clock ticking slowly.
  • 09:53: ... the case of the twin paradox, gravitational time dilation gives the right relative time flows if you ...

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

  • 13:46: In the process of answering that we explored the ladder paradox and the twin paradox, and that's what our questions are about today.

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

  • 00:35: A cascade of seeming paradoxes.
  • 00:43: ... we’re going to delve into a couple of the most famous paradoxes of special relativity and see why, against our intuition, the universe ...
  • 00:53: But the point of this episode is to go much further - we’re going to try to break the universe by pushing these paradoxes beyond the limit.
  • 01:42: ... seeming contradictions only become paradoxes if the different observers - on the spaceship and on Earth - can compare ...
  • 01:52: ... relative passage of time and the distance traveled - but those aren’t paradoxes because both agree about when the astronaut arrives at their ...
  • 02:18: Let me give you an example of a trickier apparent paradox.
  • 03:00: That would be an unresolvable conflict in the observations - a paradox.
  • 03:05: This paradox was actually presented to me by one of our Patreon supporters - and it stumped me for a while.
  • 03:13: However the resolution requires us to think about two much more famous paradoxes in relativity - the twin paradox and the ladder paradox.
  • 03:21: Let’s start with the twin paradox.
  • 03:57: ... resolution to the paradox lies in the fact that the traveling twin hasn’t been in a single moving ...
  • 04:57: ... can use these lines of simultaneity to solve the twin paradox because they allow us to track the apparent passage of time back on ...
  • 05:53: Let’s first look at the twin paradox in a closed universe.
  • 08:11: Ok, enough with the twin paradox.
  • 08:14: We need one more paradox before we can wrap this up.
  • 08:22: This is the famous ladder paradox.
  • 09:12: The solution to the ladder paradox also relies on the relativity of simultaneity.
  • 10:54: This is a variant of the ladder paradox, but here the doors of the barn map to each other, pacman style.
  • 12:01: Relativity is weird, but its seeming paradoxes always have resolutions.
  • 12:05: ... just need to follow the logic and the paradoxes evaporate, and so we make sense of this deeply strange, but unfailingly ...

2020-12-22: Navigating with Quantum Entanglement

  • 12:25: Instead I'm going to do a whole episode on some of the weirder paradoxes in relativity, that I think will make it all totally clear.

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

  • 00:00: ... well Bob dead in that question just solved the black hole information paradox because that is exactly the proposal that Gerard T Hooft who I ...

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

  • 11:03: ... not yet ruled out its existence, exotic matter threatens horrible causal paradoxes. Many physicists believe it can’t exist, if for no other reason than our ...

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

  • 01:53: ... never happens. It’s like Achilles chasing the tortoise in Zeno’s paradox - Achilles covers half the remaining distance at each step, and so never ...
  • 03:14: ... fuse time with a something called a tortoise coordinate, after Zeno’s paradox. It’s a measure of distance that becomes infinitesimally compact ...
  • 10:20: Confusing. And it’s okay that this doesn’t make much sense - faster than light travel always leads to silly paradoxes because it’s impossible.

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

  • 04:28: ... quantum mechanics. This is the so-called Einstein-Podolsky-Rosen, or EPR paradox. A high energy photon decays into an electron and a positron. These ...

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

  • 12:42: ... light travel can break causality and you'll even solve the famous twin paradox. ...

2019-11-04: Why We Might Be Alone in the Universe

  • 00:22: And perhaps resolves the Fermi Paradox.
  • 03:05: ... Fermi Paradox notes the apparent contradiction between the massive abundance of ...
  • 03:19: Now, we’ve talked about the Fermi Paradox before, and some potential solutions.
  • 03:35: ... solution to the Fermi paradox is often expressed in terms of one or more great filters - extremely ...
  • 12:03: The Fermi paradox surely has a solution, and that solution may be that the galaxy is as empty as it looks.

2019-10-21: Is Time Travel Impossible?

  • 09:53: But there are no true paradoxes – only seeming paradoxes that point to a gap in our understanding.
  • 10:04: It states that the laws of physics will always prevent time travel or allow it only when doesn’t cause paradoxes.
  • 10:17: One way for a closed timelike curve to exist without causing a paradox is expressed in the Novikov Self-Consistency Principle.

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

  • 08:49: Here it is: eternal inflation may solve the Fermi Paradox.
  • 11:13: Guth calls this argument the Youngness Paradox.

2019-06-17: How Black Holes Kill Galaxies

  • 12:04: ... number of people wondered whether the Fermi Paradox might be explained by the fact that neutron star collisions are rare so ...

2019-04-10: The Holographic Universe Explained

  • 02:11: ... discovery of Hawking radiation led to the black hole information paradox, because this radiation was expected to erase the quantum information of ...
  • 02:28: Hence the paradox.
  • 02:47: Nice solution, but new paradox.
  • 12:09: ... things, this provided a new resolution to the black hole information paradox: the information lost in a black hole persists perfectly comfortably in ...

