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2022-12-08: How Are Quasiparticles Different From Particles?

  • 07:21: You can think of sound as a coherent beam of phonons, like a laser, while heat is a random buzz of phonons.
  • 09:49: But of course we have them pesky phonons, which at any significant temperature just add up to a lot of random jiggling of the atoms - AKA heat.
  • 10:22: Very low temperature means few random, noisy phonons.

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

  • 18:11: While you can trust much of what I say, there are a few areas where you should not entirely rely on some random astrophysicist on YouTube.

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

  • 17:35: ... that all other things equal, an observer should reason as if they are randomly selected from the set of all actually existent(past, present and future) ...

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

  • 19:08: ... Martinez asks if there’s a problem using a random number generator to decide measurement direction, considering that true ...

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

  • 09:33: Aspect found a way to randomize measurement direction without moving the polarizers at all. The trick was to use a type of transducer.
  • 09:54: ... electrical switch - a switch that could be turned on and off quickly and randomly in the tiny interval between the creation of the photon and their ...
  • 11:00: But what if the random number  generator wasn’t really random?
  • 11:05: ... all, signals could have travelled to both the calcium atom and the random number generator from some common influence, causing them to ...
  • 11:16: ... the particles are not only correlated with each other, but also with the random number generator or the physicist choosing the measurement ...

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

  • 08:41: Many physicists believe that these constants  were set more or less randomly at the beginning of the universe.
  • 12:17: ... about it this way - if the constants of nature were set randomly at the big bang, and were set independently to each other -  then ...

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

  • 00:36: ... vacuum of space has a constant energy density. Empty space buzzes with random activity that we sometimes describe as virtual particles popping into ...

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

  • 10:18: ... method   in which you do your calculation based on  randomized selections from some ...
  • 10:43: ... we randomly choose a selection of  field configurations of a pixelated ...
  • 16:44: ... gloves, put them in separate sealed boxes and give one to a friend randomly. When you look in   your box and see that it’s the left glove ...

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

  • 10:06: It assumes that Alice and Bob can choose with absolute freedom, or that if they choose randomly, that their random number generator is perfect.
  • 12:35: ... “random” color of individual photons of that light was used in place of a random ...

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

  • 04:44: ... the no-hair theorem,   Hawking radiation should be completely random. It should contain no information about anything   besides the ...

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

  • 05:53: ... deflected left or right - its undefined  left-right spin chooses randomly between the two   because it contains no information about its ...

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

  • 02:19: ... envelopes - an elongated   spheroid of stars that all orbit randomly at  different angles. All of this is surrounded by the   ...

2022-04-27: How the Higgs Mechanism Give Things Mass

  • 05:38: ... These magnets have high temperature which makes   them move randomly, but as the system cools down  this random thermal motion gets ...
  • 06:43: ... but if the  ball starts at the top of the hill it will   randomly roll down into one valley.  Now the current state of the ...
  • 11:02: ... of  this little hill, but then quickly roll down in   a random direction. The new state of the field  would not be symmetric to ...
  • 12:26: ... states.   The universe will just have  chosen one state randomly.   But the field can also oscillate along the base of  the valley in ...

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

  • 01:59: ... have a cat in a closed box that is either killed or not killed by a random quantum process. For a scientist running the experiment, the cat is in a ...
  • 05:56: ... we add a pair of detectors we see that each photon randomly arrives in detector 1 or detector 2, revealing whether it was ...
  • 08:42: ... with. Instead, she answers the quest ions as they come, maybe completely randomly, maybe according to some secret pattern. Every answer narrows the space ...

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

  • 00:25: ... the cosmos until Nicolaus Copernicus shoved us from our pedestal onto a random rocky planet orbiting an ordinary star in the outskirts of an ...
  • 07:27: Now imagine that 2-D dweller points at a random direction.
  • 08:27: ... you can still point at the Big Bang by pointing in a random direction, because the line traced from you finger also ends up at the ...

2022-02-23: Are Cosmic Strings Cracks in the Universe?

  • 04:51: ... jiggle would send the ball,   or the Higgs, rolling down in a random direction.  And that’s what happened. Here and there ...
  • 05:59: ... field formed strings. Remember   that the vacuum decayed in a random  direction towards this circular valley.   That means we can ...

