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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 11:11: That causes an inward tension on the scaffold, and so it collapses.
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 17:08: ... point out that Einstein was referring to wavefunction collapse when he said "spooky action at a distance" not quantum entanglement as ... 17:23: ... was referring to general wavefunction collapse, in which the wavefunction appears to change everywhere at the instant a ... 17:37: ... discovered quantum entanglement in an effort to disprove wavefunction collapse through a reductio ad ... 17:49: He showed that instant collapse of entangle wavefunctions led to crazy FTL-like effects, and so thought it couldn’t be real. 18:04: So, “spooky action at a distance” does refer to wavefunction collapse, including to the wavefunction collapse of entangled particles.
	2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics? 03:22: They only gain specific values when  observed and the wavefunction “collapses”.
	2022-09-21: Science of the James Webb Telescope Explained! 04:03: The very first galaxies shone with intense ultraviolet light as the dense, young gas of the early universe collapsed into the first stars.
	2022-08-17: What If Dark Energy is a New Quantum Field? 13:27: ... in such a way to halt the expansion of the universe and cause it to collapse back on itself. But this flexibility makes it hard to actually falsify ...
	2022-07-20: What If We Live in a Superdeterministic Universe? 00:33: These quantum superpositions only collapse into single states when we try to measure them. 01:12: Pilot wave theory, objective collapse models, and even the Many Worlds interpretation all seek to describe a reality that exists sans observers. 02:39: We say that measurement “collapses” the wavefunction, obliterating all potential results in favor of one actual result. 07:59: Things like pilot wave theory and objective collapse models try to do that. 01:12: Pilot wave theory, objective collapse models, and even the Many Worlds interpretation all seek to describe a reality that exists sans observers. 07:59: Things like pilot wave theory and objective collapse models try to do that. 02:39: We say that measurement “collapses” the wavefunction, obliterating all potential results in favor of one actual result.
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 07:58: ... flat disks - but the TLDW is that giant   gas clouds tend to collapse into thin gas disks, and then produce stars that share that ... 03:22: ... episode on the galactic habitable zone.   The first galaxies collapsed from very slight  over-dense regions in the hot hydrogen and ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 03:40: ... energy supports the Sun against gravitational  collapse. It’s been resisting its own inward   crush for 5 billion years ... 06:56: ... together under its own gravity. Fragments broke  off to collapse into galaxies. Fragments within   those fragments collapsed ... 03:40: ... would ultimately become our Sun,   a fraction of the material collapsed  into a disk around the protostar.   Heavier elements clumped ...
	2022-05-04: Space DOES NOT Expand Everywhere 14:34: ... “observation” or “conscious awareness” as the causal event that  collapses the wavefunction,  or in this case manifests the universe. Rather ...
	2022-04-20: Does the Universe Create Itself? 01:59: ... the wavefunction, such as de Broglie-Bohm pilot wave theory or objective collapse interpretations. Still others sought to explain the observer’s influence ... 15:24: ... dictates the “temporal shape”. As in does a closed universe necessarily collapse, and an open one expand forever, and a flat one tend to zero expansion. ... 01:59: ... the wavefunction, such as de Broglie-Bohm pilot wave theory or objective collapse interpretations. Still others sought to explain the observer’s influence as a sort of ...
	2022-03-30: Could The Universe Be Inside A Black Hole? 00:58: Collapse any chunk of matter far enough and it gets stuck in its own gravity. 08:15: ... bomb fame - along with his student Hartland Snyder They approximated the collapse of a star by modeling it as a spherical cloud of matter with a perfectly ... 08:36: ... thing collapses under its own gravity and an event horizon forms around it, but within ... 10:14: There’s also the idea that universes are born as white holes produced after the collapse of a black hole. 08:36: ... thing collapses under its own gravity and an event horizon forms around it, but within ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 09:50: For one thing, unless there’s a lot of atmospheric circulation, that permanent night could cause the atmosphere to collapse, freezing to the surface. 16:39: ... we’re doing comments on the last two episodes: the one on objective collapse theories, where wavefunction collapse is explained as a real, physical ... 16:52: ... the objective collapse episode we talked about some field “hitting” the wavefunction to cause ... 09:50: For one thing, unless there’s a lot of atmospheric circulation, that permanent night could cause the atmosphere to collapse, freezing to the surface. 16:39: ... we’re doing comments on the last two episodes: the one on objective collapse theories, where wavefunction collapse is explained as a real, physical ...
