Search PBS Space Time

What are you looking for?

	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 16:34: Some Kid and Cybernatural ask whether quasiparticles could be used to explain dark matter. 16:53: Dark matter suffuses the near-vacuum of space, where we mostly just have the elementary quantum fields.
	2022-10-19: The Equation That Explains (Nearly) Everything! 14:00: ... model or its lagrangian. In fact there probably are - whatever makes up dark matter for example. And there are other mysteries that this doesn’t explain. It ...
	2022-09-21: Science of the James Webb Telescope Explained! 12:19: ... and then the one about how the Higgs boson could tell us what dark matter really ... 15:23: OK, on to our episode on how the Higgs boson could be the key to discovering the dark matter particle. 17:21: ... we astrophysicists just get on with business and discover the big bang, dark matter and dark energy, and figure out how the universe is going to ... 15:23: OK, on to our episode on how the Higgs boson could be the key to discovering the dark matter particle.
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 00:19: But there are still many outstanding questions for example, it seems like nothing in the standard model can explain what dark matter is. 00:33: Many physicists think that the secret to finding the elusive dark matter particle will come by studying the Higgs. 01:31: And then there’s dark matter. 01:46: ... “dark matter” might be a new kind of particle, or, in fact, there could be an entire ... 02:37: This particular diagram shows a dark matter particle scattering off a standard model particle in some way. 02:50: ... would call this a direct detection experiment - because a dark matter particle is actually interacted with one of the particles in our say ... 03:00: Of course this sort of interaction is incredibly rare - otherwise we’d have detected dark matter already. 03:06: But with enough particles and enough time, we should eventually see an interaction between a dark matter particle and a matter particle. 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays. 03:24: ... because we have yet to spot even a single collision compatible with the dark matter particle ... 04:06: ... example, two dark matter particles somewhere in space could annihilate to produce gamma ray ... 04:18: If we were to find excess gamma radiation from high-density regions of our galaxy, then this might come from dark matter annihilations. 04:46: Now our annihilating dark matter. 04:48: ... become dark matter that’s created from the annihilation of some standard model particles. ... 05:35: But of all the particles produced in these events, we think that the elusive Higgs boson has the best shot at producing a dark matter particle. 06:30: ... could potentially decay into dark matter particles, but if they do it’s going to be near impossible to spot the ... 06:39: ... are ways to check whether dark matter and neutrinos are connected on cosmic scales by looking at the cosmic ... 06:55: ... Collider, but no evidence was found supporting interactions with dark matter, and so the Z is probably a dead ... 07:15: There’s good reason to think the Higgs might interact with dark matter. 07:24: Well, dark matter definitely has mass - that’s how we know it exists. 07:29: So it wouldn’t be too surprising if it turns out dark matter also gets its mass from the Higgs. 07:34: ... whole family of potential theories of how the Higgs could interact with dark matter, these all fall under the umbrella of Higgs portal ... 07:54: So, how exactly are we going to find dark matter via the Higgs? 08:14: But once we create them, how could we possibly tell if a Higgs decays into dark matter? 11:02: There are certain Higgs-generating reactions that are especially promising for our dark matter hunt. 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 13:08: ... era of Higgs physics, and we don’t know what it’ll reveal —- hopefully a dark matter particle, perhaps an entire dark sector, perhaps much ... 04:18: If we were to find excess gamma radiation from high-density regions of our galaxy, then this might come from dark matter annihilations. 03:14: So dark matter detectors consist of huge tubs of liquid or massive chunks of crystal, placed deep underground to avoid cosmic rays. 11:02: There are certain Higgs-generating reactions that are especially promising for our dark matter hunt. 00:33: Many physicists think that the secret to finding the elusive dark matter particle will come by studying the Higgs. 02:37: This particular diagram shows a dark matter particle scattering off a standard model particle in some way. 02:50: ... would call this a direct detection experiment - because a dark matter particle is actually interacted with one of the particles in our say ... 03:06: But with enough particles and enough time, we should eventually see an interaction between a dark matter particle and a matter particle. 03:24: ... because we have yet to spot even a single collision compatible with the dark matter particle ... 05:35: But of all the particles produced in these events, we think that the elusive Higgs boson has the best shot at producing a dark matter particle. 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 13:08: ... era of Higgs physics, and we don’t know what it’ll reveal —- hopefully a dark matter particle, perhaps an entire dark sector, perhaps much ... 04:06: ... example, two dark matter particles somewhere in space could annihilate to produce gamma ray photons, which ... 06:30: ... could potentially decay into dark matter particles, but if they do it’s going to be near impossible to spot the event, so ... 06:19: ... not interacting with light is the first defining characteristic of dark matter.We aren’t left with much in the standard ...