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

  • 06:22: ... of this non-linear action as a rare and random hit that the wave function takes at a particular location. That hit ...
  • 08:02: ... In CSL, physicists imagined that the localizing mechanism was a randomly jiggling field, like the frenetic Brownian motion of pollen grains ...
  • 09:25: ... in the Schrödinger equation, causing the wave function to rapidly and randomly choose to make the object appear either “here” or “there,” but not ...
  • 11:09: ... For example, the models imply that a quantum wave function will be randomly tossed about and jostled by gravity or some other collapsing field. If ...
  • 18:37: ... its original formulation Hawking radiation is supposed to be completely random - information free - and so that when a black hole evaporates all the ...

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

  • 03:17: ... previously, but the TL;DW is that Hawking radiation should be completely random, and so leaks away the black hole’s mass without any of the information ...

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

  • 08:39: ... with some being more probable than others. The particle then appears to randomly select a position from that ...

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

  • 12:30: ... particles even travel at all or do   their wave functions just randomly tunnel every  which way so that their apparent path is ...

2021-08-18: How Vacuum Decay Would Destroy The Universe

  • 10:10: ... only a very small probability  that a bubble of true vacuum will randomly form   that’s large enough to actually continue  growing. ...

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

  • 17:57: ... Asimov attribution first appeared in fortune, a random quote generator program in UNIX - so a totally reliable source. I got ...

2021-07-21: How Magnetism Shapes The Universe

  • 06:29: The light gets polarized - which means the direction of its electric and magnetic fields pick up a preferred direction rather than being random.

2021-07-13: Where Are The Worlds In Many Worlds?

  • 04:04: ... measurements appear to be randomly selected based on the current state of the wavefunction - more likely ...
  • 05:22: ... only the outcome that was measured - and that value is selected randomly, but weighted by the pre-measurement ...
  • 05:42: ... causes this random selection is not the Schrodinger equation - it’s something extra, and ...

2021-07-07: Electrons DO NOT Spin

  • 05:37: ... field should be deflected by less. So a stream of silver atoms with randomly aligned magnetic  moments is sent through the magnetic ...
  • 06:10: ... maximum, but most  deflected somewhere in between due to all the random orientations. But that's not what’s  observed. Instead, the atoms ...
  • 15:09: ... Randomaited asks the following: If entropy only increased over time, which implies ...

2021-06-23: How Quantum Entanglement Creates Entropy

  • 07:44: ... state.   Rather it changes the quantum state in a  random way - now 100% heads or 100% tails,   but the information ...

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

  • 02:38: ... number comes out pretty small - around 10^-35 m. But why is this random-seeming   combination of constants so important? Well, it represents the ...

2021-05-19: Breaking The Heisenberg Uncertainty Principle

  • 09:05: Less flickering due to random phase shifts means that we can see real signals due to much weaker gravitational waves.

2021-04-21: The NEW Warp Drive Possibilities

  • 18:08: ... number of worlds where the freezing of cryptochrome quantum states randomly failed in all avian ...

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

  • 09:14: There's roughly a one in 10,000 chance that random fluctuations could lead to that degree of difference just by chance.
  • 09:25: For five-sigma, there's only one in 3.5 million chance of random noise resulting in the same signal.
  • 10:35: It really was just a random statistical fluctuation.
  • 11:00: The chance of randomly getting a 4.2 fluctuation is just a little over one in a 100,000.

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

  • 00:36: ... comes from the idea that electrons in atoms jump randomly and instantaneously from one orbit or energy level to another, without ...
  • 02:41: Copenhagen describes transitions in quantum states as fundamentally random - the dice are rolled, and the system transitions instantaneously.
  • 04:34: It was a reaction against one of the central tenants of Copenhagen - that subatomic phenomena are fundamentally random, or probabilistic.
  • 06:46: If the electron then falls back to level 1 it should emit an identical photon in a random direction.
  • 08:02: And the downward jumps when the electron decayed out of level 3 appeared to occur at completely random times.
  • 08:16: ... the jump appeared random, there was no way to tell whether it was instantaneous, or whether the ...
  • 09:55: But what about the randomness of the event?
  • 09:57: Well, the spacing between events did appear to be random, as Bohr thought.
  • 10:19: ... driven by an underlying deterministic mechanism, rather than fundamental randomness. ...
  • 12:06: ... and perhaps even whether the quantum world is built upon fundamentally random processes, or is driven by rigidly deterministic mechanic of space ...