	2022-02-16: Is The Wave Function The Building Block of Reality? 01:16: We say that the wave function collapses - it appears to shrink to a window whose narrow width is defined by the precision of our measurement. 01:24: ... point between atom and cat the fuzziness of the atom’s wave function collapses into one of the two states. And becomes or. Decayed and not decayed ... 02:24: ... idea of wave function collapse was first proposed by Werner Heisenberg, one of the principle founders ... 03:02: ... extremes. John von Neumann and Eugene Wigner thought that wave function collapse happens at the instant of subjective awareness - in other words, they ... 03:24: ... in Hugh Everett’s Many Worlds interpretation, the wave function never collapses, rather lasts forever, splitting into parallel realities. And we have the ... 03:59: ... wave theory. And one which avoids multiple universes by insisting that collapse does really happen. But it also avoids mystical-seeming explanations ... 04:17: ... the first in a new class of alternate quantum theories called “objective collapse ... 04:36: ... objective collapse theories, wave functions are real, physical entities that literally ... 04:54: To understand how objective collapse theories work, we need just a little more quantum mechanics. 05:44: ... wave function collapse happens, different parts of the wave function interact with each other ... 06:04: ... to model the effect of wave function collapse, Ghirardi, Rimini, and Weber added a non-linear term to the Schrodinger ... 06:22: ... the wave function takes at a particular location. That hit causes it to collapse to a particular value. And when it collapses, it immediately collapses ... 06:41: ... incredibly unlikely that a single isolated quantum particle will undergo collapse during the course of an ... 06:53: ... the more particles you add, the more likely that one of them experiences collapse, and that single single event collapses the wave function of the entire ... 07:17: ... of particles involved. Small things can stay quantum, but the chance of collapse to classicality increases with size, and big things are essentially ... 07:35: GRW suggested that the collapse rate should be about 10^-16 hits per second per particle. 07:44: ... of particles - the 6x10^23-ish of a macroscopic object, you expect a collapse every 10 nanoseconds or ... 08:02: ... Matter’s interaction with this fluctuating field would continuously collapse the wave function, in contrast to the discrete and violent hits of GRW ... 08:32: ... thought nature already gave us a perfectly good source of wave function collapse: ... 08:55: ... And 2. Why can’t gravity be quantized like the other forces. All of the collapse models attempted to answer point 1, but only Diósi and Penrose’s model ... 10:19: ... each of these objective collapse models involve modifications to the Schrödinger equation, they are not ... 10:48: ... tests of collapse models would involve putting a macroscopic object in a superposition of ... 11:09: ... have come up with clever ways to look for other, indirect signs of collapse models. For example, the models imply that a quantum wave function will ... 12:43: ... are still many candidates for objective collapse models that have not been ruled out by experiments, so stand by for a ... 16:00: ... singularity, given that time dilation slows the event down during the collapse. So this is a confusing ... 06:04: ... to model the effect of wave function collapse, Ghirardi, Rimini, and Weber added a non-linear term to the Schrodinger that could ... 08:32: ... thought nature already gave us a perfectly good source of wave function collapse: gravity. ... 08:55: ... And 2. Why can’t gravity be quantized like the other forces. All of the collapse models attempted to answer point 1, but only Diósi and Penrose’s model could ... 10:19: ... each of these objective collapse models involve modifications to the Schrödinger equation, they are not mere ... 10:48: ... tests of collapse models would involve putting a macroscopic object in a superposition of being ... 11:09: ... have come up with clever ways to look for other, indirect signs of collapse models. For example, the models imply that a quantum wave function will be ... 12:43: ... are still many candidates for objective collapse models that have not been ruled out by experiments, so stand by for a jubilant ... 08:55: ... And 2. Why can’t gravity be quantized like the other forces. All of the collapse models attempted to answer point 1, but only Diósi and Penrose’s model could answer 2: ... 10:19: ... each of these objective collapse models involve modifications to the Schrödinger equation, they are not mere ... 07:35: GRW suggested that the collapse rate should be about 10^-16 hits per second per particle. 04:17: ... the first in a new class of alternate quantum theories called “objective collapse theories. ... 04:36: ... objective collapse theories, wave functions are real, physical entities that literally collapse when ... 04:54: To understand how objective collapse theories work, we need just a little more quantum mechanics. 04:36: ... objective collapse theories, wave functions are real, physical entities that literally collapse when ... 04:54: To understand how objective collapse theories work, we need just a little more quantum mechanics. 01:16: We say that the wave function collapses - it appears to shrink to a window whose narrow width is defined by the precision of our measurement. 01:24: ... point between atom and cat the fuzziness of the atom’s wave function collapses into one of the two states. And becomes or. Decayed and not decayed ... 03:02: ... subjective awareness - in other words, they thought that consciousness collapses the wave function. At the opposite end of the spectrum, many physicists ... 03:24: ... in Hugh Everett’s Many Worlds interpretation, the wave function never collapses, rather lasts forever, splitting into parallel realities. And we have the ... 06:22: ... That hit causes it to collapse to a particular value. And when it collapses, it immediately collapses all parts of the wave function that it’s ... 06:53: ... that one of them experiences collapse, and that single single event collapses the wave function of the entire system. Any attempt to measure an ... 01:16: We say that the wave function collapses - it appears to shrink to a window whose narrow width is defined by the precision of our measurement.
	2022-01-27: How Does Gravity Escape A Black Hole? 01:01: ... to Einstein’s theory, any object that reaches such a density has to collapse to a point-like singularity of infinite density surrounded by this ...
	2022-01-19: How To Build The Universe in a Computer 07:57: ... flows into galaxies from beyond, where it rides the disk, fragments and collapses into stars, it forms  whirlpools and jets around  new stars ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 01:18: A glob of that material in the modern universe would immediately collapse into a black hole. 01:23: ... fluctuations. And so gravity had no strongly preferred direction to collapse towards. The expanding universe then thinned out this matter to more ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... interpretation of quantum mechanics we call the wave function collapse there is no real collapse not one decision is made about the location ...
	2021-11-17: Are Black Holes Actually Fuzzballs? 00:20: ... the density of matter is sufficiently ridiculous, ultimate gravitational collapse is ... 08:55: In fact, if you have a bunch of strings dense enough to form a black hole in general relativity, it wouldn’t actually collapse.
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 10:51: But dark matter doesn’t interact with light, so it would have been able to collapse just fine.
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 03:44: ... isn’t impossible, and so if you then observe the nucleus, it’ll “collapse” into one of those two states - either business as usual, or a nuclear ... 15:23: Erik says that if magnetic monopoles are massive enough to collapse the early univeres, wouldn’t we only find them inside black holes?
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 16:22: ... happens when the degeneracy pressure - the structural support against collapse produced by the Pauli exclusion principle - is ... 17:05: So the loss of electrons reduces the degeneracy pressure, allowing gravitational collapse to continue. 16:22: ... happens when the degeneracy pressure - the structural support against collapse produced by the Pauli exclusion principle - is ...
	2021-09-21: How Electron Spin Makes Matter Possible 00:26: ... stuff in our universe has structure, and that matter doesn’t immediately collapse. It’s the source of the Pauli exclusion principle, and today I’m going to ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 05:48: ... fermi gas that holds up this part of   the star from further collapse. The deeper we go, the more energetic these electrons become - ... 04:04: ... degenerate, and electron   degeneracy pressure stops further collapse and ultimately holds the atmosphere ...
	2021-09-07: First Detection of Light from Behind a Black Hole 15:39: If it’s too small and it’ll collapse on itself.
