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	2022-12-08: How Are Quasiparticles Different From Particles? 07:56: ... traveling through a circuit encounter resistance - basically, they have collisions, which can be electromagnetic interactions with other electrons, falling ...
	2022-11-23: How To See Black Holes By Catching Neutrinos 09:47: And collisions of magnetic-field-accelerated particles is exactly how we make neutrinos in our experiments.
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 18:29: ... Also some transient phenomena - like supernovae, or cosmic ray collisions. ...
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 03:24: ... we haven’t waited long enough, because we have yet to spot even a single collision compatible with the dark matter particle ... 04:48: ... some theorists believe we could see this, by looking at the high-energy collisions of standard model particles in collider experiments like the ... 05:17: All sorts of exotic particles get created in those collisions. 05:21: Those particles are sometimes detected directly when they smash into one of the many detectors surrounding the collision point. 08:48: ... us that the product of velocity times mass of all particles going into a collision has to be the same as the same product for all particles going ... 09:00: ... know pretty well the momentum of the particles going into our collision, and we can measure and add up the momentum of all the final state ... 09:42: Total moment in a collision is conserved, but also the momentum in each separate direction is conserved independently of the other directions. 10:01: ... various collision products can scatter in any direction, forwards, back or sideways. But ... 03:24: ... we haven’t waited long enough, because we have yet to spot even a single collision compatible with the dark matter particle ... 05:21: Those particles are sometimes detected directly when they smash into one of the many detectors surrounding the collision point. 10:01: ... various collision products can scatter in any direction, forwards, back or sideways. But any of ... 04:48: ... some theorists believe we could see this, by looking at the high-energy collisions of standard model particles in collider experiments like the ... 05:17: All sorts of exotic particles get created in those collisions.
	2022-08-24: What Makes The Strong Force Strong? 01:48: ... others realized that the way these particles were created in particle collisions suggested the existence of a new conserved quantity that they named ... 17:19: ... see it in cataclysmic astrophysical events - the various explosions and collisions we see out ... 01:48: ... others realized that the way these particles were created in particle collisions suggested the existence of a new conserved quantity that they named ... 17:19: ... see it in cataclysmic astrophysical events - the various explosions and collisions we see out ... 01:48: ... others realized that the way these particles were created in particle collisions suggested the existence of a new conserved quantity that they named ...
	2022-06-01: What If Physics IS NOT Describing Reality? 15:25: ... Kosa asks about actual collisions between  stars when galaxies merge. Given that most of ...
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 00:00: ... observing that night. But astronomers   watching the resulting collision in around 2  billion years might have more cause for ... 13:17: ... massive as the Milky Way. We’ve gone into the gory  detail of this collision in a previous episode.   Go ahead and watch that one if you ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 00:00: ... mass of the W boson. They spent nearly a   decade recording collisions in the Tevatron  collider and another decade analysing the ...
	2022-03-16: What If Charge is NOT Fundamental? 03:29: ... and at the same time allowed precise predictions of the outcome of  collisions between these ...
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 08:50: ... them at near the speed of light.   This inevitably leads to collisions  between segments of strings–either   two distinct strings or ...
	2022-01-27: How Does Gravity Escape A Black Hole? 15:39: ... by the simulations we showed of the inevitable collision of the Milky Way with the Andomeda Galaxy, Robert Herd asks the ... 16:25: ... speaking of the Milky Way-Andromeda collision, Roli Rivelino points out that way back in our 3-body problem video, they ... 16:44: For those who missed the answer - we know that the collision will happen because we simulated it. 16:25: ... speaking of the Milky Way-Andromeda collision, Roli Rivelino points out that way back in our 3-body problem video, they ...
