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	2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics? 01:24: You have two balls - one black, one white. 01:38: While that box is closed, the ball on the moon has a 50-50 chance of being black or white. 02:13: Each ball is in a superposition state of maybe black-maybe white until a measurement is made.
	2022-09-21: Science of the James Webb Telescope Explained! 09:28: Those white blobby things are massive elliptical galaxies of the cluster, several billion light years away.
	2022-08-24: What Makes The Strong Force Strong? 10:03: Your screen can’t make this color, or this one, or even this pure white. 10:12: White is what you get when you combine the three in equal quantities - that’s your red + green + blue = 0. 13:22: ... or as we know them better, cyan, yellow and magenta, and then black and white at the ... 13:56: ... of three, and two of those combinations are neutral, like black and white for example, you get this mathematical ...
	2022-04-20: Does the Universe Create Itself? 17:08: ... physics. In a way that’s right. If the universe is a black or a white hole then it formed by a different process than the black holes that ...
	2022-03-30: Could The Universe Be Inside A Black Hole? 06:05: It’s a white hole, and it’s a valid a solution to the Einstein equations. 06:13: ... past, space-like singularity of the white hole is surrounded by an event horizon that is the opposite to a black ... 06:35: But there’s still an “outside” in which the white hole appears as a bright, localized point in space. 06:48: On the other hand, anyone inside the white hole wouldn't know that. 06:59: At first glance, despite the similarities the interior of the white hole looks nothing like our universe. 07:06: Now the white hole was “discovered” by messing around with the coordinates of the OG black hole solution by Karl Schwarzschild. 07:22: The interior of this type of white hole looks nothing like our universe. 07:48: And the space-time curvature is nearly flat, so no crazy tidal forces like in a white or black hole. 08:05: But there is actually a way to fit an FLRW metric inside a black or white hole so that those inside it couldn’t tell the difference. 09:43: If it works for the black hole then it should work for the white hole. 09:47: Just flip the timel axis and you have a white hole containing a bubble of expanding space that looks much like our universe. 09:55: If such a white hole was big enough, it could look exactly like our universe. 10:14: There’s also the idea that universes are born as white holes produced after the collapse of a black hole. 10:27: ... rather bounce back outward to create a new spacetimes from the resulting white hole - which itself creates new black holes, ... 10:48: ... from the cosmic microwave background - then the line between the white hole and black hole becomes ... 11:08: ... you lump all of this together - a very specific construction for white holes to make them look like our universe from within, and Hawking’s ... 11:27: Or a white hole? 06:05: It’s a white hole, and it’s a valid a solution to the Einstein equations. 06:13: ... past, space-like singularity of the white hole is surrounded by an event horizon that is the opposite to a black hole ... 06:35: But there’s still an “outside” in which the white hole appears as a bright, localized point in space. 06:48: On the other hand, anyone inside the white hole wouldn't know that. 06:59: At first glance, despite the similarities the interior of the white hole looks nothing like our universe. 07:06: Now the white hole was “discovered” by messing around with the coordinates of the OG black hole solution by Karl Schwarzschild. 07:22: The interior of this type of white hole looks nothing like our universe. 08:05: But there is actually a way to fit an FLRW metric inside a black or white hole so that those inside it couldn’t tell the difference. 09:43: If it works for the black hole then it should work for the white hole. 09:47: Just flip the timel axis and you have a white hole containing a bubble of expanding space that looks much like our universe. 09:55: If such a white hole was big enough, it could look exactly like our universe. 10:27: ... rather bounce back outward to create a new spacetimes from the resulting white hole - which itself creates new black holes, ... 10:48: ... from the cosmic microwave background - then the line between the white hole and black hole becomes ... 11:27: Or a white hole? 10:27: ... rather bounce back outward to create a new spacetimes from the resulting white hole - which itself creates new black holes, ... 06:35: But there’s still an “outside” in which the white hole appears as a bright, localized point in space. 10:14: There’s also the idea that universes are born as white holes produced after the collapse of a black hole. 11:08: ... you lump all of this together - a very specific construction for white holes to make them look like our universe from within, and Hawking’s argument ... 10:14: There’s also the idea that universes are born as white holes produced after the collapse of a black hole.
	2022-03-23: Where Is The Center of The Universe? 10:53: We might ask whether the Big Bang is a reverse black hole - also called a white hole.
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 14:45: Four lights are visible through the thick atmosphere - the gleaming white twins Tolimar and Rigel Kentaurus, the glowering red orb of Proxima herself. 14:56: But there’s another white star on the horizon,  but it’s slowly slipping away on its own orbit around the Milky Way. 14:45: Four lights are visible through the thick atmosphere - the gleaming white twins Tolimar and Rigel Kentaurus, the glowering red orb of Proxima herself.
	2021-12-10: 2021 End of Year AMA! 00:02: ... this is actually normally a luxurious brown i paint on these little white parts just to gain some amount of credibility in academia these are ...
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 16:32: ... massive enough it smashes through the degeneracy pressure that supports white dwarf stars and instead produces a black hole or neutron ...