2020-12-08: Why Do You Remember The Past But Not The Future?

  • 06:45: ... pass through in exactly the right way to erase their tracks, seemingly random quantum jiggling ejects these embedded clumps, and so on, until we’re ...
  • 12:23: ... of matter and energy in the early universe does appear to have been random - which we normally associate with high ...
  • 13:18: Ryan Christopherson asks whether the random nature of quantum mechanics isn’t a larger hurdle to the reversibility of time than entropy.
  • 13:33: ... answer is that yes, IF quantum mechanics is fundamentally random, and IF the wavefunction collapse is a random rather than deterministic ...
  • 13:47: ... personally don’t hold with random collapse interpretations, and at any rate invoking random collapse ...

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

  • 03:53: ... shared out and it would stay shared out. It’s very unlikely that through random collisions, half the electrons would get all the energy and the other ...
  • 04:13: ... if you start from a situation where energy is not perfectly randomly spread out, then over time it’ll become more spread out. Entropy ...
  • 05:10: ... particles in one spot in the available space. Let’s give those particles random velocities and see what happens in the following time steps.Even though ...
  • 05:43: ... this look like going backwards in time? Uh, exactly the same actually. Random velocity directions will tend to spread this cluster apart in both time ...
  • 06:57: ... decrease very occasionally and, typically, on very small scales due to random alignments of particle trajectories or however else energy is moving ...
  • 07:17: ... particles across our universe - in the form of galaxies - we don’t see random motion. We see galaxies racing away from each other, which means they ...
  • 08:11: ... in time to this original “special” slice, at which velocities are all random, and keep tracing out the other side then you should see entropy ...
  • 11:16: ... as the universe evolves. But we can think of that initial event as a random number generator whose gigantic store of random numbers are then used ...

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

  • 02:26: ... the outcomes of quantum-scale events are fundamentally random or the outcomes of quantum events are perfectly determined by quantum ...
  • 04:45: ... mechanistic process, whether that process is deterministic or random. ...
  • 05:47: The Copenhagen interpretation insists that the apparent randomness of quantum events is really random.
  • 06:08: ... idea of random processes driving our choices doesn't really sound like free will, so is ...
  • 06:32: ... bit of information being intentionally, say, a one or a zero rather than randomly a one or a ...
  • 06:46: ... arises within our packet, within our brain, then either it itself is random or has its own causing thread whose origin is either in our brain and ...
  • 07:12: The only way for new information to come from a closed region is for it to be generated randomly within that region.
  • 07:19: On the surface, the idea of randomly generating new streams of quantum information within a brain doesn't seem to help the cause of free will.
  • 08:16: ... go into making it, either in principle or in practice, because unknown random processes are at work, and/or perfect measurement is not possible for ...
  • 09:24: By the way, there's also evidence to indicate that brain activity utilizes the random fluctuations of neuronal activity to make certain decisions.
  • 09:33: In other words, a certain type of randomness may be a feature of the brain, an item in its mechanistic toolbox.
  • 09:40: ... the all-knowing Laplace demon may be out of luck, especially if quantum randomness or quantum indeterminacy is magnified to brain-level ...
  • 11:37: ... generating this phenomenon, which is founded in either deterministic or random processes, then the phenomenon is an ...

2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces

  • 10:03: ... the Curie temperature - thermal energy causes the particles to rotate randomly so the overall magnetization of the material is ...
  • 10:30: Even though the equations of motion say one direction is not preferred to the other, the ground state has randomly picked out a single direction.

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

  • 13:38: ... when a boltzmann brain is the simplest  explanation.” You’re just random particles   accidentally assembled from the void with ...

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

  • 04:23: ... quantum mechanics but at the moment of measurement, a single reality is randomly selected from the distribution of possible ...
  • 05:17: The illusion of randomness is that we find ourselves in the one branch of the wave function, corresponding to the reality we perceive.
  • 05:25: But we aren't randomly placed in that branch, we just are a part of that branch.

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

  • 14:22: ... although those atoms to reemit the absorbed energy, they do so in random directions AND potentially through a cascade of energy level drops that ...

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

  • 00:00: ... brain there right there would be if everything just looked completely random you couldn't make any predictions anyway so why have a brain uh so ...