	2022-01-19: How To Build The Universe in a Computer 00:30: ... a series of whirling collisions, all spiral structure will be obliterated, gas will be compacted to ... 00:59: And simulations of galaxy collisions are just the beginning. 08:45: ... formation,   and even star and planet destruction  in collisions or ... 00:30: ... a series of whirling collisions, all spiral structure will be obliterated, gas will be compacted to ... 00:59: And simulations of galaxy collisions are just the beginning. 08:45: ... formation,   and even star and planet destruction  in collisions or ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 15:46: ... these scientists think that, that's less likely that the white dwarf collision explanation, which at any rate we know must happen at least ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 09:18: ... 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 ... 09:51: ... generated by dynamos - self-sustaining currents of charged particles. A collision like this could well produce the sort of turbulent motion to jump start ...
	2021-07-13: Where Are The Worlds In Many Worlds? 02:30: ... complex fluctuation at their collision seems to hold no record of the shapes of the incoming waves, and yet its ...
	2021-06-09: Are We Running Out of Space Above Earth? 00:46: ... we cross the threshold into the chain reaction of exponentially growing collisions known as Kessler ... 01:40: A collision with one of these means instant obliteration into countless shards. 02:23: Space is, as the name implies, spacious, and so collisions are relatively rare, or at least for the moment they're rare. 02:31: But as the number of satellites increases, the risk of collisions also increases. 02:37: And collisions produce more space junk that produces more collisions. 02:41: This sort of collision cascade is known as the Kessler Syndrome, after Donald Kessler who pointed out the danger in 1978. 03:34: In the case of satellite collisions, exponential increase is inevitable unless debris is removed from orbit or the risk of collision is mitigated. 03:59: And their future trajectories can be calculated to predict possible future collisions. 05:03: And yet are still large enough to cause ‘lethal’ collisions- the kind that can obliterate a satellite if they hit right in the main body. 05:29: Junk smaller than around a centimeter can’t be tracked at all - your paint flecks and rocket exhaust and shards from prior collisions. 06:26: Ultimately, the Kessler Syndrome can be avoided if orbital decay cleans up low-earth orbit faster than new launches and new collisions fill it. 06:59: Notably we have the 2009 collision between the Iridium 33 communication satellite and Kosmos 2251, a deactivated Soviet military satellite. 07:09: ... a collision velocity of 11.6km/s, it was less a smash than a splash, creating ... 08:23: This increases the altitude range of the risk, and can also mean that collisions in fast-decaying orbits can still generate long-lasting debris. 08:37: Each collision tends to populate a wide swath of low-earth-orbit with dangerous debris. 08:54: ... Station orbits several hundred kilometers below where the Iridium-Kosmos collision happened, on multiple occasions it's had to perform collision avoidance ... 09:31: So how long until the collision cascade? 09:45: ... 1978, Donald Kessler estimated that the first satellite collision would probably happen some time in the next two to three decades, which ... 09:58: But the time to the next collision should be shorter - and indeed there have been several now, although thankfully none as cataclysmic as the first. 10:34: Now SpaceX insists that they have collision mitigation systems planned, even if they haven’t told us exactly what those are. 10:41: But even the best collision dodger can’t do much against an untracked and untrackable shard of debris. 12:02: ... over from launches to high altitudes- maybe they could be destroyed in collisions in low earth orbit, creating a train of debris that wreaks havoc higher ... 08:54: ... collision happened, on multiple occasions it's had to perform collision avoidance maneuvers to avoid debris that’s sinking through its ... 02:41: This sort of collision cascade is known as the Kessler Syndrome, after Donald Kessler who pointed out the danger in 1978. 09:31: So how long until the collision cascade? 10:41: But even the best collision dodger can’t do much against an untracked and untrackable shard of debris. 