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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 ...

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 ...

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.

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 ...

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 ...

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.

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 ...

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.

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.

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 ...

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.

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.

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.

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 ...

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 ...

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.

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.

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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