	2021-09-21: How Electron Spin Makes Matter Possible 16:27: ... were just discovered and there was speculation that they might be white holes. So I came along only a little after, I imagine those were giddy ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 04:04: ... is   not all that different from the stuff inside  of a white dwarf - the dead core of a lower   mass star like our Sun. The ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 14:02: ... episode we talked about this one very weird white dwarf star that scientists think may be the first observation of the ... 14:53: ... by awuma to help answer this. Awuma tells us that such rapidly rotating white dwarfs are found in post-common envelope close binary systems - V471 ... 15:35: ... this tells me that yes, you can greatly spin up a white dwarf by feeding it the envelope of its binary partner. But is there a ... 15:46: ... goes on to explode as a supernova. But the mass transfer onto the white dwarf actually makes this less likely because losing mass reduces the ... 14:02: ... episode we talked about this one very weird white dwarf star that scientists think may be the first observation of the result of ... 14:53: ... that they share an envelope - you can also describe that as saying he white dwarf orbits inside the other star. Now V471 is a post-common-envelope system, ... 15:35: ... this tells me that yes, you can greatly spin up a white dwarf by feeding it the envelope of its binary partner. But is there a way to ... 15:46: ... goes on to explode as a supernova. But the mass transfer onto the white dwarf actually makes this less likely because losing mass reduces the internal ... 14:02: ... from being the result of a merger, rather than being a more usual white dwarf accreting from a partner star before being ejected from that binary system. OK, so ... 15:46: ... - but it seems these scientists think that, that's less likely that the white dwarf collision explanation, which at any rate we know must happen at least ... 14:53: ... that they share an envelope - you can also describe that as saying he white dwarf orbits inside the other star. Now V471 is a post-common-envelope system, ... 14:02: ... episode we talked about this one very weird white dwarf star that scientists think may be the first observation of the result of the ... 14:53: ... by awuma to help answer this. Awuma tells us that such rapidly rotating white dwarfs are found in post-common envelope close binary systems - V471 Tauri with ... 14:02: ... think may be the first observation of the result of the merger of two white dwarfs - and how this may have huge implications for all of cosmology. Let’s see ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 00:21: ... particular “huh, that’s weird” takes the form of a white dwarf star that’s doing some stuff that no white dwarf should ever be ... 00:47: ... objects that vary over time. Astronomers using the ZTF caught a white dwarf that, at first glance, looked suspicious - a bit too massive and ... 01:31: ... Observations with the Hale Telescope confirmed that it’s 1) definitely a white dwarf, and 2) definitely spinning way too fast to make ... 01:45: ... we get into why this is so weird, let’s review what we know about white dwarfs - or at least, what we thought we knew. When all but the most ... 02:13: ... how we thought all white dwarfs were formed. But something is off with Zee - particularly with ... 02:51: ... in the world. Keck was needed to do the spectroscopy - to break the white dwarf’s light up into component colours. Splitting the light this way ... 03:19: ... or sun’s magnetic field. That’s at the top tier of the most magnetic white ... 05:39: ... 2140 kilometers, plus or minus a few hundred. And that is tiny, even by white dwarf ... 05:51: ... comparison, a white dwarf the mass of our sun would be around the size of the earth, this ... 06:04: ... one reason that it’s good to know the size of a white dwarf is that it also tells you its mass. Here we need to learn ... 06:17: That’s true of planets and regular stars, but it’s not true of white dwarfs. 06:21: ... white dwarfs, matter is crushed so close together that the inward ... 06:51: ... closer the electron is to escaping the atom. Electrons are bound to the white dwarf by gravity, but they still have discrete energy levels. A forming ... 07:24: ... happens if you add more mass to a white dwarf? First let’s think about what happens when you add mass to less ... 08:05: ... if Zee is the smallest known white dwarf it must also be the most massive. Doing a little quantum ... 08:29: ... collapses into a neutron star or a black hole. But If you already have a white dwarf and then slowly add more mass it’ll explode as a type 1a ... 08:48: ... fate very soon. OK, let’s review the evidence. We have one weird white dwarf - it’s extremely massive and compact - but that’s not so strange ... 09:18: ... never seen conclusive evidence for it. Zee could be the result of a white dwarf collision. If two white dwarfs are orbiting each other, we expect ... 09:51: ... a pair of white dwarfs merge, two things might happen - either their mass adds up to ... 10:37: ... so we have a possible origin story for this white dwarf. Remember I said that we should assume typical until proven weird? ... 11:20: ... don’t actually know - it could go either way. But if merging white dwarfs DO explode then it may well be that many of the type 1a ... 11:52: ... out that a significant number of those supernovae came from merging white dwarfs rather than accreting white dwarfs then perhaps our calculations ... 12:16: ... to a black dwarf over trillions of years? That’s the usual doom of a white dwarf. But Zee may get its explosive finale after all. A typical white ... 12:50: ... a chain reaction of so-called electron capture which is how you turn a white dwarf into a neutron ... 13:41: ... we have it- ZTF J1901+1458 - Zee - is a moon-sized, highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each ... 14:14: ... of space around us thrums with the infinitesimal vibrations of countless white dwarfs that have merged since the beginning of time. With the help of ... 14:52: ... turns out that they sing your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons ... 00:21: ... particular “huh, that’s weird” takes the form of a white dwarf star that’s doing some stuff that no white dwarf should ever be able to ... 00:47: ... objects that vary over time. Astronomers using the ZTF caught a white dwarf that, at first glance, looked suspicious - a bit too massive and ... 01:31: ... Observations with the Hale Telescope confirmed that it’s 1) definitely a white dwarf, and 2) definitely spinning way too fast to make ... 02:13: ... it’s hard to see how any star could be rotating fast enough to produce a white dwarf that spins every 7 ... 05:39: ... 2140 kilometers, plus or minus a few hundred. And that is tiny, even by white dwarf ... 