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

  • 04:40: ... away from us due to the expansion of the universe - they also have random motion as they’re tugged by the gravitational fields of nearby galaxies ...

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

  • 00:00: ... and the radiation produced by black holes would be this totally random thermal glow okay of radiation which should contain none of the ...

2020-04-14: Was the Milky Way a Quasar?

  • 09:54: A mini AGN phase is triggered either by an influx of gas or by a random massive star getting too close to the black hole.

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

  • 12:36: ... massively multiplayer online game, where players can battle others at random or play cooperative battle types, battling against bots or in a ...

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

  • 03:12: ... you’d expect for a classical spinning object. Instead the electron will randomly shift ot having left or right ...
  • 15:50: ... of "yourself". If by that you mean any given version of you chosen randomly from all possible future timelines - then yes, chances are that version ...
  • 16:29: ... an entropy fluctuation large enough to produce a new big bang? Could a random perfect alignment of all particle trajectories produce a big bang ...

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

  • 02:33: ... a totally random 50-50 chance of the radioactive decay over a certain period of time - ...

2020-02-24: How Decoherence Splits The Quantum Multiverse

  • 08:05: ... by those particles, and so the wavefunction leaving that slit picks up a random phase offset compared to the other ...
  • 08:18: ... that emerging wavefunction can still interfere with itself - the random phase offset would just shift the pattern left or right for that ...

2020-02-11: Are Axions Dark Matter?

  • 05:16: ... ended up very close to zero just by chance, but physicists hate using random chance to explain the precise refinement of a value - what they call ...

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

  • 01:15: ... heard the old thought experiment - if an infinite number of monkeys tap randomly on an infinite number of typewriters, eventually one of them will ...
  • 01:30: The reasoning is simple enough: assume each monkey is tapping at all keys randomly.
  • 03:38: The properties of each region are effectively random - set in the beginning of the universe by quantum processes.
  • 08:40: For example, you could argue that fundamental quantum randomness will cause even identical starting configurations to produce different results.
  • 09:00: In fact, quantum randomness could allow different starting conditions to evolve into a universe that looks like this one.
  • 11:31: Turns out monkeys don’t hit all keys randomly.

2020-01-20: Solving the Three Body Problem

  • 10:30: ... thing about chaotic motion is that the state of the system seems to get randomly shuffled over time. The motion is actually perfectly deterministic - ...

2020-01-13: How To Capture Black Holes

  • 04:50: ... of stellar mass black holes? The orbits of those black holes are mostly random, so the swarm forms a spheroid a few light years across. The accretion ...

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

  • 02:10: ... fundamental constants of the daughter universes are shifted slightly and randomly from their parent - mutations are ...
  • 04:34: ... one thing: what if, when universes reproduces, the constants aren’t randomly reconfigured but rather change only slightly - analogous to a small ...
  • 05:24: ... given universe may not be totally optimal because its constants varied randomly from its parent - in the same way that any given living organism isn’t ...
  • 15:20: ... point is if any given individual assumes that we're randomly sample from all generations who thought about the doomsday argument then ...
  • 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.

2019-12-09: The Doomsday Argument

  • 04:15: ... “All other things equal, an observer should reason as if they are randomly selected from the set of all actually existent observers (past, present ...
  • 09:51: ... and doom-late are both thought of as existent, so that you can be randomly plucked from one - in the same way the two boxes ...
  • 10:07: ... presumably only one is true and you weren’t randomly plucked from it - you just are what you are - a being with a mental ...

2019-12-02: Is The Universe Finite?

  • 08:46: A random distribution of blobs ends up with slight clusterings.
  • 09:19: ... a flat universe would look like a positively curved universe just due to random ...
  • 14:35: ... do you choose the sample of observers from which you consider yourself randomly ...

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

  • 07:25: There are more typical environments than non-typical ones, so pick a random environment and its probably typical.
  • 09:08: ... the assumption that our universe resulted from a simple random fluctuation in an otherwise high-entropy cosmos, the anthropic principle ...
  • 09:23: Apparently we aren’t, and so we can probably rule out a simple random entropy fluctuation as a sufficient explanation for our big bang.
  • 10:08: ... that “All other things equal, an observer should reason as if they are randomly selected from the set of all actually existent observers (past, present ...
  • 15:26: ... - perhaps the dials defining the fundamental constants were neither randomly set nor deliberately ...