2019-01-24: The Crisis in Cosmology

  • 14:51: that they produce perpetual motion machines and paradoxes left and right.
  • 15:05: explore these paradoxes.

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

  • 13:43: ... week we talked about the latest thinking on the Fermi paradox and what conclusions we can really draw about this persistently annoying ...
  • 13:54: ... few people say that the Fermi paradox isn't really even paradoxical with some common objections about the ...
  • 15:15: The Fermi paradox must be explained by a very long chain of soft filters that add up to extremely small probability or one or more hard filters.

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

  • 00:06: The silence of the galaxy and the resulting Fermi paradox has perplexed us for over half a century.
  • 00:23: [THEME MUSIC] When Enrico Fermi uttered the words, "where is everybody," he was succinctly summarizing what has become known as the Fermi paradox.
  • 00:59: But the paradox is much broader than this.
  • 01:22: The Fermi paradox has become only more paradoxical.
  • 07:08: A number of attempts have been made to address the Fermi paradox based on this new data.
  • 10:23: Our modern understanding of the Fermi paradox permits a second interpretation.
  • 11:56: But even thousands of years is brief enough to help explain the Fermi paradox.

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

  • 03:27: Starting with the mild, we have the black hole information paradox.
  • 03:50: But that same Hawking radiation offers part of the solution to the information paradox.
  • 04:07: In a sense, both the source and the solution to the information paradox came from the discover of Hawking radiation.
  • 16:08: ... is skeptical about the 't Hooft solution to the black hole information paradox and cautions that we don't neglect other interesting ideas, like ...
  • 16:21: Well, to be fair, we did mention complementarity in the information paradox episode.

2018-09-05: The Black Hole Entropy Enigma

  • 01:50: ... back to those episodes where we laid out the black hole information paradox because they're going to be critical to a proper ...
  • 02:30: ... internal quantum information, giving us the black hole information paradox. ...
  • 02:42: Eventually, a possible resolution to this paradox was found by Gerard 't Hooft.
  • 05:19: But if you paid attention to the whole information paradox bit, you might be able to think of a solution.
  • 05:35: Actually, yeah, the resolution to the information paradox also saves the second law of thermodynamics.

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

  • 11:01: In the last two episodes we covered the black-hole-information paradox and asteroid mining.

2018-06-20: The Black Hole Information Paradox

  • 01:06: This is the black-hole information paradox, and it's one of the biggest unsolved problems in physics.
  • 03:56: And that's the information paradox.
  • 04:11: And when Hawking first pointed out the paradox in the mid-70s, physicists were skeptical that there was a real problem.
  • 04:41: ... 15 years behind Hawking, that the accepted principles lead to a truly paradoxical conclusion." So it turns out that if we assume that both general ...
  • 05:05: But there's no such thing as a true paradox.
  • 05:14: The search for the resolution to this paradox has led to some incredible new physics and some pretty astounding ideas.
  • 05:49: This solution to the paradox has been attributed to Freeman Dyson, who was championed by Hawking for many years.
  • 07:07: And two, if it did, it would break quantum mechanics as surely as the old information paradox.
  • 10:45: They are, of course, untested, but black-hole complementarity introduces yet another paradox.

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

  • 01:32: ... result will be the black-hole-information paradox, one of the greatest unanswered questions in modern physics, and also the ...
  • 10:45: Yet Stephen Hawking showed that black holes may break this rule, revealing a conundrum that we now call the information paradox.
  • 10:54: The solution to the information paradox is highly speculative, but it may reveal that black holes are more hairy than we thought.

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

  • 09:54: Stephen Hawking's eponymous radiation appears to destroy quantum information leading to the famous black hole information paradox.

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

  • 00:55: But before we dive into this extremely elegant idea, let's talk about the seeming paradox that inspired it and the genius who discovered it.
  • 01:40: Two of the greats of the era, David Hilbert and Felix Klein, sought the help of a young mathematician Emmy Noether to understand this seeming paradox.

2018-03-15: Hawking Radiation

  • 11:32: ... then there's the famous information paradox in which Hawking radiation appears to destroy what should be a conserved ...

2018-01-24: The End of the Habitable Zone

  • 05:36: ... prediction and the geological evidence is called the faint young sun paradox, and was pointed out by Carl Sagan and George Mullen in the early ...
  • 06:12: However, there is not yet a consensus on the exact solution to this paradox.