05:51: ... comparison, a white dwarf the mass of our sun would be around the size of the earth, this new guy ... 06:04: ... one reason that it’s good to know the size of a white dwarf is that it also tells you its mass. Here we need to learn something ... 06:51: ... closer the electron is to escaping the atom. Electrons are bound to the white dwarf by gravity, but they still have discrete energy levels. A forming white ... 07:24: ... happens if you add more mass to a white dwarf? First let’s think about what happens when you add mass to less weird ... 08:05: ... if Zee is the smallest known white dwarf it must also be the most massive. Doing a little quantum mechanics, it ... 08:29: ... collapses into a neutron star or a black hole. But If you already have a white dwarf and then slowly add more mass it’ll explode as a type 1a ... 08:48: ... fate very soon. OK, let’s review the evidence. We have one weird white dwarf - it’s extremely massive and compact - but that’s not so strange in ... 09:18: ... never seen conclusive evidence for it. Zee could be the result of a white dwarf collision. If two white dwarfs are orbiting each other, we expect them ... 09:51: ... come back to. Or it adds up to less and we get a bigger, much weirder white dwarf. That star would be spinning really really fast because it doesn’t just ... 10:37: ... so we have a possible origin story for this white dwarf. Remember I said that we should assume typical until proven weird? Well ... 12:16: ... to a black dwarf over trillions of years? That’s the usual doom of a white dwarf. But Zee may get its explosive finale after all. A typical white dwarf is ... 12:50: ... a chain reaction of so-called electron capture which is how you turn a white dwarf into a neutron ... 13:41: ... we have it- ZTF J1901+1458 - Zee - is a moon-sized, highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each ... 14:52: ... turns out that they sing your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons be ... 08:48: ... fate very soon. OK, let’s review the evidence. We have one weird white dwarf - it’s extremely massive and compact - but that’s not so strange in ... 14:52: ... turns out that they sing your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons be ever ... 09:18: ... never seen conclusive evidence for it. Zee could be the result of a white dwarf collision. If two white dwarfs are orbiting each other, we expect them to slowly ... 10:37: ... assume typical until proven weird? Well that still applies. If this one white dwarf formed this way, that means others probably did also. And it means that white ... 05:39: ... 2140 kilometers, plus or minus a few hundred. And that is tiny, even by white dwarf standards. ... 00:21: ... particular “huh, that’s weird” takes the form of a white dwarf star that’s doing some stuff that no white dwarf should ever be able to do. ... 08:05: ... weigh in at 1.32 times the Sun’s mass. And that’s a lot, at least for a white dwarf. We’ve known for some time that the absolute maximum mass for a white dwarf is ... 00:21: ... that it almost certainly did NOT form in the way that we thought all white dwarfs formed. This one peculiar point of faint light may change our ... 01:45: ... we get into why this is so weird, let’s review what we know about white dwarfs - or at least, what we thought we knew. When all but the most massive ... 02:13: ... how we thought all white dwarfs were formed. But something is off with Zee - particularly with how fast ... 02:51: ... in the world. Keck was needed to do the spectroscopy - to break the white dwarf’s light up into component colours. Splitting the light this way makes it ... 03:19: ... or sun’s magnetic field. That’s at the top tier of the most magnetic white dwarfs. ... 06:04: ... you its mass. Here we need to learn something that’s weird about all white dwarfs, not just Zee. We normally think about objects getting bigger the more ... 06:17: That’s true of planets and regular stars, but it’s not true of white dwarfs. 06:21: ... white dwarfs, matter is crushed so close together that the inward gravitational pull ... 07:24: ... that adding matter usually causes an object to increase in size. But for white dwarfs it’s different - as you add mass, the white dwarf has to actually shrink ... 08:48: ... strong magnetic field. We just don’t see these extreme properties in the white dwarfs produced as stars ... 09:18: ... for it. Zee could be the result of a white dwarf collision. If two white dwarfs are orbiting each other, we expect them to slowly spiral together ... 09:51: ... a pair of white dwarfs merge, two things might happen - either their mass adds up to more than ... 10:37: ... collapse for massive stellar cores or absolute explosion for accreting white dwarfs. So what happens to merging white dwarfs that exceed this ... 11:20: ... don’t actually know - it could go either way. But if merging white dwarfs DO explode then it may well be that many of the type 1a supernovae that ... 11:52: ... out that a significant number of those supernovae came from merging white dwarfs rather than accreting white dwarfs then perhaps our calculations of the ... 13:41: ... highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each other. It teeters on the edge of explosion, and may ... 14:14: ... of space around us thrums with the infinitesimal vibrations of countless white dwarfs that have merged since the beginning of time. With the help of your ... 01:45: ... we get into why this is so weird, let’s review what we know about white dwarfs - or at least, what we thought we knew. When all but the most massive ... 00:21: ... that it almost certainly did NOT form in the way that we thought all white dwarfs formed. This one peculiar point of faint light may change our understanding of ... 02:51: ... in the world. Keck was needed to do the spectroscopy - to break the white dwarf’s light up into component colours. Splitting the light this way makes it even ... 06:21: ... white dwarfs, matter is crushed so close together that the inward gravitational pull is ... 09:51: ... a pair of white dwarfs merge, two things might happen - either their mass adds up to more than the ... 08:48: ... strong magnetic field. We just don’t see these extreme properties in the white dwarfs produced as stars ... 13:41: ... highly magnetized white dwarf probably formed when two low mass white dwarfs spiralled into each other. It teeters on the edge of explosion, and may force us ...
	2021-04-13: What If Dark Matter Is Just Black Holes? 06:48: For example, they’d puncture white dwarfs and neutron stars on a regular basis. 06:53: ... primordial micro-black hole would pass right through a white dwarf, but it would deposit enough heat to allow the stars' ultra dense ... 06:48: For example, they’d puncture white dwarfs and neutron stars on a regular basis.
	2021-03-16: The NEW Crisis in Cosmology 03:13: ... - the incredibly bright “type 1a” supernovae that result when a white dwarf   star explodes after cannibalizing its binary  ...