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

  • 00:38: The anthropic principle tells us that we shouldn’t expect to find ourselves in some random corner of the multiverse - there’s an observer bias.

2019-09-03: Is Earth's Magnetic Field Reversing?

  • 02:32: In fact these flips seem to be pretty random events.
  • 07:13: Well, actually ANY weak field – even random bits of field – for example thermal fluctuations - are enough to initiate this runaway effect.
  • 08:50: ... magnetic field were switched off entirely, it would reestablish itself randomly, with the north and south magnetic poles aligned either one way or the ...
  • 09:18: It then builds up again, choosing its direction randomly.

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

  • 04:02: The random nature of this version of inflaton decay means that many such bubbles should form, ie. multiple universes exist.
  • 05:07: But it wouldn't end as a random process, it wouldn't require quantum tunneling to get started.
  • 06:49: I mentioned that quantum fields fluctuate due to the intrinsic randomness of the quantum world.

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

  • 08:29: ... if the inflaton field stays stuck. But quantum fields have a tendency to randomly fluctuate to different values, thanks to the Heisenberg uncertainty ...

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

  • 11:12: ... infinite time or The same amount of time could lead to all particles randomly converging back to the same spot Or maybe black holes birth new ...

2019-06-17: How Black Holes Kill Galaxies

  • 00:08: ... between the Black Hole mass and the speed that stars are moving in their random orbits within galactic bulge the so called, Stellar Velocity ...

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

  • 05:48: ... for example, pass a randomly-polarized photon through a horizontal polarization filter like a polarized ...
  • 07:43: ... generates a random string of bits, 0’s and 1’s and encodes these bits using photons ...
  • 07:58: These bits are then sent over an open channel to Niels who then randomly picks a basis of his own for each photon and projects onto that.
  • 08:07: ... i.e. Albert sent a 1 and Bob also gets a1, otherwise he will get a random result – Albert sends a 1 but Niels will get a 1 or 0 with equal ...
  • 08:22: Over that same public channel they randomly pick a subset of those bits and Albert reveals which basis was used for those photons, and what she sent.
  • 08:33: If Niels used a different basis he ignores the result because he knows it will be random.
  • 09:06: That’s because Werner, like Niels, can only pick a random basis each time on which to project the photons.
  • 09:14: ... photon state is unchanged, otherwise it will project the photon onto a random state, meaning Niels isn’t guaranteed to get the same answer as Albert, ...
  • 12:18: Niels chooses a random set of bases to measure the particles he receives.
  • 17:05: Randomly hearing that while walking down the street would creep me out too much.

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

  • 00:03: ... okay to the face mollify shares with us they're tuning in to that video randomly was like Oh bleep I just walked into the final exam without ever going ...

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

  • 09:34: Now there is a bit of variation in the relationship between UV and X-ray brightness – there’s random scatter.
  • 13:36: ... few very distant quasars with good X-ray measurements, so maybe the random variations in the UV-to-X-ray ratio by chance to gave a false ...

2019-03-13: Will You Travel to Space?

  • 14:05: Now to remind you, the Brownian ratchet has this flywheel that turns a cog due to random motions of particles hitting the flywheel.
  • 14:38: ... vibration. Even in a vacuum, that internal vibration is enough to randomize its rotational ...

2019-03-06: The Impossibility of Perpetual Motion Machines

  • 04:00: Individual gas particles are moving around with random – or Brownian motion.
  • 06:55: Due to the intrinsic quantum randomness of all particles, as expressed by the Heisenberg uncertainty principle, everything moves.

2019-02-20: Secrets of the Cosmic Microwave Background

  • 00:08: ... early Universe became transparent for the first time It sounds like random static But that buzz contains an incredible wealth of hidden information ...
  • 12:34: ... background It's an insane wealth of information f rom what looks like random minuscule fluctuations in this faint noisy buzz So next time you hear ...

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

  • 03:51: ... teensy bit less there, These fluctuations probably were the remnants of random quantum fluctuations From when the universe was subatomic in ...
  • 08:35: Collapse that web into galaxies over the age of the universe, and at first glance, it looks like a random smattering of galaxies on the sky.
  • 09:18: With a galaxy redshift survey in hand, how do you find patterns in what looks like a random splattering of tens to hundreds of thousands of galaxies?