08:54: ... Station orbits several hundred kilometers below where the Iridium-Kosmos collision happened, on multiple occasions it's had to perform collision avoidance maneuvers ... 10:34: Now SpaceX insists that they have collision mitigation systems planned, even if they haven’t told us exactly what those are. 07:09: ... a collision velocity of 11.6km/s, it was less a smash than a splash, creating hundreds of ... 00:46: ... we cross the threshold into the chain reaction of exponentially growing collisions known as Kessler ... 02:23: Space is, as the name implies, spacious, and so collisions are relatively rare, or at least for the moment they're rare. 02:31: But as the number of satellites increases, the risk of collisions also increases. 02:37: And collisions produce more space junk that produces more collisions. 03:34: In the case of satellite collisions, exponential increase is inevitable unless debris is removed from orbit or the risk of collision is mitigated. 03:59: And their future trajectories can be calculated to predict possible future collisions. 05:03: And yet are still large enough to cause ‘lethal’ collisions- the kind that can obliterate a satellite if they hit right in the main body. 05:29: Junk smaller than around a centimeter can’t be tracked at all - your paint flecks and rocket exhaust and shards from prior collisions. 06:26: Ultimately, the Kessler Syndrome can be avoided if orbital decay cleans up low-earth orbit faster than new launches and new collisions fill it. 08:23: This increases the altitude range of the risk, and can also mean that collisions in fast-decaying orbits can still generate long-lasting debris. 12:02: ... over from launches to high altitudes- maybe they could be destroyed in collisions in low earth orbit, creating a train of debris that wreaks havoc higher ... 03:34: In the case of satellite collisions, exponential increase is inevitable unless debris is removed from orbit or the risk of collision is mitigated. 02:37: And collisions produce more space junk that produces more collisions.
	2021-01-26: Is Dark Matter Made of Particles? 04:15: If it did, then giant regions of dark matter would lose energy in those collisions and contract.
	2021-01-19: Can We Break the Universe? 11:34: But there’s no collision, because the nose of the spaceship exists in the future, and the tail in the past. 11:44: ... spaceship travels, it will only elongate along this helix - safe from collision even if it wraps around the universe multiple ...
	2020-12-15: The Supernova At The End of Time 13:26: A future collision between two objects is "remembered" by their current movement toward each other. 13:37: ... information of a future collision is spread out, spatially, before the collision: to "remember" the future ... 13:48: After the collision, you can find information about that collision recorded in each of the objects.
	2020-12-08: Why Do You Remember The Past But Not The Future? 02:55: ... holds a “memory” of past collisions in the chips and dents on its surface, it recalls being hit by cosmic ... 03:52: Well, more collisions building it up or breaking it down, more cosmic ray hits, that sort of thing. 02:55: ... holds a “memory” of past collisions in the chips and dents on its surface, it recalls being hit by cosmic ... 03:52: Well, more collisions building it up or breaking it down, more cosmic ray hits, that sort of thing.
	2020-11-18: The Arrow of Time and How to Reverse It 03:47: Over time, energy tends to get shared out as evenly as possible due to, say, collisions. 03:53: ... out and it would stay shared out. It’s very unlikely that through random collisions, half the electrons would get all the energy and the other half end up ... 03:47: Over time, energy tends to get shared out as evenly as possible due to, say, collisions. 03:53: ... out and it would stay shared out. It’s very unlikely that through random collisions, half the electrons would get all the energy and the other half end up ...
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 02:16: ... are falling directly towards each   other on a perfect collision course, the  math has to land them all in the ...
	2020-09-08: The Truth About Beauty in Physics 15:30: This is nowhere near as big as even the large hadron collider, but it does achieve higher luminosities - more collisions per second. 15:49: To detect these you need more collisions, not higher energies. 15:30: This is nowhere near as big as even the large hadron collider, but it does achieve higher luminosities - more collisions per second. 15:49: To detect these you need more collisions, not higher energies.