	2020-12-22: Navigating with Quantum Entanglement 13:47: ... - that’s a type 2 supernova - or the remnant of a lower mass star - a white dwarf - gains extra mass and explodes - that’s a type ... 14:50: The Star may go through a phase as a white - or perhaps now black dwarf and will continue to evaporate due to proton decay. 13:47: ... - that’s a type 2 supernova - or the remnant of a lower mass star - a white dwarf - gains extra mass and explodes - that’s a type ... 03:31: This “geomagnetic” field is generated by the convective motion in Earth’s outer core - which is a churning liquid mass of white-hot nickel and iron.
	2020-12-15: The Supernova At The End of Time 04:18: A new type of star had been discovered - white dwarfs. 04:58: Meanwhile the outer layers would have been ejected, leaving its exposed core as the white dwarf. 05:05: Most eminent physicists of the era were coming to believe that the white dwarf should be the fate of all stars. 05:37: And in the extreme density of a white dwarf, electrons would indeed be traveling fast enough for relativity to change the physics. 06:24: ... on the SS Pilsner, Chandra just knew that no white dwarf could exist above that mass limit - what we now call the ... 07:16: In a white dwarf, the nuclei can never recapture their electrons to become atoms again. 07:35: ... all white dwarfs must cool to the temperature of the ambient space - now a frigid ... 07:49: Eventually, all white dwarf must fade to near-invisible nuggets we call black dwarfs. 09:02: ... protons can decay, then the entire white dwarf will vaporize into a subatomic mist in a mere 10^32 or so years, ... 10:50: ... means that a white dwarf - or now iron black dwarf - that was initially stable with a mass ... 04:58: Meanwhile the outer layers would have been ejected, leaving its exposed core as the white dwarf. 05:05: Most eminent physicists of the era were coming to believe that the white dwarf should be the fate of all stars. 05:37: And in the extreme density of a white dwarf, electrons would indeed be traveling fast enough for relativity to change the physics. 06:24: ... on the SS Pilsner, Chandra just knew that no white dwarf could exist above that mass limit - what we now call the Chandrasekhar ... 07:16: In a white dwarf, the nuclei can never recapture their electrons to become atoms again. 07:49: Eventually, all white dwarf must fade to near-invisible nuggets we call black dwarfs. 09:02: ... protons can decay, then the entire white dwarf will vaporize into a subatomic mist in a mere 10^32 or so years, long ... 10:50: ... means that a white dwarf - or now iron black dwarf - that was initially stable with a mass below ... 05:37: And in the extreme density of a white dwarf, electrons would indeed be traveling fast enough for relativity to change the physics. 04:18: A new type of star had been discovered - white dwarfs. 07:35: ... all white dwarfs must cool to the temperature of the ambient space - now a frigid 3 ...
	2020-08-24: Can Future Colliders Break the Standard Model? 15:59: ... limit is 1.4 times the mass of the sun - it’s the maximum mass of a white dwarf before crushing gravitational pressure causes electrons to be ... 16:19: But what about white dwarfs that gain more mass after they form? Or that collide to have above that mass? 16:36: ... the white dwarf exceeds the limit by cannibalizing a companion star, and also ... 16:46: Instead you’re most likely to just get an explosion as thermonuclear fusion rips through the white dwarfs carbon and oxygen interior. 15:59: ... limit is 1.4 times the mass of the sun - it’s the maximum mass of a white dwarf before crushing gravitational pressure causes electrons to be pounded ... 16:36: ... the white dwarf exceeds the limit by cannibalizing a companion star, and also presumably ... 16:19: But what about white dwarfs that gain more mass after they form? Or that collide to have above that mass? 16:46: Instead you’re most likely to just get an explosion as thermonuclear fusion rips through the white dwarfs carbon and oxygen interior.
	2020-08-17: How Stars Destroy Each Other 00:44: Ejecting its outer layers, it became a searing hot, planet-sized orb of incredible density - a white dwarf. 01:11: There, in the extreme surface gravity of the ultradense white dwarf, a layer of hydrogen built up. 01:22: ... storm of fusion ripped around the planet-sized white dwarf, spraying its atmosphere into space and for a couple of weeks ... 02:16: ... we’re going to look at the worst of these - from the novae produced by white dwarfs, to X-ray binaries created by neutron stars and black holes - and ... 03:07: ... finally identified a nearby flaring white dwarf binary - a so-called cataclysmic variable - and realized that it ... 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova. 04:31: If the white dwarf has a strong magnetic field, the flow of gas from its companion is channeled by that field. 04:38: ... bright X-ray light is emitted as the gas hits the polar regions of the white dwarf - like a particularly violent ... 04:59: Just replace the white dwarf with a neutron star or black hole. 09:38: The white dwarf in these systems builds up mass until releasing it as a nova. 09:47: The rest stays with the white dwarf, which slowly grows in mass. 09:51: Eventually, the core of the white dwarf reaches a temperature of hundred of millions of Kelvin, and the star’s carbon and oxygen can begin to fuse. 00:44: Ejecting its outer layers, it became a searing hot, planet-sized orb of incredible density - a white dwarf. 01:11: There, in the extreme surface gravity of the ultradense white dwarf, a layer of hydrogen built up. 01:22: ... storm of fusion ripped around the planet-sized white dwarf, spraying its atmosphere into space and for a couple of weeks shining 10s ... 03:07: ... finally identified a nearby flaring white dwarf binary - a so-called cataclysmic variable - and realized that it was the ... 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova. 04:31: If the white dwarf has a strong magnetic field, the flow of gas from its companion is channeled by that field. 04:38: ... bright X-ray light is emitted as the gas hits the polar regions of the white dwarf - like a particularly violent ... 04:59: Just replace the white dwarf with a neutron star or black hole. 09:38: The white dwarf in these systems builds up mass until releasing it as a nova. 09:47: The rest stays with the white dwarf, which slowly grows in mass. 09:51: Eventually, the core of the white dwarf reaches a temperature of hundred of millions of Kelvin, and the star’s carbon and oxygen can begin to fuse. 04:38: ... bright X-ray light is emitted as the gas hits the polar regions of the white dwarf - like a particularly violent ... 03:07: ... finally identified a nearby flaring white dwarf binary - a so-called cataclysmic variable - and realized that it was the same ... 09:51: Eventually, the core of the white dwarf reaches a temperature of hundred of millions of Kelvin, and the star’s carbon and oxygen can begin to fuse. 01:22: ... storm of fusion ripped around the planet-sized white dwarf, spraying its atmosphere into space and for a couple of weeks shining 10s of ... 02:16: ... we’re going to look at the worst of these - from the novae produced by white dwarfs, to X-ray binaries created by neutron stars and black holes - and much ...