	2022-08-24: What Makes The Strong Force Strong? 20:15: Others use this coupling to explain dark energy AND dark matter. 20:27: Speaking of which, Marik Zilberman asked whether a particle of the quintessence field could account for Dark Matter? 21:17: Everyone knows that dark matter shot JFK.
	2022-08-17: What If Dark Energy is a New Quantum Field? 09:05: Alternatively, it can be thought of as a fifth energetic component of the universe on top of baryons, dark matter, neutrinos, and photons. 09:51: ... universe is dark energy with the remaining 30% mostly matter, including dark matter. ... 09:05: Alternatively, it can be thought of as a fifth energetic component of the universe on top of baryons, dark matter, neutrinos, and photons.
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 02:19: ... called globular clusters.   But mostly the halo is made of dark matter,  which also suffuses the disk and halo   and constitutes 80% of ...
	2022-03-16: What If Charge is NOT Fundamental? 14:52: My favorites are the fudge-filled hexaquarks, which are one of the most delicious candidates for dark matter.
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 19:51: ... and whether they could explain the cosmic microwave background and dark matter. ... 20:38: ... for dark matter - extremely unlikely - in our most accepted understanding of cosmic ... 20:48: But seriously guys one of the weird things we  talk about will turn out to be dark matter. 20:58: But let's hope it's never either. But  wait what if aliens are dark matter! 20:38: ... for dark matter - extremely unlikely - in our most accepted understanding of cosmic ...
	2022-01-19: How To Build The Universe in a Computer 00:47: ... and  hydrodynamic interactions of countless stars and gas and dark matter particles over billions of future ... 10:02: ... can watch as galaxies form, with gas and dark matter interacting to produce waves of star formation and supernovae, settling ... 10:28: It simulated 13-billion light years wide cube containing over 300 billion particles, each representing a billion-Suns worth of dark matter. 10:02: ... can watch as galaxies form, with gas and dark matter interacting to produce waves of star formation and supernovae, settling into spiral ... 00:47: ... and  hydrodynamic interactions of countless stars and gas and dark matter particles over billions of future ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 02:10: ... 86% of the mass of the universe, and are therefore an explanation for dark matter. ... 02:27: ... of the windows of possible masses if PBHs are to account for most of the dark matter. ... 03:25: ... for astronomers, and perhaps less fortunate for everyone else - if dark matter really is made of asteroid-mass black holes then there must be an ... 04:01: ... how much dark matter we know that there is in the Milky Way, we calculate that there's ... 04:26: ... hole hit the Earth we wouldn’t be destroyed - which is good, because if dark matter really is made of these things then it’s probably already happened. This ... 13:02: ... could lead to figuring out the nature of dark matter and to understanding the crazy black-hole-spawning chaos that defined ... 14:10: ... There was the one on modified newtonian dynamics as an explanation for dark matter, and the one on fuzzballs - the stringy theory version of the black ... 15:30: ... episode. And that's that we’ve observed galaxies that seem to be >99% dark matter as well as a few that seem to lack it entirely. He asks whether the new ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... my curiosity we really have to find out what is up with dark energy dark matter is cool but figuring out what dark energy really is it feels like ...