	2021-08-18: How Vacuum Decay Would Destroy The Universe 06:08: ... the bubble wall experiences a sort of surface tension that tries to collapse the bubble ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 02:29: ... there’s the Copenhagen Interpretation, which says that the wavefunction collapses at the point of measurement, leaving only one reality; or de ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 02:13: ... their remnant cores. That spin should also increase as the core slowly collapses under its own gravitational crush due to conservation of angular ... 06:21: ... pull is insane. The only thing holding the star up from absolute collapse is the fact that if it got any smaller, its electrons would start to ... 06:51: ... but they still have discrete energy levels. A forming white dwarf will collapse until the electrons are driven down to fill all of the lowest energy ... 08:29: ... happen. If a dying star’s core exceeds the Chandrasekhar limit then it collapses into a neutron star or a black hole. But If you already have a white ... 10:37: ... remnant exceeds the Chandrasekhar limit of 1.44 solar masses - absolute collapse for massive stellar cores or absolute explosion for accreting white ... 15:55: ... field - it can definitely move gas around and even trigger gas to collapse into ... 02:13: ... their remnant cores. That spin should also increase as the core slowly collapses under its own gravitational crush due to conservation of angular ... 08:29: ... happen. If a dying star’s core exceeds the Chandrasekhar limit then it collapses into a neutron star or a black hole. But If you already have a white ...
	2021-07-21: How Magnetism Shapes The Universe 10:00: Without that, those clouds would never be able to collapse all the way into stars.
	2021-07-13: Where Are The Worlds In Many Worlds? 05:22: ... - the Copenhagen Interpretation - tells us that the wavefunction “collapses” - it instantaneously shrinks from encompassing a huge range of possible ... 05:53: It says that the wavefunction never collapses - it evolves forever by the Schrodinger equation. 08:46: ... explanation for both the splitting in many worlds or the apparent collapse in ... 05:22: ... - the Copenhagen Interpretation - tells us that the wavefunction “collapses” - it instantaneously shrinks from encompassing a huge range of possible ... 05:53: It says that the wavefunction never collapses - it evolves forever by the Schrodinger equation. 05:22: ... - the Copenhagen Interpretation - tells us that the wavefunction “collapses” - it instantaneously shrinks from encompassing a huge range of possible ... 05:53: It says that the wavefunction never collapses - it evolves forever by the Schrodinger equation.
	2021-06-23: How Quantum Entanglement Creates Entropy 00:27: ... I can give you no hope;   there is nothing for it to collapse in deepest humiliation.” Eddington wasn’t the only one   ... 16:39: ... to depend on the velocity of the observer. Moving fast should then collapse the   grid in one direction - but that would reduce the ...
	2021-04-13: What If Dark Matter Is Just Black Holes? 04:48: But the most mainstream mechanism is that they collapsed from density fluctuations. 05:03: ... times and perhaps strong enough that the most massive of them would have collapsed into black ...
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 02:52: In the language of the Copenhagen interpretation of quantum mechanics, we say that the “wavefunction collapses” on observation. 03:09: ... after observation it collapses to definitely one or the other - at least, according to Copenhagen - and ... 03:47: ... you observe the arrow now, most likely it’ll “collapse” to the starting position, but there’s a small chance it would suddenly ... 04:28: Every observation you make of the arrow collapses its wavefunction into one of its possible positions - start or end. 06:53: ... to the wavefunction collapse picture, it has to make a choice - the superposition must vanish and the ... 08:43: ... do we mean by a “measurement” and what do we mean by wavefunction collapse? ... 09:55: ... idea is that measurement causes wavefunction collapse because it scrambles the delicate information connecting different parts ... 10:38: ... measure it, and that means decoherence - or the illusion of wavefunction collapse. ... 10:49: So on to wavefunction collapse. 11:18: But in this case, you’re not forcing the wavefunction to collapse back to its starting position through the power of observation. 12:15: And what is wavefunction collapse? 06:53: ... to the wavefunction collapse picture, it has to make a choice - the superposition must vanish and the electron ... 02:52: In the language of the Copenhagen interpretation of quantum mechanics, we say that the “wavefunction collapses” on observation. 03:09: ... after observation it collapses to definitely one or the other - at least, according to Copenhagen - and ... 04:28: Every observation you make of the arrow collapses its wavefunction into one of its possible positions - start or end.
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... all of the matter into neutrons they are on the edge of absolute collapse into black holes supported only by weird quantum forces neutron stars ...
	2021-01-26: Is Dark Matter Made of Particles? 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people.
	2021-01-12: What Happens During a Quantum Jump? 02:55: ... says that “measurement collapses the wavefunction”, which these days is more often taken to mean that ... 10:54: ... but in short, the act of measuring a system will, in Copenhagen terms, collapse the wavefunction, which drastically changes how the system behaves - for ... 02:55: ... says that “measurement collapses the wavefunction”, which these days is more often taken to mean that ...
	2020-12-22: Navigating with Quantum Entanglement 13:47: ... there are two main scenarios - either the core of a very massive star collapses after expending its fuel - that’s a type 2 supernova - or the remnant of ... 14:12: ... do NOT decay then quantum tunneling will cause the neutron star to collapse into a black hole over an absurdly long timescale of 10^10^20-70 or so ... 13:47: ... there are two main scenarios - either the core of a very massive star collapses after expending its fuel - that’s a type 2 supernova - or the remnant of ...
	2020-12-15: The Supernova At The End of Time 01:39: ... ball of quantum weirdness has supported itself against gravitational collapse by the pressure exerted by its electrons ... 01:52: ... one too many vanish, the entire star will undergo catastrophic collapse, and then rebound as a spectacular supernova explosion - a last firework ... 04:55: Its core would collapse until halted by electron degeneracy pressure. 06:06: ... means less electron degeneracy pressure, which means the star begins to collapse, which means more electrons driven into nuclei, and so in in a runaway ... 10:29: But that emitted positron is the antimatter counterpart of the electrons that are supporting the star from the collapse. 11:03: ... that happens, catastrophic collapse should result in a new type of supernova that will only happen in that ...