	2020-08-24: Can Future Colliders Break the Standard Model? 01:55: ... those first collision experiments, all sorts of never-before-seen particles were observed ... 02:10: To be precise, collision energy with a fixed target goes up with the square root of accelerator energy. 03:08: In collider-speak, luminosity is a measure of the number of particle collisions across an area over a time period. 03:15: More collisions means more chance of producing weird particles. 03:29: Finally we’d reached collision energies needed to test predictions of the still relatively new quantum electrodynamics. 04:09: ... generated collisions energetic enough to produce the very massive top quark, and so enabled ... 07:41: ... a new particle we need to watch the result of billions of billions of collisions - we need very high ... 09:33: It’s easier to achieve the energies and luminosities to produce, for example, large numbers of Higgs particles in relatively clean collisions. 10:04: The FCC will eventually graduate to proton-proton collisions which will open up the discovery space further. 03:29: Finally we’d reached collision energies needed to test predictions of the still relatively new quantum electrodynamics. 02:10: To be precise, collision energy with a fixed target goes up with the square root of accelerator energy. 01:55: ... those first collision experiments, all sorts of never-before-seen particles were observed allowing ... 03:08: In collider-speak, luminosity is a measure of the number of particle collisions across an area over a time period. 03:15: More collisions means more chance of producing weird particles. 04:09: ... generated collisions energetic enough to produce the very massive top quark, and so enabled ... 07:41: ... a new particle we need to watch the result of billions of billions of collisions - we need very high ... 09:33: It’s easier to achieve the energies and luminosities to produce, for example, large numbers of Higgs particles in relatively clean collisions. 10:04: The FCC will eventually graduate to proton-proton collisions which will open up the discovery space further. 07:41: ... a new particle we need to watch the result of billions of billions of collisions - we need very high ... 04:09: ... generated collisions energetic enough to produce the very massive top quark, and so enabled the ...
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 00:29: ... infinitesimal ripples in the fabric of spacetime due to a cataclysmic collision of black holes billions of light years ... 03:34: ... - energy released as the neutron stars tore themselves apart in their collision before they collapsed into a black ...
	2020-06-15: What Happens After the Universe Ends? 13:28: Penroses proposes that the collisions of super massive black holes in the previous universe may leave rings on the sky in the next.
	2020-04-14: Was the Milky Way a Quasar? 04:49: The gamma rays produced by neutral pion decay from these cosmic ray collisions tend to drop off in intensity towards higher energies. 06:47: ... when that gas gets a shake - for example, if the galaxy is shaken by a collision or close interaction with another galaxy - then that gas can form stars ... 04:49: The gamma rays produced by neutral pion decay from these cosmic ray collisions tend to drop off in intensity towards higher energies.
	2020-01-20: Solving the Three Body Problem 14:24: ... the particles made in the interaction. From that, we can reconstruct the collision and learn more about ...
	2020-01-13: How To Capture Black Holes 03:34: ... a supermassive black hole sounds like a recipe for black hole collisions. Actually not so much - black holes are so compact that they never ...
	2019-11-04: Why We Might Be Alone in the Universe 07:27: The debris thrown up during this collision became our moon.
	2019-09-30: How Many Universes Are There? 12:51: But it still should NOT be surprising that we don’t see evidence of bubble collisions in our observable universe. 12:59: If such collisions happened, they’re probably too far away for us to see. 12:51: But it still should NOT be surprising that we don’t see evidence of bubble collisions in our observable universe. 12:59: If such collisions happened, they’re probably too far away for us to see.
	2019-08-06: What Caused the Big Bang? 11:51: ... appearance of a bubble can't be too high and that rules out sufficient collisions. ...
	2019-07-18: Did Time Start at the Big Bang? 09:52: ... in a higher dimensional space living on geometric objects called brains collisions between those brains initiate cycles of expansion of contraction Then ...
	2019-07-01: Thorium and the Future of Nuclear Energy 02:49: ... the same mass as neutrons they absorb a lot of momentum in Neutron collisions and Conveniently that same water can also work as a coolant. It takes ...