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

  • 14:07: 6 randomly selected correct-slash-creative answers will receive their choice of any piece space time swag from our brand new merchandise store.

2019-01-24: The Crisis in Cosmology

  • 10:13: ...that that level of difference could have happened through random errors.

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

  • 00:02: ... a directed panspermia program gives you much better numbers than randomly scattering with the philic bacteria from asteroid impacts with a non ...

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

  • 00:37: ... months although it's more likely to take years or centuries given the random nature of the journey those timescales are totally reasonable for the ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 08:26: And finally, what about the sheer unlikelihood of a random encounter with an interstellar space rock?
  • 10:24: And that's a pretty typical speed for a random object orbiting in the Milky Way.

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

  • 10:27: ... particles." The quantum state is not fluctuating on its own, but it will randomly collapse into one of these possibilities when something interacts with ...

2018-10-10: Computing a Universe Simulation

  • 10:58: We chose six correct enough responses at random listed below.

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

  • 14:43: The actual amount of time it takes to decay is random, and there's a constant probability of it happening at every set interval.

2018-09-05: The Black Hole Entropy Enigma

  • 03:55: The higher the entropy, the more randomly distributed its particles and the more possible configurations lead to the same macroscopic state.
  • 04:12: ... which means energy tends to spread out evenly and particles tend to randomize, reducing our information about their microscopic ...
  • 04:36: Now that's a high entropy based, super hot and full of randomly moving particles.
  • 09:04: He showed that black holes radiate random particles exactly as though they have a peak glow for a particular temperature that depends on their mass.

2018-08-23: How Will the Universe End?

  • 04:49: As stars randomly pass close to each other, planets are flung into the blackness.
  • 07:44: They slowly leak away their mass as a cool heat [INAUDIBLE] of random particles for the most part faint radio light.
  • 16:20: ... says that sometimes it feels like we're trying to fit maths randomly to the observations when we come up with stuff like virtual particles ...
  • 17:01: The key is that our accepted models of reality are consistent in ways that random chance couldn't possibly allow.

2018-08-01: How Close To The Sun Can Humanity Get?

  • 09:23: 25 random participants will receive an awesome PBS DS t-shirt.

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

  • 00:15: Entropy is sometimes described as a measure of disorder or randomness.
  • 00:50: But entropy is connected to disorder and randomness in a very real way.
  • 02:04: Let's say we place 180 black stones on random vertices of our Go board.
  • 07:34: From our point of view, the randomness of the particles decreases, but that randomness is transferred to the memory of the demon.
  • 09:53: It can be interpreted as the amount of previously hidden information that can potentially be revealed by the observation of a random event.

2018-07-18: The Misunderstood Nature of Entropy

  • 05:18: So if you look at the system at some random point in time, it'll be in a completely random microstate chosen from all possible microstates.
  • 05:38: Let's say you place 180 black stones at random.

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

  • 03:18: The position that we observe when we look at the particle is picked randomly from that distribution.

2018-06-20: The Black Hole Information Paradox

  • 02:44: ... causes black holes to evaporate into a perfectly random buzz of radiation that contains none of the information about the ...

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

  • 12:54: Peter K. asks how the universe can be deterministic given the fundamental probabilistic random nature of the quantum world.
  • 13:02: Well, the key here is that that randomness arises at the level of observation.

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

  • 07:58: But all of this talk of quantum mechanics being deterministic seems a bit at odds with the idea of quantum randomness and the uncertainty principle.
  • 08:12: That value seems to be chosen randomly based on the probability distribution encoded in the wave function.

2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!)

  • 01:07: The particles that make up any system all have some degree of random motion.
  • 01:13: That random motion tends to drive the system towards the most common arrangement of particles.
  • 01:18: Such a random disordered, unspecial arrangement is a high entropy state.
  • 06:20: These systems are doing their best to obey the second law of thermodynamics by redistributing their energy as evenly and randomly as they can.
  • 08:01: The most random possible form for energy is thermal radiation, and the lower the energy of its component photons, the higher the entropy.
  • 08:58: Self-replication randomizes the environment, even if each new replicator is highly ordered.
  • 10:10: ... the process of redistributing energy into the most random possible state, little eddies of order, like galaxies, stars, planets, ...

2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor

  • 06:16: It may come from a vast population of random debris floating around in interstellar space.