	2020-12-08: Why Do You Remember The Past But Not The Future? 13:26: Yossi Sirote asks essentially the same question - doesn't the collapse of the wave function break time symmetry. 13:33: ... IF quantum mechanics is fundamentally random, and IF the wavefunction collapse is a random rather than deterministic event, then time-reversal symmetry ... 13:47: ... personally don’t hold with random collapse interpretations, and at any rate invoking random collapse doesn’t tell ...
	2020-11-11: Can Free Will be Saved in a Deterministic Universe? 05:52: The quantum information in the state of the wave function before collapse is destroyed, but information is also created. 06:04: Information threads both end and begin at every wave function collapse.
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 02:16: ... spherical,   perfectly smooth ball of dust could  collapse into a Schwarzschild black hole,   singularity and all. Makes ... 02:48: ... It was assumed that normal, messy objects could  never collapse into a perfect point. Surely any   tiny deviation from ... 13:38: ... can look for those extra   things - the moment of wavefunction collapse, the guiding function or the empty wavefunctions of   ... 02:48: ... flying back outwards again. So, for   example, a star that collapses at the end of its life might entirely rebound as a giant ...
	2020-10-20: Is The Future Predetermined By Quantum Mechanics? 04:03: At which point, the wave function collapses into a defined state. 04:36: The dice are thrown when the wave function collapses. 04:45: Another popular interpretation of quantum mechanics is the Many-Worlds Interpretation, which simply states that the wave function never collapses. 05:13: The wave function never collapses, it evolves deterministically forever. 06:09: But now let's say we believe that other observers in the universe can also collapse the same universal wave function with their observations. 07:12: Now, there are subtleties in this wave function collapse idea. 07:16: Copenhagen doesn't specify what causes the collapse. 07:31: More physicists prefer the idea of a non-conscious interaction causing the collapse. 07:46: ... the only totally coherent way for a non-deterministic wave function collapse interpretation like Copenhagen, to give you an un-collapsed future is if ... 08:08: Your light cone sweeps through the global wave function but it doesn't collapse that wave function, rather it selects from it. 07:12: Now, there are subtleties in this wave function collapse idea. 07:46: ... the only totally coherent way for a non-deterministic wave function collapse interpretation like Copenhagen, to give you an un-collapsed future is if you are the ... 06:46: ... light cone is in their past light cone so it should have already been collapsed. ... 06:58: ... there's no way to keep the wave function of your future from being collapsed before you get ... 04:03: At which point, the wave function collapses into a defined state. 04:36: The dice are thrown when the wave function collapses. 04:45: Another popular interpretation of quantum mechanics is the Many-Worlds Interpretation, which simply states that the wave function never collapses. 05:13: The wave function never collapses, it evolves deterministically forever.
	2020-09-28: Solving Quantum Cryptography 00:10: ... new era of quantum computers may lay bare your indiscretions, as well as collapse the entire digital ... 02:29: ... better quantum computers can crack current encryption techniques and collapse the modern digital ...
	2020-09-08: The Truth About Beauty in Physics 08:04: But then a simple modification to the founding assumptions caused this mess to collapse into a supremely elegant form.
	2020-08-24: Can Future Colliders Break the Standard Model? 15:59: ... to be pounded into protons to form neutrons, causing the thing to collapse into a neutron ...
	2020-08-17: How Stars Destroy Each Other 11:27: So what happens to the neutron star after it collapses enough to form an event horizon?
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 10:08: Like I said earlier, a neutron star forms when a star’s core collapses, but most of the material rebounds as a supernova explosion. 03:34: ... the neutron stars tore themselves apart in their collision before they collapsed into a black ... 04:57: But when it ran out of fuel, gravity took over and the entire star collapsed. 10:08: Like I said earlier, a neutron star forms when a star’s core collapses, but most of the material rebounds as a supernova explosion.
	2020-05-27: Does Gravity Require Extra Dimensions? 15:33: ... the impossibly unstable inner structure of the Kerr spacetime doesn't collapse ...
	2020-05-18: Mapping the Multiverse 12:42: ... of the Kerr black hole is catastrophically unstable, and the whole thing collapses, shutting off any potential magical portals to time machines or new ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... stars before they well as they exploded as as they exploded yeah collapsed and exploded as supernovae but recent findings in particular watching ...
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 04:08: ... impossible. Fuller and Wheeler proved that the Schwarzschild wormhole collapses on itself so fast that nothing - not even light - can make it through. ... 07:52: ... matter that simply may not exist. They needed a substance to resist the collapse of the wormhole. We call such a substance exotic ... 04:08: ... impossible. Fuller and Wheeler proved that the Schwarzschild wormhole collapses on itself so fast that nothing - not even light - can make it through. ...
	2020-03-31: What’s On The Other Side Of A Black Hole? 07:10: We’ll see later how things change in the case of a black hole born of the collapse of a star.
	2020-03-24: How Black Holes Spin Space Time 11:31: ... astrophysical phenomenon - gamma ray bursts. When a truly gigantic star collapses at the end of its life, and if its core was rotating fast enough, that ... 01:44: ... went into forming it. That includes the rotation of the star’s core that collapsed into the black hole in the first place, and the rotation of any latter ... 11:31: ... astrophysical phenomenon - gamma ray bursts. When a truly gigantic star collapses at the end of its life, and if its core was rotating fast enough, that ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 05:32: ... here to talk about how entanglement is connected to measurement and the collapse of the ... 09:56: ... so our atomic measurement device doesn’t “collapse the wavefunction.” It doesn't settle measurement basis. So where does ... 08:44: ... The measurement hasn't actually happened yet. The wave function hasn't collapsed. Here’s more evidence, even with the vertically-aligned magnetic fields, ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 00:35: ... problem - the question of why and where the blurry quantum wavefunction collapses into well-defined measurement ... 00:48: We focused on a simple question: does conscious observation of a quantum system cause the wavefunction to collapse? 01:03: The upshot is that more and more physicists think that consciousness - and even measurement - don’t directly cause wavefunction collapse. 01:16: The collapse itself may be an illusion, and the alternate histories that the wavefunction represents may continue forever. 03:38: ... through two slits simultaneously as a probability wave that ultimately “collapses” to leave it as a single position on a screen, and multiple independent ... 09:18: ... effect whereby the wavefunction “knows” that it has been observed and so collapses. ... 12:31: So you shouldn’t think of yourself as this gods-eye observer, capable of seeing the whole wavefunction and causing it to collapse. 14:12: Nor is it accepted that decoherence fully explains the measurement problem and wavefunction collapse. 14:19: ... interpretation of quantum mechanics, in which there is no wavefunction collapses at ... 12:10: At this point, as far as you’re concerned, the wavefunction has collapsed - decoherence has occurred. 00:35: ... problem - the question of why and where the blurry quantum wavefunction collapses into well-defined measurement ... 03:38: ... through two slits simultaneously as a probability wave that ultimately “collapses” to leave it as a single position on a screen, and multiple independent ... 09:18: ... effect whereby the wavefunction “knows” that it has been observed and so collapses. ... 14:19: ... interpretation of quantum mechanics, in which there is no wavefunction collapses at ...