	2020-06-22: Building Black Holes in a Lab 05:01: ... is in the opposite direction to the waves this is actually an analog white hole. Other experiments use a carefully-shaped hole in a tank to create ...
	2020-05-18: Mapping the Multiverse 09:45: It leads to what looks like a white hole. 09:49: Now we saw that in the Schwarzschild solution, a white hole exists in the past of a purely hypothetical eternal non-rotating black hole. 10:00: The Kerr black hole also has a white hole in the past, but it has one in the future too. 10:18: You caught a glimpse of the entire history of that universe the moment you crossed into the white hole. 10:25: That white hole will eject you as forcibly as the black hole pulled you down. 10:49: If you try to head back to the white hole, you won’t find it - you’ll only find a new black hole that lies in its future. 09:45: It leads to what looks like a white hole. 09:49: Now we saw that in the Schwarzschild solution, a white hole exists in the past of a purely hypothetical eternal non-rotating black hole. 10:00: The Kerr black hole also has a white hole in the past, but it has one in the future too. 10:18: You caught a glimpse of the entire history of that universe the moment you crossed into the white hole. 10:25: That white hole will eject you as forcibly as the black hole pulled you down. 10:49: If you try to head back to the white hole, you won’t find it - you’ll only find a new black hole that lies in its future. 09:49: Now we saw that in the Schwarzschild solution, a white hole exists in the past of a purely hypothetical eternal non-rotating black hole.
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 04:50: ... universe. The black hole also has a mirror reflection that we call the white ... 05:17: ... you could potentially reach this strange point - the nexus between the white and black ... 04:50: ... universe. The black hole also has a mirror reflection that we call the white hole. ...
	2020-03-31: What’s On The Other Side Of A Black Hole? 06:15: ... looks just like the black hole - but with time reversed. This is the white hole, and we’ve this before - but perhaps we’ll get a little more ... 09:39: ... where opinion is divided. Some think that the parallel universe AND the white hole are just coordinate reflections of the regular universe and black ... 09:55: ... depends on how that reflection works. Perhaps you emerge from the past “white hole” traveling forward in time, or from the future black hole but ... 10:35: ... parallel universe and white hole are needed in the map of the eternal Schwarzschild black hole in ... 06:15: ... looks just like the black hole - but with time reversed. This is the white hole, and we’ve this before - but perhaps we’ll get a little more insight into ... 09:39: ... where opinion is divided. Some think that the parallel universe AND the white hole are just coordinate reflections of the regular universe and black hole - ... 09:55: ... depends on how that reflection works. Perhaps you emerge from the past “white hole” traveling forward in time, or from the future black hole but traveling ... 10:35: ... parallel universe and white hole are needed in the map of the eternal Schwarzschild black hole in order ... 09:55: ... depends on how that reflection works. Perhaps you emerge from the past “white hole” traveling forward in time, or from the future black hole but traveling backwards ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 00:21: The Heisenberg cut - is it the share of proceeds you send to Walter White to avoid, well, getting cut?
	2020-01-06: How To Detect a Neutrino 09:42: ... Ansar" (bright teal heart symbol) ♥ (text) "KORNHABERBROWN" (image: white PBS logo on navy background) (white text - slides out from behind logo) ...
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... soldier of ministereth in the background there but wasn't he Gandalf the White not the gray by the time the fellowshipped reached the tower of watch oh ...
	2019-03-20: Is Dark Energy Getting Stronger? 04:02: Type-1a supernovae– which result from exploding white dwarf stars. 16:37: IT's called launcherone, and it'll launch from WhiteKnightTwo - the same plane that carries spaceshiptwo.
	2019-03-13: Will You Travel to Space? 05:59: Unity is dropped at 15,000 meters by its carrier, White Night, after which it blasts it's rocket engine sending it into a sub-orbital flight.
	2019-01-24: The Crisis in Cosmology 04:41: These result when white dwarfs, ancient remnants of dead stars,... 17:01: ...should transform it into a white hole. 04:41: These result when white dwarfs, ancient remnants of dead stars,... 17:01: ...should transform it into a white hole.
	2018-08-30: Is There Life on Mars? 02:06: ... surface, and so measure Mars's 24-hour rotation rate, as well as a white spot on its south ... 02:45: The white spot was indeed a polar ice cap. 02:06: ... surface, and so measure Mars's 24-hour rotation rate, as well as a white spot on its south ... 02:45: The white spot was indeed a polar ice cap.