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

  • 09:17: So we randomly selected six correct answers as winners of the challenge.

2017-08-30: White Holes

  • 10:09: We actually did talk about a case where a random drop in entropy lead to something very much like a white hole in this episode.

2017-08-10: The One-Electron Universe

  • 10:16: We randomly selected five correct answers.

2017-08-02: Dark Flow

  • 00:51: The random motion of galaxies-- what we call peculiar motion-- should also have no preferred direction.

2017-07-26: The Secrets of Feynman Diagrams

  • 11:34: We'll randomly choose five correct answers to win a "Spacetime" t-shirt, and that includes a choice from brand new t-shirt designs.

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

  • 13:01: There are smaller cooler regions that are consistent with random fluctuations.

2017-06-07: Supervoids vs Colliding Universes!

  • 02:22: We think that they came from random quantum fluctuations from the very first instant after the Big Bang.
  • 03:06: Now, it's possible to explain the cold spot as just an unusually strong random fluctuation in the CMB.

2017-05-17: Martian Evolution

  • 02:40: ... a genetic trait is no longer useful, then random mutations will gradually destroy it, like sight and pigmentation for ...

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

  • 08:01: ... an infinite multiverse, it should be vastly more common for particles to randomly assemble into a brain that is having exactly your current experience of ...
  • 13:52: ... that the Boltzmann brain thought experiment fails because it assumes random particle motion, and that particle motion is actually ...
  • 14:09: ... even in a perfectly deterministic universe, there's a pseudo randomness that arises due to massive complexity, say, in a room full of 10 to the ...
  • 14:20: ... there's a pretty powerful emergent force, then even the pseudo random assembly of a Boltzmann brain is vastly more probable than the pseudo ...
  • 16:13: It's also possible to imagine this happening randomly, albeit with stunningly low probability.

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

  • 00:10: You just came into being randomly out of the chaotic void.
  • 00:44: He showed that the laws of thermodynamics can be explained by thinking of gas as a collection of microscopic particles in constant, random motion.
  • 02:32: The air molecules are moving randomly, and over time they pass through all possible arrangements that they could have.
  • 02:39: In most of those random arrangements, the room is filled pretty evenly, and we can't tell those arrangements apart from each other.
  • 02:54: ... of those possible distributions, all of the air molecules end up randomly bunched together in one corner or, I don't know, produce a density wave ...
  • 03:18: Entropy increases because particle positions and velocities get randomized over time.
  • 03:45: The larger the random dip in entropy, the less probable it is.
  • 03:52: ... of gas will happen to all end up in one corner of the room, due to their random ...
  • 04:42: However, there's one arrangement that those particles could randomly fall into that would be even less probable than all of the above.
  • 04:50: All the particles in a region much larger than our universe could randomly end up in almost the exact same location.
  • 08:10: ... experiment I do may be the randomly assembled delusion of a Boltzmann brain that happened to come into ...
  • 09:37: And, in this case, there is no evidence that the Big Bang arose from a random fluctuation.

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

  • 10:43: If you see your name below, we randomly selected your correct answer to win a spacetime t-shirt.
  • 11:20: It should only take about 10 minutes, and we'll be giving away PBS shirts to 25 randomly selected participants.

2017-03-15: Time Crystals!

  • 02:16: Normal matter that is in what we call thermal equilibrium only has random internal motion.
  • 02:26: But from one instant to the next, that buzz stays random.
  • 04:19: Either direct alignment or opposite alignment are both a lower energy state than random alignment.
  • 05:09: ... or continue oscillating at least for a while if the input EM field is randomized. ...
  • 08:51: ... doesn't take much random motion from heat to scramble a carefully prepared array of entangled ...

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

  • 10:02: If you see your name below, we randomly selected you from the correct submissions.

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

  • 15:57: In the Copenhagen interpretation, the uncertainty principle describes the intrinsic randomness of the quantum world.

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

  • 02:36: ... were a measurement to be made, and that upon measurement fundamental randomness determines the properties of, say, the particle that would emerge from ...
  • 03:07: Einstein famously hated the idea of fundamental randomness.
  • 04:51: ... the choice of path isn't random-- if you know the exact particle position and velocity at any point, you ...
  • 05:01: Apparent randomness arises because we can't ever have a perfect measurement of initial position, velocity, or other properties.