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 03:20: ... tells us that when we make that measurement the wavefunction “collapses” - it goes from a cloud of possible final destinations for the electron ... 03:34: ... collapse seems essential because our large-scale, classical world isn’t made of ... 04:46: ... wrote that wavefunction collapse must happen somewhere between the measuring apparatus and the conscious ... 05:42: With no clear boundary between the quantum and the classical, where does the collapse of the wavefunction happen? 05:53: John von Neumann believed that wavefunction collapse must happen at the moment of conscious awareness of the result of an experiment. 06:12: ... idea that consciousness collapses the wavefunction is now called the von Neumann-Wigner interpretation, ... 07:12: Only after your friend tells you the result of the experiment does their brain-wavefunction collapse to a single experimental outcome. 07:33: But there was no way for that collapse to have happened from your perspective - no information had reached you. 07:38: So there’s the conflict - different observers say the wavefunction collapses at different times. 07:55: Therefore he concluded that conscious experience must itself must play a role in generating wavefunction collapse. 09:16: ... sorts of claims - like that you can influence reality by acts of will - collapse the wavefunction in your favour to force the location of a spot on a ... 10:41: ... Heisenberg’s later writing he states that the wavefunction collapse must be a continuous process between the measurement device and the ... 11:24: You talk to each other and agree that you observed the same result - the wavefunction collapses in the same way for both of you. 11:30: So what ... maybe one of you is forcing their preferred wave function collapse on everyone else? 12:19: In fact there are some very precise explanations for why the wavefunction appears to collapse. 07:26: They think you’re crazy - they tell you the wavefunction collapsed as soon as the physical experiment was completed. 03:20: ... tells us that when we make that measurement the wavefunction “collapses” - it goes from a cloud of possible final destinations for the electron ... 06:12: ... idea that consciousness collapses the wavefunction is now called the von Neumann-Wigner interpretation, ... 07:38: So there’s the conflict - different observers say the wavefunction collapses at different times. 11:24: You talk to each other and agree that you observed the same result - the wavefunction collapses in the same way for both of you. 03:20: ... tells us that when we make that measurement the wavefunction “collapses” - it goes from a cloud of possible final destinations for the electron to ...
	2020-01-27: Hacking the Nature of Reality 12:13: ... structures in the universe today - galaxies and galaxy clusters - as collapsed from quantum fluctuations in the extremely early ...
	2020-01-20: Solving the Three Body Problem 09:25: ... equator of the sphere represents both angles being zero- that’s a fully collapsed triangle - the 3-bodies are in a straight line, as in Euler’s solutions. ...
	2020-01-13: How To Capture Black Holes 01:54: ... of the merging black holes were too massive to have been formed by the collapse of stellar cores. That is if our understanding of stellar evolution is ...
	2019-12-17: Do Black Holes Create New Universes? 03:26: ... Smolin’s mentors, Bryce deWitt, who postulated that when a black hole collapses, its mass doesn’t all end up stuck in the central, infinitely dense ... 04:14: ... possible energy environments, which is exactly the end of a black hole collapse. ... 06:13: Stars are formed when giant clouds of gas collapse under their own gravity. 09:34: The resulting material is even denser than the original neutron star, and so brings the star closer to collapse. 09:48: That in turn means less massive neutron stars would be able to collapse into black holes. 03:26: ... Smolin’s mentors, Bryce deWitt, who postulated that when a black hole collapses, its mass doesn’t all end up stuck in the central, infinitely dense ...
	2019-10-21: Is Time Travel Impossible? 05:06: They collapses on themselves instantly, leaving inescapable black holes. 08:20: His involved an entire universe, rotating about a central axis and with matter and dark energy perfectly balancing it against collapse or expansion. 05:06: They collapses on themselves instantly, leaving inescapable black holes.
	2019-08-19: What Happened Before the Big Bang? 07:19: These same fluctuations collapsed under their own gravity to become the first galaxies.
	2019-06-20: The Quasar from The Beginning of Time 05:53: Now, that gas collapsed into the very first stars, then the very first galaxies.
	2019-06-17: How Black Holes Kill Galaxies 01:35: ... We first need to understand how galaxies formed in short, Small Galaxies collapse from the gas of Big Bang then they smash together to make bigger ... 07:21: ... stars gas has to cool down before the force of gravity can cause it to collapse into the stars too hot and it stays puffed up as well as killing star ...
	2019-06-06: The Alchemy of Neutron Star Collisions 00:34: ... explosion that latter process is well understood the stars dead core collapses and protons are converted to neutrons the surrounding shells ricochet ... 02:47: ... are so high in fact that they are on the verge of complete gravitational collapse into black holes so take a pair of neutron stars in binary orbit perhaps ... 13:02: ... passed away look despite insinuations in the comments I'm sure we didn't collapse Grumpy's wavefunction - can't Has Cheezburger just by talking about it ... 00:34: ... explosion that latter process is well understood the stars dead core collapses and protons are converted to neutrons the surrounding shells ricochet ... 02:47: ... core has almost certainly pushed beyond the limits of gravity and collapses into a black hole within milliseconds in the meantime the surrounding ...