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 00:21: We’ve now been searching for dark matter for over half a century. 01:02: ... dubbed this hypothetical stuff dark matter, and of course we’ve talked about dark matter many times on this channel ... 01:39: ... for nearly as long as astronomers have been hunting for dark matter, others have been hunting for an alteration to our theory of gravity that ... 02:32: ... Dark matter is supposed to add extra mass that’s more evenly distributed through ... 02:43: Dark matter flattens rotation curves. 04:41: So MOND would need to do away with the need  for physical dark matter in the other places we see evidence for dark matter. 05:07: First, how does MOND do with respect to the other evidence for dark matter? 05:14: If you tune MOND to work for galaxies and then apply it to galaxy clusters, you do get rid of the need for some of the dark matter but not all of it. 05:22: You still need about 20% of the current dark matter requirement to explain all the gravity we see in clusters. 05:38: ... the fact that you still need some type of physical dark matter in clusters is seen as a strong point against MOND in its first ... 05:49: There are some other pieces of evidence for dark matter that O-G MOND also fails for, but I’ll come back to those. 06:47: ... such a tight relationship because the rotation velocity depends on the dark matter halo  while the luminosity depends on the ... 10:21: One of the most important pieces of evidence  for dark matter as a particle is seen in the light that comes from the very early universe. 10:51: But dark matter doesn’t interact with light, so it would have been able to collapse just fine. 10:58: ... to be released from the clutch of light, it could have followed the dark matter into its deep gravitational wells and get to the business of forming ... 11:12: But if dark matter isn’t real, and regular matter controls gravity completely, then no structure should have been able to form at those early times. 12:21: We don’t need dark matter, anymore? 12:33: ... I’ll just say that when galaxy clusters collide and the dark matter gets ripped away from the light matter - it makes you doubt that dark ... 13:10: ... MOND proponents say that it’s the behavior of  dark matter particles that have to be carefully fine-tuned to produce the phenomena ... 13:32: ... our experiments haven’t  detected dark matter yet, there are still plenty of possibilities for what it might be beyond ... 10:51: But dark matter doesn’t interact with light, so it would have been able to collapse just fine. 02:43: Dark matter flattens rotation curves. 06:47: ... such a tight relationship because the rotation velocity depends on the dark matter halo  while the luminosity depends on the ... 11:12: But if dark matter isn’t real, and regular matter controls gravity completely, then no structure should have been able to form at those early times. 01:02: ... this hypothetical stuff dark matter, and of course we’ve talked about dark matter many times on this channel - from the evidence for its existence to some of ... 13:10: ... MOND proponents say that it’s the behavior of  dark matter particles that have to be carefully fine-tuned to produce the phenomena that ... 05:22: You still need about 20% of the current dark matter requirement to explain all the gravity we see in clusters. 14:01: ... exploration of reality, whether we’re led beyond the standard model by dark matter  particles, or beyond general relativity by hidden gravitational modes of ... 00:03: What if there is no such thing as dark matter.   What if our understanding  of gravity is just wrong?
	2021-08-03: How An Extreme New Star Could Change All Cosmology 17:08: ... all have the answer I just gave - can magnetic fields be used to explain dark matter or to explain dark energy? Or could magnetic fields be used to power ...
	2021-06-09: Are We Running Out of Space Above Earth? 14:14: Last episode was on Planck Relics, those subatomic scale black holes that could be literally everywhere and even explain dark matter. 15:58: This is what makes them the perfect candidate for WIMPS - the weakly interacting massive objects that may explain dark matter.
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 08:19: ... from primordial black holes is that these could potentially explain dark matter. ... 08:35: And you’d need a lot to say the least because dark matter makes up 80% of the mass of the universe. 09:02: ... explaining Dark Matter, another reason to want Planck relics to be a thing is that they may ... 10:41: If Planck relics account for all of dark matter, are they around us right now?
	2021-05-11: How To Know If It's Aliens 14:35: ... two episodes: our update on warp drive theory, and the one about whether dark matter can be explained by enormous numbers of black holes - tldw - it probably ... 17:14: ... points out that there are scientists who have pushed the black hole dark matter hypothesis for years, so it hasn’t been overlooked as I implied at the ... 17:34: ... - molecular biology. Which is that the answer often lies in plurality. Dark matter might not be a single type of thing, but rather many different types of ... 18:02: ... as geniuses, many of you commented that you thought of the idea that dark matter is black holes years ago. That’s impressive - you’re in the company of ... 18:16: ... Dark matter ain’t black holes. That may have sounded unnecessarily snarky - and it ... 18:32: ... the truth. But it doesn't, hurt to check. I like this a lot. Looking for dark matter in, say, string theory, before you check whether it’s black holes is ... 18:16: ... Dark matter ain’t black holes. That may have sounded unnecessarily snarky - and it wasn’t ... 17:14: ... points out that there are scientists who have pushed the black hole dark matter hypothesis for years, so it hasn’t been overlooked as I implied at the beginning of ...