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

  • 04:45: The Copenhagen interpretation says that this selection happens in a fundamentally random way.
  • 10:23: It explains the apparent randomness of quantum mechanics with a sort of observer bias.

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

  • 07:36: ... random events that led to technological life dominating the Earth could have ...

2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer

  • 04:41: That decision is made randomly by a beam splitter in the original experiment.

2016-08-17: Quantum Eraser Lottery Challenge

  • 03:11: ... section-- so C and D. That choice is made by these beam splitters, which randomly reflect 50% of photons and let 50% pass ...
  • 03:57: This conscious choice should be no different to the random decision of the beam splitter.

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

  • 10:57: AFastudiousCuber asks, how can something be "fundamentally" random?
  • 11:15: ... function collapses, the properties of the resulting particle are picked randomly from that probability ...

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

  • 09:25: ... that final choice of the experiment of the universe is fundamentally random within the constraints of the final wave ...

2016-07-20: The Future of Gravitational Waves

  • 01:54: It's calculated that LIGO would need to observe for over 200,000 years to see the same signal arise from random vibrations.
  • 02:01: Or another way to put this is that there's a one in 20 billion chance that this signal was from random vibrations.
  • 02:27: There's only a one in 10 billion chance of this one just being due to random noise.
  • 07:40: We chose three random correct answers from both the main and extra credit questions-- names listed right here.

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

  • 03:10: Heat is just the energy in the random motion of particles comprising an object.

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

  • 11:45: ... to become a set of physical properties, there needs to be a completely random sampling of its probability ...

2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners!

  • 02:28: And it could have been the natural result of random fluctuations.
  • 12:40: If your name appears on screen below me, you got this right, and were randomly selected to receive a space time T-shirt.

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

  • 06:07: I'll choose three correct answers at random for both the main and the extra credit questions to receive Space Time t-shirts.

2016-03-30: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners!

  • 00:38: And it could happen pretty randomly over this sky.

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

  • 10:59: And random orientation orbits give you a spheroid.
  • 11:08: Stars a small enough, compared to the distances between them, that they can be in these random orbits.

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

  • 10:52: You'll find the link to the survey in the description, and 25 participants will be chosen at random to win PBS Digital Studios t-shirts.

2016-03-09: Cosmic Microwave Background Challenge

  • 03:53: We'll randomly select three correct answers for each of the two questions.

2016-02-17: Planet X Discovered?? + Challenge Winners!

  • 02:20: Now, the alignment of those weird Kuiper Belt orbits is pretty unlikely to have happened randomly, a 0.007% chance, to be precise.
  • 07:30: We chose three random entries from those to get brand new "SpaceTime" t-shirts.

2016-01-20: The Photon Clock Challenge

  • 01:44: ... choose five random entries from the correct submissions to receive brand-new PBS Space Time ...

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

  • 07:33: We chose five those correct answers at random to receive PBS Digital Studios t-shirts.

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

  • 02:41: We'll select five random correct answers to receive PBS Digital Studios t-shirts, and I'll have the solution for you in a couple of weeks.

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

  • 08:26: Was this a random lucky event that we just had to wait for?
  • 09:00: Of course, maybe the emergence of intelligence is a random and unlikely event, and this one is the hardest to assess.

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

  • 02:02: But a lot of you did submit algebraically correct complete solutions, from which we selected five randomly to win a T-shirt.

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

  • 03:48: Now from among the correct answers, we will randomly select five people to receive a PBS Digital Studios T-shirt.
  • 05:04: Five random people with correct answers and explanations will receive a T-shirt.

2015-06-17: How to Signal Aliens

  • 10:45: ... people who got it right with the correct answer and were among our five randomly selected ...

2015-06-10: What Happens to a Helium Balloon in Freefall?

  • 01:21: We'll be giving away t-shirts to some randomly chosen people from among those who submit correct answers with correct explanations.

2015-05-20: The Real Meaning of E=mc²

  • 01:53: That's thermal energy, or equivalently, randomized kinetic energy on a more microscopic level.

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

  • 10:30: Does quantum mechanics bring back free will since it attaches some inherent randomness to the future.

2015-03-25: Cosmic Microwave Background Explained

  • 02:12: In fact, it's called a thermal spectrum because the light is generated by the random motions of particles in the material.
  • 02:17: And those random motions are themselves a reflection of temperature.
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