	2019-06-17: How Black Holes Kill Galaxies 12:04: ... the Fermi Paradox might be explained by the fact that neutron star collisions are rare so that only lucky parts of the galaxies have a high abundance ... 12:17: ... these collisions are rare they are common enough that most of the galaxy gets a decent ... 13:04: Tricky asks us why we don't see more strange matter from neutron star collisions. 14:07: or in the detailed shape of the gravitational wave signal before collision. 12:04: ... the Fermi Paradox might be explained by the fact that neutron star collisions are rare so that only lucky parts of the galaxies have a high abundance ... 12:17: ... these collisions are rare they are common enough that most of the galaxy gets a decent ... 13:04: Tricky asks us why we don't see more strange matter from neutron star collisions.
	2019-06-06: The Alchemy of Neutron Star Collisions 00:00: ... precious metals were produced in an even more spectacular events the collision of neutron ... 02:47: ... the subsequent electromagnetic flash as the ejected material from this collision expanded and faded the spectral signatures of many r-process elements ...
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... gas in these clusters collided and ended up left at the location of the collision while the galaxies moved on so where is the dark matter if modified ...
	2018-11-21: 'Oumuamua Is Not Aliens 16:34: Neutrinos are detected by the Cherenkov radiation produced by particles produced in neutrino collisions.
	2018-11-14: Supersymmetric Particle Found? 02:54: ... enough in the Large Hadron Collider, there'd be enough energy in those collisions to produce a supersymmetric ... 03:27: To detect more massive supersymmetric particles, you need higher energy particle collisions. 02:54: ... enough in the Large Hadron Collider, there'd be enough energy in those collisions to produce a supersymmetric ... 03:27: To detect more massive supersymmetric particles, you need higher energy particle collisions.
	2018-06-27: How Asteroid Mining Will Save Earth 03:18: These are the leftover cores of larger asteroids that were destroyed by collisions.
	2018-05-16: Noether's Theorem and The Symmetries of Reality 03:57: It doesn't matter when the collision happens, the results are the same.
	2018-05-02: The Star at the End of Time 06:33: ... new Sun-like stars will be born in the Milky Way/Andromeda collision four billion years from now, but they will have expired, leaving their ...
	2018-04-18: Using Stars to See Gravitational Waves 02:54: Observatories across the planet and in orbit around the planet swiveled to watch the afterglow of this collision.
	2018-03-28: The Andromeda-Milky Way Collision 01:10: At around four billion years from now, it'll crash through the Milky Way, and both galaxies will be utterly disrupted in the monumental collision. 04:58: A head-on collision is inevitable. 05:00: Van der Marel and team also ran a computer simulation to study the consequences of this collision. 05:43: We see these in other distant galaxies, like the Antennae, which are currently in the process of collision. 06:52: Well, for one thing, we don't expect any collisions between stars. 08:37: ... sometimes think how lucky we are to live in the time before our collision with Andromeda, a time when we have such a clear view of our dynamical ... 06:52: Well, for one thing, we don't expect any collisions between stars.
	2017-12-20: Extinction by Gamma-Ray Burst 01:01: ... what about the Milky Way's inevitable collision with Andromeda, or the final burning out of the last stars, or the ...
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 02:28: And it suggests a major collision in the object's past.
	2017-10-11: Absolute Cold 09:39: And when galaxies get stirred up by an interaction or collision with another galaxy, we expect that gas will be driven into the core also.
	2017-10-04: When Quasars Collide STJC 02:04: Or do they mostly grow when smaller SMBHs find each other and merge during galaxy collisions?
	2017-09-20: The Future of Space Telescopes 13:14: [INAUDIBLE] wants to confirm that the gold in their ring may have been created in the collision of two neutron stars.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 00:15: ... that LIGO had for the first time spotted gravitational waves from the collision of a pair of neutron ... 08:36: Well, beyond raw curiosity, it may be that neutron star collisions produce many of the heavier elements of the periodic table.
	2017-06-21: Anti-Matter and Quantum Relativity 12:17: ... cold spot in the cosmic microwave background was due to supervoids or a collision with another ... 14:30: ... the lower energy bubble, that's bad, at least in the region of the collision, because a ton of energy gets dumped into it from the high energy ...