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

  • 04:39: Your ship, the Paradox, can travel at twice the speed of light.
  • 05:09: Meanwhile, your own world line remains on Earth as you build the paradox.
  • 05:47: And now that you've mastered faster-than-light travel, can you pilot the Paradox back to a point before the race even started?
  • 06:45: ... can figure out the paradox world line because we know which spacetime interval contours it's on ...
  • 06:55: The Paradox still appears to be traveling forward in time with respect to the Annihilator, even though it's traveling faster than light.
  • 07:14: The Paradox outraces its own photons as it catches up to the Annihilator, and then it continues to emit light backwards behind it after it passes.
  • 07:31: The Paradox appears to materialize out of nowhere and then proceeds to split in two.
  • 07:38: One Paradox seems to race onwards towards its destination, while the other travels in reverse back towards Earth.
  • 07:46: ... travel, but a physicist on the Annihilator would still infer that the Paradox is moving forward in time, upwards according to the Annihilator's own ...
  • 08:09: ... we transform the diagram to their perspective, we see that the Paradox really does appear to travel backwards in time according to this new ...
  • 08:22: Well, no, not if we can find a way to bring the Paradox back to a point in space before it was built.
  • 08:42: We can keep flying the Paradox until we cross this ominous 45 degree boundary.
  • 09:02: In that frame, the Paradox has moved into a region that appears to be prior to the start of the race.
  • 09:14: ... we travel far enough, then when we finally turn the Paradox around, it's twice lightspeed movement will take us back to the ...

2017-03-08: The Race to a Habitable Exoplanet - Time Warp Challenge

  • 03:04: Happily, medical technology developed faster, and you live long enough to paint the name Paradox on its gleaming hull.
  • 03:13: With the Annihilator still only halfway to its destination, the Paradox will easily overtake it and win the race.
  • 03:23: What does the captain of the Annihilator see at the moment the Paradox overtakes?
  • 03:40: When you transform the diagram to the perspective of the Annihilator, the paradox should suddenly appear to act like a time machine.
  • 03:57: ... first part of the Annihilator's journey during the construction of the Paradox, then they transform to the Annihilator's perspective like ...
  • 04:21: ... a spacetime trajectory that allows you to fly the Paradox all the way back to the beginning of the race, the beginning in both ...

2017-02-02: The Geometry of Causality

  • 00:11: When time is relative, paradoxes threaten.

2016-11-16: Strange Stars

  • 13:09: ... do that, I'm going to have to go through the black hole information paradox, Hawking radiation, some string theory, the holographic principle, other ...

2016-10-26: The Many Worlds of the Quantum Multiverse

  • 03:36: Many adherents to Copenhagen now have a more sensible resolution to the paradox of Schrodinger's cat.

2016-09-29: Life on Europa?

  • 11:50: ... John Stewart Bell had another possible solution to this whole seeming paradox-- that is super ...

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

  • 03:13: The Einstein Podolsky Rosen, or EPR, paradox introduces one of the most mysterious ideas in quantum mechanics-- quantum entanglement.
  • 10:15: The universe seems to conspire to avoid the paradox of information traveling faster than light, or backwards in time.

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

  • 01:21: So we get back to the famous Fermi Paradox.
  • 01:24: ... suggest that the resolution to this paradox is that advanced civilizations never make it to an interstellar state, ...
  • 06:41: This brings us back to the Fermi paradox.

2016-08-24: Should We Build a Dyson Sphere?

  • 09:40: Either way, Fermi paradox solved.

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

  • 11:33: A few of you rightly know that quantum mechanics isn't needed to resolve Zeno's paradox of Achilles and the tortoise.
  • 11:41: ... infinite divisibility of space was a problem with the scenario in this paradox, that the real resolution is that there are different types of ...
  • 12:54: ... of you noticed that the tortoise we used in Zeno's paradox is actually a turtle, and not just any turtle, but Great A'Tuin, the ...

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

  • 00:38: Zeno's famous paradox tells us that it's impossible to overtake a tortoise.
  • 01:05: There are a few problems with this paradox, but one is that it assumes that space is infinitely divisible.

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

  • 00:56: Paradoxically, our measurements points a near-perfect flatness.

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

  • 10:14: So a lot of you independently realized that the time dilation of special relativity seems to generate a paradox.
  • 10:40: This is a famous problem call the twin paradox.
  • 10:54: The resolution is that there is no such thing as a paradox.
  • 10:58: If you see an apparent paradox, it means that you're missing something.

2015-11-18: 5 Ways to Stop a Killer Asteroid

  • 08:31: ... In a recent episode we talked about the origin of life and the Fermi paradox. ...
  • 10:06: And so it makes the Fermi paradox even more paradoxical.

2015-11-05: Why Haven't We Found Alien Life?

  • 00:43: ... Way so un "Star Warsy?" This genuine oddity is referred to as the Fermi paradox and the resolution for it has to be that there's some sort of great ...

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

  • 10:11: The universe is an infinitesimal here-and-now This is all pretty paradoxical.
  • 10:19: However, the paradox itself tells us that an infinite speed limit is impossible.

2015-02-25: How Do You Measure the Size of the Universe?

  • 05:50: ... real point of Fermi paradox is that colonization on a galactic scale could happen so quickly that if ...

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

  • 04:51: And it now bears his name, the Fermi paradox.
  • 05:02: Now you can, of course, explain the Fermi paradox away.
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