	2018-08-23: How Will the Universe End? 00:27: ... expand, the final atoms of hydrogen fuel and settle quietly into a dim white dwarf before slowly fading to black as it radiates away its remaining ... 02:32: ... stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including the recently extinguished ... 02:51: Those white dwarfs will fade to black in only several billion years, far shorter than the several trillion-year lives of those stars. 04:05: But neutron stars and white-- or, by now, black-- dwarfs are made of degenerate matter. 00:27: ... expand, the final atoms of hydrogen fuel and settle quietly into a dim white dwarf before slowly fading to black as it radiates away its remaining ... 02:32: ... stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including the recently extinguished red ... 02:51: Those white dwarfs will fade to black in only several billion years, far shorter than the several trillion-year lives of those stars. 02:32: ... stars and black holes from long-extinct massive stars, as well as the white dwarfs left from lower-mass stars, including the recently extinguished red ...
	2018-06-20: The Black Hole Information Paradox 02:40: Hawking radiation is like a cosmic whiteboard eraser.
	2018-05-09: How Gaia Changed Astronomy Forever 03:06: After which, lower mass stars will become red giants, before leaving behind white dwarf remnants. 03:32: We also see the full sequence of faint white dwarfs, showing the paths they follow as they slowly fade into blackness. 03:39: ... evolutionary paths that may reveal the composition and past life of the white ... 03:51: We see hot, newly formed white dwarfs, some of which are still embedded in the nebula of gas injected in the death of their star. 08:54: Selman123 asks about the difference between a white dwarf and a red dwarf. 09:03: A white dwarf is the remnant core of a low to mid-mass star after it burns out and ejects its outer layers, leaving only the hot core. 09:11: White dwarfs aren't necessarily white. 09:13: They start out blue and are expected to eventually fade, through white to red to black, but we always call them, white dwarfs. 09:26: And we expect them to pass through white, and some to blue, at the ends of their lives. 09:33: Until they burn out, and then, they're white dwarfs. 03:06: After which, lower mass stars will become red giants, before leaving behind white dwarf remnants. 03:39: ... evolutionary paths that may reveal the composition and past life of the white dwarf. ... 08:54: Selman123 asks about the difference between a white dwarf and a red dwarf. 09:03: A white dwarf is the remnant core of a low to mid-mass star after it burns out and ejects its outer layers, leaving only the hot core. 03:06: After which, lower mass stars will become red giants, before leaving behind white dwarf remnants. 03:32: We also see the full sequence of faint white dwarfs, showing the paths they follow as they slowly fade into blackness. 03:51: We see hot, newly formed white dwarfs, some of which are still embedded in the nebula of gas injected in the death of their star. 09:11: White dwarfs aren't necessarily white. 09:13: They start out blue and are expected to eventually fade, through white to red to black, but we always call them, white dwarfs. 09:33: Until they burn out, and then, they're white dwarfs. 03:32: We also see the full sequence of faint white dwarfs, showing the paths they follow as they slowly fade into blackness.
	2018-05-02: The Star at the End of Time 00:47: And finally, our heirs or successors find new homes among the stars after the Sun's final death and transformation into a dim white dwarf. 05:46: First, they shine white as their black-body spectrum spans the visible range, just like our Sun. 06:00: ... will become composed of helium and will quietly contract into a helium white dwarf, supported by quantum mechanical electron degeneracy ... 06:33: ... billion years from now, but they will have expired, leaving their own white ... 06:43: And those white dwarfs will have faded long before the first red dwarf passes away. 07:03: Individual points of white light will appear in the night sky, shining for up to a few billion years before winking out. 00:47: And finally, our heirs or successors find new homes among the stars after the Sun's final death and transformation into a dim white dwarf. 06:00: ... will become composed of helium and will quietly contract into a helium white dwarf, supported by quantum mechanical electron degeneracy ... 06:33: ... billion years from now, but they will have expired, leaving their own white dwarfs. ... 06:43: And those white dwarfs will have faded long before the first red dwarf passes away. 07:03: Individual points of white light will appear in the night sky, shining for up to a few billion years before winking out.
	2018-04-25: Black Hole Swarms 06:32: Polars are a bit like X-ray binaries, except instead of a black hole or a neutron star, you have a white dwarf with a powerful magnetic field. 06:39: ... the companion star to build up and then, fall very suddenly onto the white dwarf, producing a burst of ... 06:32: Polars are a bit like X-ray binaries, except instead of a black hole or a neutron star, you have a white dwarf with a powerful magnetic field. 06:39: ... the companion star to build up and then, fall very suddenly onto the white dwarf, producing a burst of ...
	2018-04-18: Using Stars to See Gravitational Waves 04:34: ... black holes, as well as the faint hum of thousands of binary pairs of white dwarfs, neutron stars, and black holes long before they ... 08:03: A similar effect may cause white dwarf stars in binary orbits to explode as they absorb gravitational radiation from their own orbits. 04:34: ... black holes, as well as the faint hum of thousands of binary pairs of white dwarfs, neutron stars, and black holes long before they ...
	2018-03-07: Should Space be Privatized? 11:48: ... that point, the whole thing becomes a white dwarf, but without the dramatic cycle of shell burning and red giant ...
	2018-02-21: The Death of the Sun 07:18: The sun has become a white dwarf. 07:46: It's also possible that the iron core survives and will continue to orbit the white dwarf sun until the end of everything. 07:18: The sun has become a white dwarf. 07:46: It's also possible that the iron core survives and will continue to orbit the white dwarf sun until the end of everything.