	2019-05-16: The Cosmic Dark Ages 02:52: ... years after recombination when tiny fluctuations in density began to collapse under their own gravity. These stars were exceptionally massive because ...
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... winds landed some gas exterior to the elliptical galaxy triggering it to collapse into stars even without the dark matter that would normally be needed to ...
	2019-02-20: Secrets of the Cosmic Microwave Background 02:05: ... spots on the CMB will have exactly the right size to get a single collapse or one collapse and then an expansion or two complete collapses et ... 07:42: ... ruler Spots of this size represent fluctuations that had time to collapse exactly once which means their size had to be equal to the speed of ... 02:05: ... the moment of Recombination As the universe evolved those frozen shells collapsed into galaxies We still see them today Interwoven patterns of rings drawn ...
	2019-02-07: Sound Waves from the Beginning of Time 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. 13:50: Almost certainly, there could be no quantum tunneling big crunch, but there is some smaller size that can eventually collapse that way.
	2019-01-24: The Crisis in Cosmology 07:50: ...would go on to collapse into the vast clusters of galaxies of the modern universe. 08:06: Matter wanted to collapse under its own gravity,... 08:09: ...while light generated a powerful pressure to resist that collapse.
	2019-01-09: Are Dark Matter And Dark Energy The Same? 09:43: The negative cosmological constant is the source of that slow-down and for the subsequent accelerating collapse.
	2018-10-31: Are Virtual Particles A New Layer of Reality? 10:27: ... The quantum state is not fluctuating on its own, but it will randomly collapse into one of these possibilities when something interacts with the ... 17:02: One star had collapsed into a black hole, which is why you couldn't see it.
	2018-09-12: How Much Information is in the Universe? 09:24: It gives the limit of storage capacity within a given volume before the interior collapses into a black hole.
	2018-09-05: The Black Hole Entropy Enigma 00:36: They are the inevitable result of extreme gravitational collapse. 04:49: At the instant the star collapses far enough to form an event horizon, it becomes a black hole.
	2018-08-23: How Will the Universe End? 04:15: It's so densely packed that all possible quantum states are completely filled and no further collapse is possible, short of becoming a black hole. 10:53: ... quantum tunneling should allow small regions within larger bodies to collapse into black holes, which would then consume the rest of the surrounding ... 11:14: ... that's the case, then all matter larger than a dust grain will collapse into a black hole in around 10 to the power of 10 to the power of 26 ... 04:11: This is matter that is fully collapsed in a quantum mechanical sense.
	2018-07-18: The Misunderstood Nature of Entropy 01:13: ... is nothing for it but to collapse in deepest humiliation." We've looked at entropy in the past, but it's ...
	2018-07-11: Quantum Invariance & The Origin of The Standard Model 12:46: A few of you point out that if you build a wall of lead, one likely, you'd think, to try to stop neutrinos, you would just collapse into a black hole.
	2018-06-13: What Survives Inside A Black Hole? 00:16: ... by now that black holes are weird, the result of absolute gravitational collapse of a massive body, a point of hypothetical infinite density surrounded ... 13:22: In the Copenhagen interpretation, the wave function collapses and unitarity is not preserved. 02:28: ... black hole could have formed from a collapsed star or entirely out of antimatter or photons or monkeys, but the only ... 13:22: In the Copenhagen interpretation, the wave function collapses and unitarity is not preserved.
	2018-05-23: Why Quantum Information is Never Destroyed 08:41: ... worth mentioning that the collapse of the wave function in the Copenhagen interpretation of quantum ...
	2018-04-25: Black Hole Swarms 02:16: After blowing off their outer layers, if the remaining stellar core is massive enough, it'll collapse into a black hole.
	2018-03-21: Scientists Have Detected the First Stars 02:13: Before long, some of that early hydrogen gas collapsed to form the very first stars, long before the first galaxies formed.
	2018-03-15: Hawking Radiation 00:34: ... that it allowed for the possibility of catastrophic gravitational collapse. ...
	2018-03-07: Should Space be Privatized? 11:42: When fusion switches off, the star contracts, until electron degeneracy pressure stops the collapse.
	2018-02-21: The Death of the Sun 01:31: ... from the core provides consistent support against the gravitational collapse-- well, relatively ... 02:22: ... no outward flow of energy to fight against gravity, that core begins to collapse, dragging the surrounding layer of hydrogen with ... 02:51: That burning shell is so thin that radiation escapes outwards without providing pressure to resist collapse. 02:58: Instead, the helium produced in the shell is deposited on the dead core, causing the inner regions to collapse further. 03:52: While the stars outer layers of hydrogen are expanding and cooling, the core continues to collapse until it hits a quantum mechanical limit. 02:22: ... no outward flow of energy to fight against gravity, that core begins to collapse, dragging the surrounding layer of hydrogen with ... 07:11: The naked core of 100,000 Kelvin degenerate carbon and oxygen has collapsed to the size of the Earth.
	2018-01-24: The End of the Habitable Zone 01:28: ... when the sun was born, it's initial gravitational collapse from a giant gas cloud was halted as soon as the core became dense ... 02:02: The core collapses slightly under the immense weight above it.
	2017-12-20: Extinction by Gamma-Ray Burst 02:34: As many of you know, a supernova is the explosion that follows the catastrophic collapse of a massive star at the end of its life.
	2017-10-25: The Missing Mass Mystery 04:00: These speckles are fluctuations in density that would later collapse to become the galaxy clusters. 05:08: ... of the cosmic background radiation, gravity continued to do its work and collapse these faint fluctuations into gargantuan clusters of ... 05:20: Supercomputer simulations reveal the shape of this large-scale structure that should result from this gravitational collapse.
	2017-09-20: The Future of Space Telescopes 12:26: As this happens, the stellar core succumbs to the gravitational crush and collapses incredibly quickly. 12:33: During that collapse, the core looks more and more like a neutron star, basically a giant ball of neutrons with the density of an atomic nucleus. 12:42: ... a neutron star holds this collapse, when they hit neutron degeneracy pressure, the most massive stars don't ... 13:05: ... into quarks-- and then who knows what-- as the core continues to collapse towards the ... 12:26: As this happens, the stellar core succumbs to the gravitational crush and collapses incredibly quickly.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 02:00: For the most massive stars, that core will collapse into a black hole.