	2017-06-07: Supervoids vs Colliding Universes! 00:30: Is that giant cold spot in the cosmic microwave background really evidence of a collision with another universe? 08:32: But the one that gets most people most excited is, of course, that the cold spot is the mark left due to a collision with another universe. 09:37: But regardless, in an infinitely inflating space time, collisions between bubble universes are eventually expected.
	2017-04-19: The Oh My God Particle 03:31: Higher energy cosmic rays tend to obliterate themselves several kilometers above the ground in massive collisions with nuclei of air molecules. 03:40: The result is a cascade of subatomic particles, the debris of the collision, that can spread itself out over several kilometers. 04:02: ... analyzing the energies and trajectories of the debris, the collision that produced them and the nature of the original cosmic ray can be ... 09:20: ... highest energy cosmic rays, like the Oh-My-God particle, generate collisions far more energetic than our largest particle accelerator, the Large ... 03:31: Higher energy cosmic rays tend to obliterate themselves several kilometers above the ground in massive collisions with nuclei of air molecules. 09:20: ... highest energy cosmic rays, like the Oh-My-God particle, generate collisions far more energetic than our largest particle accelerator, the Large ...
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 03:34: They grow in size until they're large enough that they can start collecting more material through collisions. 03:40: These collisions must be very gentle, or else pieces will shatter on impact. 07:20: Instead, it may be a collection of debris left over from a recent collision. 03:34: They grow in size until they're large enough that they can start collecting more material through collisions. 03:40: These collisions must be very gentle, or else pieces will shatter on impact.
	2016-11-16: Strange Stars 04:25: Minuscule flecks of quark-gluon plasma exist for tiny fractions of a second after very high-speed particle collisions.
	2016-10-12: Black Holes from the Dawn of Time 03:21: For example, the collapse of cosmic string moves and the collision of bubble universes?
	2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer 01:19: The same sort of excess in the photons emitted after proton collisions in the Large Hadron Collider led to the discovery of the Higgs boson.
	2016-08-10: How the Quantum Eraser Rewrites the Past 12:48: As for the death of the sun and Andromeda's collision with the Milky Way, OK.
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 01:16: The resulting collisions can produce temperatures of several trillion Kelvin. 01:39: Many, many weird particles come out of such a collision. 01:16: The resulting collisions can produce temperatures of several trillion Kelvin.
	2016-04-06: We Are Star Stuff 09:16: ... of the gold in the universe, were formed not in a supernova, but in the collision of two neutron ...
	2015-10-22: Have Gravitational Waves Been Discovered?!? 03:16: ... merger, or gravitational catastrophes like supernova explosions or collisions between giant black holes-- these make g-waves that lengthen or contract ...
	2015-09-23: Does Dark Matter BREAK Physics? 07:14: ... on Earth designed to catch the fall-out between the unthinkably rare collisions between a dark matter particle and an atomic ...
	2015-08-27: Watch THIS! (New Host + Challenge Winners) 03:19: ... assuming the collision with Andromeda doesn't disrupt our planetary system, it'll be a white ...
	2015-04-01: Is the Moon in Majora’s Mask a Black Hole? 00:00: [MUSIC PLAYING] In "The Legend of Zelda: Majora's Mask," Link needs to save Termina from an impending collision with that planet's malevolent moon. 00:25: Link arrives in Termina, a province on a planet whose moon is on a three-day collision course with the surface.
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 08:18: Lots of you asked whether Earth could suffer a collision when the Andromeda and Milky Way galaxies merge in about 4 billion years. 08:48: Again, extremely low odds of collision, even if there's hundreds of millions of those things flying around the Milky Way.
	2015-03-11: What Will Destroy Planet Earth? 02:18: In fact, a head-on collision between Earth and any solar system object deflected into our path will top out at a mere 70 to 80 kilometers per second. 03:33: So a Martian collision is possible, but is it likely?

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