	2017-11-22: Suicide Space Robots 13:00: A few of you point out that the EM drive now has a peer reviewed paper coming from Harold white at NASA's Eagle Works Laboratories. 13:26: And there was a long list of systematic errors that may have been to blame, which Harold White listed with admirable honesty.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 14:47: Regarding our episode on white holes, a few of you wanted some clarification of a point I made. 14:53: I said that the Big Bang is mathematically similar to a white hole, except that it doesn't possess a singularity. 15:13: Now, we can imagine both the white hole and the earliest instant of the Big Bang as possessing infinite or at least extremely high density. 15:21: But for the Big Bang, that density is everywhere, not concentrated at a single point, as in the case of the white hole. 14:53: I said that the Big Bang is mathematically similar to a white hole, except that it doesn't possess a singularity. 15:13: Now, we can imagine both the white hole and the earliest instant of the Big Bang as possessing infinite or at least extremely high density. 15:21: But for the Big Bang, that density is everywhere, not concentrated at a single point, as in the case of the white hole. 14:47: Regarding our episode on white holes, a few of you wanted some clarification of a point I made.
	2017-08-30: White Holes 00:14: In fact, it's the black hole's mirror twin-- the white hole. 01:18: One such entity is the white hole. 01:21: A white hole is the opposite of a black hole in a very literal mathematical sense. 01:41: That makes a white hole a region of outward flowing space time. 01:51: Nothing outside a white hole can ever enter, and everything inside must be ejected. 01:56: Not even light can leave a black hole, hence the whole black thing, but light can only leave a white hole. 02:05: So these might be expected to radiate like crazy, and white would be an understatement. 02:12: ... before everyone gets too excited, white holes are probably a figment of mathematical imagination, but they're a ... 02:26: White holes first emerged in the very earliest mathematical description of black holes. 07:51: So far, this region fits perfectly the description of a white hole. 07:56: The eternal black hole of the past technically is a white hole. 08:06: One, light rays exiting that past white hole can never reach us. 08:34: Even though this type of white hole isn't observable, some physicists have taken the description very seriously. 08:41: The math describing the white hole is a perfectly good use of the Schwarzschild metric. 09:01: So can new white holes actually form? 09:12: ... although it's possible to build a white hole in general relativity, there are other laws of physics that the ... 09:46: ... rare entropy dip could lead to an effective reversal of time and a white hole could ... 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. 10:18: ... it happens, the Big Bang looks-- mathematically, at least-- much like a white ... 10:43: The difference between the Big Bang and a white hole is that the former possesses no singularity. 10:57: It's been proposed that, when a black hole forms, a white hole forms on the opposite side. 11:04: Energy entering the black hole exits the white hole. 11:08: ... Lee Smolin takes it a step further to suggest that the resulting white hole is the Big Bang of a new baby universe and that, in fact, our ... 11:32: The past white hole was revealed when we traced the eternal black hole backwards in time. 00:14: In fact, it's the black hole's mirror twin-- the white hole. 01:18: One such entity is the white hole. 01:21: A white hole is the opposite of a black hole in a very literal mathematical sense. 01:41: That makes a white hole a region of outward flowing space time. 01:51: Nothing outside a white hole can ever enter, and everything inside must be ejected. 01:56: Not even light can leave a black hole, hence the whole black thing, but light can only leave a white hole. 07:51: So far, this region fits perfectly the description of a white hole. 07:56: The eternal black hole of the past technically is a white hole. 08:06: One, light rays exiting that past white hole can never reach us. 08:34: Even though this type of white hole isn't observable, some physicists have taken the description very seriously. 08:41: The math describing the white hole is a perfectly good use of the Schwarzschild metric. 09:12: ... although it's possible to build a white hole in general relativity, there are other laws of physics that the universe ... 09:46: ... rare entropy dip could lead to an effective reversal of time and a white hole could ... 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. 10:18: ... it happens, the Big Bang looks-- mathematically, at least-- much like a white hole. ... 10:43: The difference between the Big Bang and a white hole is that the former possesses no singularity. 10:57: It's been proposed that, when a black hole forms, a white hole forms on the opposite side. 11:04: Energy entering the black hole exits the white hole. 11:08: ... Lee Smolin takes it a step further to suggest that the resulting white hole is the Big Bang of a new baby universe and that, in fact, our universe ... 11:32: The past white hole was revealed when we traced the eternal black hole backwards in time. 10:57: It's been proposed that, when a black hole forms, a white hole forms on the opposite side. 08:34: Even though this type of white hole isn't observable, some physicists have taken the description very seriously. 02:12: ... before everyone gets too excited, white holes are probably a figment of mathematical imagination, but they're a ... 02:26: White holes first emerged in the very earliest mathematical description of black holes. 09:01: So can new white holes actually form?
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 01:31: To our eyes it twinkles bluish white on the night sky.
	2017-01-19: The Phantom Singularity 12:36: ... our Patreon Google Hangout where he pretty much obliterated the entire white hole hypothesis by correctly pointing out that if they existed in any ... 12:53: ... week, we inaugurated the "Space Time" Journal Club by looking at Harold White et al's paper on an apparently positive vacuum test of the EM ... 12:36: ... our Patreon Google Hangout where he pretty much obliterated the entire white hole hypothesis by correctly pointing out that if they existed in any great ...
	2017-01-11: The EM Drive: Fact or Fantasy? 01:23: ... one of the Space Time Journal Club, we're jumping into Harold "Sonny" White, et al., 2016 "Measurement of Impulsive Thrust from a Closed ... 08:05: ... two separate papers, Harold White performs computer simulations, which he argues demonstrates that such a ...
	2016-12-08: What Happens at the Event Horizon? 11:04: And down here we have what we call a white hole. 14:14: ... the recent paper out of Eagle Works Labs, Herald White and collaborators present some results on the thrust produced by their ... 11:04: And down here we have what we call a white hole.