	2017-08-30: White Holes 03:49: Now, a real black hole forms from the gravitational collapse of a massive star's core. 03:55: ... the collapse, the future singularity comes into being, and in the past, well, there's ...
	2017-08-16: Extraterrestrial Superstorms 04:09: They are most often anti-cyclonic, high-pressure systems and are powered not by the sun, but by the collapse of the planet itself. 04:28: But five billion years later, that collapse continues, albeit very slowly. 04:23: They originally collapsed from the vast gas disk left over after the sun's birth.
	2017-06-21: Anti-Matter and Quantum Relativity 05:10: ... a single simple idea that caused the resulting horrendous mathematics to collapse into an incredibly simple, beautiful ...
	2017-05-31: The Fate of the First Stars 05:52: Stars form when vast clouds of mostly molecular hydrogen collapse under their own gravity. 05:58: Now, for that collapse to proceed, the pull of gravity needs to overcome the cloud's own internal thermal pressure. 06:12: To collapse into stars, clouds have to cool. 06:58: Unimpeded by pesky thermal pressure, the cloud collapses quickly. 07:03: In fact, any over-dense lump within the cloud will, itself, collapse, causing the cloud to fragment. 07:31: Thermal pressure kicks in much earlier to slow the collapse, before much of the fragmentation happens. 08:57: In fact, it may be that stars greater than around 250 solar masses can collapse directly into a black hole without exploding. 07:03: In fact, any over-dense lump within the cloud will, itself, collapse, causing the cloud to fragment. 08:57: In fact, it may be that stars greater than around 250 solar masses can collapse directly into a black hole without exploding. 06:58: Unimpeded by pesky thermal pressure, the cloud collapses quickly.
	2017-04-26: Are You a Boltzmann Brain? 07:12: For example, why collapse a whole universe worth of particles? 07:17: Such systems should massively outnumber larger, big-bang collapses.
	2017-03-01: The Treasures of Trappist-1 10:48: ... region of cloud can be before it fragments, because local gravitational collapse happens faster than pressure can equalize across the ...
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 02:26: As the gas collapses, it builds up heat and density until the pressure of the gas dramatically slows collapse. 02:38: The protostar continues to collapse more slowly until eventually the core gets hot and dense enough to ignite in fusion. 02:47: And outflowing energy resists any further collapse. 08:34: Stars typically form in groups as very large clouds of molecular hydrogen collapse and break apart into separate pieces. 02:26: As the gas collapses, it builds up heat and density until the pressure of the gas dramatically slows collapse.
	2017-02-02: The Geometry of Causality 14:13: ... of the accretion disks sometimes become gravitationally unstable and collapse, in which case you might get some weird stardust-like activity and some ...
	2017-01-25: Why Quasars are so Awesome 08:46: Hot gas doesn't collapse into stars, and so the extreme starburst activity was shut down.
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 06:27: The surface of our star is represented by its starting radius at t equals zero, but as time moves forward, the radius shrinks as the star collapses. 09:48: But it's not quite a black hole, and so in principle, the sphere doesn't have to collapse. 06:27: The surface of our star is represented by its starting radius at t equals zero, but as time moves forward, the radius shrinks as the star collapses.
	2016-12-14: Escape The Kugelblitz Challenge 01:35: A black hole forms when the core of a very massive star collapses under its own gravity at the end of a star's life. 01:52: When the core of this star has fused all of its elements into iron, it will start to collapse under its own weight. 01:58: There is a specific size that represents the point of no return for this collapse. 02:11: If the star's core collapses to a size smaller than its own Schwarchild radius, then the event horizon forms, engulfing what's left of the star. 01:35: A black hole forms when the core of a very massive star collapses under its own gravity at the end of a star's life. 02:11: If the star's core collapses to a size smaller than its own Schwarchild radius, then the event horizon forms, engulfing what's left of the star.
	2016-11-16: Strange Stars 00:55: Einstein's general theory of relativity tells us that the core of a dead star must collapse under its own incredible weight. 01:08: ... already talked about how quantum processes save a neutron star from collapse, but ultimately also doom the most massive to collapse into a black ... 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies. 01:52: In that collapse, most of the electrons and protons are crunched together to form neutrons. 07:08: And those may provide the final pressure that halts the collapse of some stars into a black hole, at least for another million years or so. 08:59: And it's been hypothesized that these may be due to a second explosion as the neutron star collapses further into a quark star.
	2016-10-26: The Many Worlds of the Quantum Multiverse 02:04: ... of quantum mechanics, the act of measurement was thought to collapse possibility space into a single reality, at least with respect to the ... 02:16: It collapses the wave function. 02:19: That collapse signifies the transition between the quantum and classical realms. 03:17: But why can't the cat collapse its own wave function? 05:12: What if the wave function never collapses? 08:18: ... quantum mechanics because there's nothing in that math that requires the collapse of the wave ... 02:04: ... of quantum mechanics, the act of measurement was thought to collapse possibility space into a single reality, at least with respect to the measured ... 02:19: That collapse signifies the transition between the quantum and classical realms. 07:57: It's just that Copenhagen merges them into a single timeline with its wave function collapsed. 02:16: It collapses the wave function. 05:12: What if the wave function never collapses?
	2016-10-19: The First Humans on Mars 09:52: A star's core needs to be more massive than around three times the mass of the sun in order to collapse into a black hole.
	2016-10-12: Black Holes from the Dawn of Time 02:19: These density fluctuations were enough to kick-start the formation of galaxies, but certainly not enough to immediately collapse into black holes. 03:21: For example, the collapse of cosmic string moves and the collision of bubble universes?
	2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate 03:49: ... Copenhagen interpretation, any measurement of one particle automatically collapses the entire entangled wave function, and so affects the results of ... 06:43: In that case, measurement of one particle spin should cause the entire wave function to collapse, to take on defined values. 03:49: ... Copenhagen interpretation, any measurement of one particle automatically collapses the entire entangled wave function, and so affects the results of ...