	2016-11-09: Did Dark Energy Just Disappear? 00:37: These exploding white dwarf stars have predictable brightnesses that allow astronomers to figure out how far away they are. 02:52: However, in the 18 years since the first studies, we've observed a lot more of these exploding white dwarfs. 00:37: These exploding white dwarf stars have predictable brightnesses that allow astronomers to figure out how far away they are. 02:52: However, in the 18 years since the first studies, we've observed a lot more of these exploding white dwarfs.
	2016-07-06: Juno to Reveal Jupiter's Violent Past 10:38: So many of you, including Neil deGrasse Tyson, point out that the sun is actually white and not yellow. 10:46: ... the sun usually appears white to our eyes and so to our brains, and since the entire concept of color ... 11:00: But this observed whiteness is a result of the fact that our color sensitivity is limited. 11:25: Our eyes can't register the difference in brightness across the visible part of the spectrum, so we register the color as white. 11:00: But this observed whiteness is a result of the fact that our color sensitivity is limited.
	2016-05-25: Is an Ice Age Coming? 07:12: You might be wondering, when are the glaciers going to rush down from the north, bringing polar bears, white walkers, Tontons?
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 11:03: ... need some sort of luminosity reference point before we can start using white dwarf supernovae or Type 1a supernovae, the standard ... 11:25: We do that by finding independent distances to white dwarf supernovae in nearby galaxies. 11:03: ... need some sort of luminosity reference point before we can start using white dwarf supernovae or Type 1a supernovae, the standard ... 11:25: We do that by finding independent distances to white dwarf supernovae in nearby galaxies. 11:03: ... need some sort of luminosity reference point before we can start using white dwarf supernovae or Type 1a supernovae, the standard ... 11:25: We do that by finding independent distances to white dwarf supernovae in nearby galaxies.
	2016-04-27: What Does Dark Energy Really Do? 03:51: It's a type Ia or white dwarf supernova. 03:55: Take a white dwarf, the leftover core of a dead, low-mass star like our sun, and let it cannibalize some of the material from a binary companion. 04:24: When you catch a white dwarf supernova, you know its distance and redshift. 06:03: ... separate teams of astronomers spent years catching white dwarf supernovae exploding in galaxies billions of light years away to ... 09:19: That's what we see in our white dwarf supernova measurements. 03:51: It's a type Ia or white dwarf supernova. 03:55: Take a white dwarf, the leftover core of a dead, low-mass star like our sun, and let it cannibalize some of the material from a binary companion. 04:24: When you catch a white dwarf supernova, you know its distance and redshift. 06:03: ... separate teams of astronomers spent years catching white dwarf supernovae exploding in galaxies billions of light years away to measure ... 09:19: That's what we see in our white dwarf supernova measurements. 03:51: It's a type Ia or white dwarf supernova. 04:24: When you catch a white dwarf supernova, you know its distance and redshift. 09:19: That's what we see in our white dwarf supernova measurements. 06:03: ... separate teams of astronomers spent years catching white dwarf supernovae exploding in galaxies billions of light years away to measure the past ...
	2016-04-06: We Are Star Stuff 05:24: And in most cases, remains locked forever inside the final white dwarf. 08:47: ... a white dwarf, a remnant of a low mass star like the sun, has a binary partner ... 05:24: And in most cases, remains locked forever inside the final white dwarf. 08:47: ... a white dwarf, a remnant of a low mass star like the sun, has a binary partner star and ...
	2016-02-11: LIGO's First Detection of Gravitational Waves! 06:48: ... see the slow ringing of binary white dwarf stars in our own galaxy, as well as the final dance of pairs of ...
	2015-11-18: 5 Ways to Stop a Killer Asteroid 05:47: Seriously, arm a spacecraft with a cosmic-sized can of spray paint, and color one side of the asteroid white.
	2015-08-27: Watch THIS! (New Host + Challenge Winners) 03:19: ... with Andromeda doesn't disrupt our planetary system, it'll be a white dwarf remnant, and after the sun ejects its outer layers, there's a ... 04:00: Let's go to the white board. 03:19: ... with Andromeda doesn't disrupt our planetary system, it'll be a white dwarf remnant, and after the sun ejects its outer layers, there's a planetary ...
	2015-07-02: Can a Circle Be a Straight Line? 08:12: ... of "Spacetime." Last week we asked whether Australia would ever get a White Christmas in order to discuss the calendar, the seasons, and their ... 08:55: Australian white Christmas was just a motif for talking about reversal of the seasons relative to the calendar. 09:00: ... and QuannanHade, namely that Santa's sleigh is already pulled by six white boomers, or older white furred ... 08:12: ... of "Spacetime." Last week we asked whether Australia would ever get a White Christmas in order to discuss the calendar, the seasons, and their connection to ... 08:55: Australian white Christmas was just a motif for talking about reversal of the seasons relative to the calendar. 09:00: ... that Santa's sleigh is already pulled by six white boomers, or older white furred ...
	2015-06-24: The Calendar, Australia & White Christmas 02:01: ... change, wouldn't that mean Christmas on the beach for the north and white Christmas for the south after a few thousand years or so, depending on ... 02:37: ... always remain close to the spring equinox, which prevents a southern white Christmas by ... 04:14: Other factors could bring the south a white Christmas even sooner. 02:01: ... change, wouldn't that mean Christmas on the beach for the north and white Christmas for the south after a few thousand years or so, depending on exactly ... 02:37: ... always remain close to the spring equinox, which prevents a southern white Christmas by ... 04:14: Other factors could bring the south a white Christmas even sooner.
	2015-06-03: Is Gravity An Illusion? 01:11: ... to pause me right now and go watch this super awesome 1960s black and white video from MIT all about frames of ...

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