	2016-08-10: How the Quantum Eraser Rewrites the Past 01:19: It's a probability wave that does all the usual wave-like stuff like making interference patterns, until something happens to collapse it. 07:29: ... down on the interpretation that observation of the path causes the collapse of the wave function, and that the wave function can collapse all the ... 08:01: ... slit screen, somehow the entire wave function knows to do this-- to collapse at the same ...
	2016-08-03: Can We Survive the Destruction of the Earth? ft. Neal Stephenson 08:58: ... a very massive star goes supernova, the resulting collapse of the core into a neutron star, or black hole, can produce these ... 11:15: ... than a distribution of probabilities, and that when the wave function collapses, the properties of the resulting particle are picked randomly from that ...
	2016-07-27: The Quantum Experiment that Broke Reality 08:27: ... transition from a possibility space to a defined set of properties "the collapse of the wave function." It tells us that prior to the collapse, it's ... 11:45: Well, the Sun and other stars don't need rocky cores because they are massive enough for all of that gas to collapse by itself.
	2016-06-15: The Strange Universe of Gravitational Lensing 04:09: ... parameter space is a configuration of lens and light source that will collapse those distorted images into the true galaxies that created ... 11:07: So some of the language I used to describe the collapse of the wave function and possible positions did echo the Copenhagen interpretation. 12:02: ... and others, allow a deterministic interpretation of the so-called collapse of the wave ... 12:39: ... a quantum system means doing something to it that collapses its wave function into the classical physical properties like position ... 13:09: However, one view that's not really favored is the idea that a conscious observer is needed to collapse a wave function. 12:39: ... a quantum system means doing something to it that collapses its wave function into the classical physical properties like position ...
	2016-06-01: Is Quantum Tunneling Faster than Light? 01:04: The reduction of a fuzzy possibility space into a specific measurable property is sometimes referred to as the collapse of the wave function. 02:16: Observe me and you'll collapse my wave function and probably find me pretty much exactly where you expect to.
	2016-05-18: Anti-gravity and the True Nature of Dark Energy 03:48: The more matter and energy in the universe, the harder gravity pulls inwards, trying to stop the expansion or speed up the collapse.
	2016-04-13: Will the Universe Expand Forever? 06:09: ... the kinetic energy of expansion and the potential energy of collapse are perfectly balanced, then the universe will expand to a ginormous ... 07:07: Will the universe expand forever, or collapse? 12:21: It collapsed into the Sun's sibling stars, which are also scattered across the galaxy by now.
	2016-04-06: We Are Star Stuff 07:05: So that iron core, once formed, can do nothing to prevent its own gravitational collapse. 07:11: And collapse it does, taking about a tenth of a second to collapse from around the size of planet Earth to the size of a city. 07:24: ... the surrounding onion shells of lighter elements collapse also, but they hit the brick wall of the newly born neutron star and ...
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 04:24: So each tower is responsible for only supporting itself from downward collapse. 08:36: It's because the effect that prevents their collapse has a very different symmetry. 08:42: Let's think about what happens when a vast interstellar cloud of gas and dust collapses to form a star. 08:49: These things are so huge and spread out, they barely fuel their own gravity, and they collapse very, very slowly. 08:56: They also start out spinning very slowly, but that spin speeds up as they collapse, just like a spinning ice skater. 09:10: This global rotation makes it even harder for the cloud to collapse. 09:28: The cloud can still collapse in the down direction, and it does so, ending up as a spinning disk when it finds itself in equilibrium. 11:12: Felix Ironfist asks, "why didn't the universe collapse into a black hole, if it was so dense and massive?" This is a classic question. 08:42: Let's think about what happens when a vast interstellar cloud of gas and dust collapses to form a star.
	2016-03-09: Cosmic Microwave Background Challenge 01:00: We're looking at an ocean of orangey, red-hot plasma that would later collapse into galaxies, and people, and stuff.
	2016-02-24: Why the Big Bang Definitely Happened 05:16: Very, very tiny fluctuations that would let it collapse on themselves to form galaxies and clusters of galaxies. 05:36: When we look to vast distances, we're also looking back in time and we see the very first galaxies soon after they collapsed from these blobs.
	2016-02-11: LIGO's First Detection of Gravitational Waves! 02:12: In both cases, these are the collapsed core of a dead star, stellar remnants.
	2015-12-09: How to Build a Black Hole 01:58: So starved of an energy source, the stellar core collapses on itself. 02:39: And it's a quantum phenomenon that saves it, for the moment, from final collapse. 03:29: These govern the delicate balance between stability and collapse. 04:32: ... pressure, resulting from particles not having anywhere else to collapse into, is incredibly strong-- strong enough to initially resist the ... 09:00: But there's no stopping ultimate collapse. 09:13: All position space collapses towards the singularity. 10:20: And very few other properties of the collapsed material are remembered. 01:58: So starved of an energy source, the stellar core collapses on itself. 09:13: All position space collapses towards the singularity.
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 12:04: ... you collapse the way function of one entangled particle, your choice of measurement ...
	2015-09-30: What Happens At The Edge Of The Universe? 08:42: To collapse completely into a star-sized object, it would have to lose a lot more energy. 08:57: But then these clouds radiate light in different ways, allowing the gas to cool even more and collapse into stars. 08:42: To collapse completely into a star-sized object, it would have to lose a lot more energy.
	2015-08-19: Do Events Inside Black Holes Happen? 09:13: ... are infinitely dense because all the stuff that goes into the black hole collapses to an infinitely dense point called the singularity at the center, ... 09:33: ... form when a sufficiently massive object, typically a very heavy star, collapses and becomes more compact than its own Schwarzschild ... 09:13: ... are infinitely dense because all the stuff that goes into the black hole collapses to an infinitely dense point called the singularity at the center, ... 09:33: ... form when a sufficiently massive object, typically a very heavy star, collapses and becomes more compact than its own Schwarzschild ...
	2015-04-08: Could You Fart Your Way to the Moon? 06:43: ... all asked in one way or another why the shell of the moon wouldn't collapse and get sucked into the black ...

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