	2021-04-13: What If Dark Matter Is Just Black Holes? 00:09: Sounds horrible - but hey, at least we’d have explained dark matter. 00:25: This is dark matter, and it is one of the universe’s most perplexing mysteries. 00:30: ... days most dark matter hunters are trying to hypothesize or detect exotic new particles to ... 01:03: What if dark matter is just black holes? 01:06: These hyper-dense holes in the fabric of spacetime seem to be great dark matter candidates - being so black and holey and all. 01:25: ... real seems like a significant point in their favor as an explanation for dark matter - it’s more than we can say for any of the other dark matter particle ... 01:39: ... dark matter makes up roughly 80% of the mass of the universe, but it’s much more ... 01:53: ... for black holes to be dark matter they’d need to be abundant enough to make up all of this mass, and ... 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 02:28: We have, of course, been trying to find evidence for black hole dark matter for some time. 02:37: If a study doesn’t find enough of black holes in that range, then that mass range is ruled out as a main contributor to dark matter. 02:50: Our hypothesis is that dark matter is made of black holes. 02:53: ... any gaps left - whether it’s still possible for black holes to explain dark matter. ... 03:47: ... near enough supernovae to give us enough black holes to make up all of dark matter. ... 03:57: Also, if dark matter is produced as stars die, you’d expect its influence to increase over time. 04:03: But we know that dark matter has been with us from the very beginning. 04:07: ... in the cosmic microwave background tell us that the gravity of dark matter was pulling matter together long before the first stars ever ... 04:18: So if dark matter is made of black holes then those black holes must have been with us from the beginning. 04:35: Now, we’ve talked about them before, but let’s dig much deeper into the question of whether primordial black holes could explain dark matter. 05:28: Because of this, to really falsify the primordial black hole as dark matter hypothesis, we need to rule out this entire mass range. 05:53: Dark matter can’t be made of these or anything close to because they tend to fall to the centers of their galaxies pretty quickly. 06:17: We can also rule out black holes a bit larger than this as dark matter. 06:20: ... dark matter to be made of black holes with masses around that of a larger asteroid ... 07:30: Probably no more than a few percent of the dark matter mass can be from these micro black holes. 07:40: At this point, gravitational lensing becomes the go-to method for dark matter hunters. 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 08:41: The very first MACHO microlensing events were detected, but there weren’t nearly enough to account for dark matter. 08:52: ... mass to 10 or so times the mass of the Sun as a main contributor to dark matter. ... 09:07: ... even if MACHOs aren’t all of dark matter, studies of the Magellanic Clouds and Andromeda have found enough ... 09:30: So far we’ve mostly ruled out black holes around the Sun’s mass or lower as an explanation for dark matter. 09:37: ... holes are tricky, because you need fewer of them to make up the mass of dark matter - which means they're less likely to spotted through microlensing ... 10:11: ... of the structures of dwarf galaxies tells us that no more than 4% of the dark matter could be black holes of tens to thousands of solar ... 10:37: We have some evidence ruling out most of the black hole mass spectrum as the main source of dark matter. 10:43: ... sensitive, and frankly it's unlikely that it just so happens that all dark matter is packed into the spots we haven’t properly looked at ... 10:57: ... dark matter probably isn’t black holes - but don’t be sad - that means dark matter ... 11:27: These so-called Planck relics are bad news as dark matter - because they’re essentially undetectable. 11:39: Whatever the case, dark matter is freaky stuff, fitting as the main material ingredient of our generally freaky space time. 01:25: ... real seems like a significant point in their favor as an explanation for dark matter - it’s more than we can say for any of the other dark matter particle ... 09:37: ... holes are tricky, because you need fewer of them to make up the mass of dark matter - which means they're less likely to spotted through microlensing ... 11:27: These so-called Planck relics are bad news as dark matter - because they’re essentially undetectable. 08:18: Broadly we call this breed of dark matter candidate “MACHOs” - massive, compact halo objects. 01:06: These hyper-dense holes in the fabric of spacetime seem to be great dark matter candidates - being so black and holey and all. 00:30: ... days most dark matter hunters are trying to hypothesize or detect exotic new particles to explain the ... 07:40: At this point, gravitational lensing becomes the go-to method for dark matter hunters. 05:28: Because of this, to really falsify the primordial black hole as dark matter hypothesis, we need to rule out this entire mass range. 02:19: We could get to the required dark matter mass with lots of massive black holes, or ludicrously many smaller black holes. 07:30: Probably no more than a few percent of the dark matter mass can be from these micro black holes. 01:25: ... for dark matter - it’s more than we can say for any of the other dark matter particle ... 09:07: ... even if MACHOs aren’t all of dark matter, studies of the Magellanic Clouds and Andromeda have found enough microlensing ... 00:44: ... of gravity - the general theory of relativity - that might explain dark matter’s influence without the need for actual ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... on the last two episodes that one on the dark universe the physics of dark matter particles and then the one where we explained how time must run slow in ...
	2021-01-26: Is Dark Matter Made of Particles? 00:00: By the time I finish this sentence, up to a billion billion dark matter particles may have streamed through your body like ghosts. 00:23: ... see the influence of dark matter in the orbits of stars and galaxies, in way light bends around galaxies ... 00:39: Even more disturbing is that there doesn’t even seem to be a candidate for dark matter in the known family of particles. 01:07: When we talk about the “dark sector” we typically mean a particle or family of particles that contribute to dark matter. 01:13: Now it’s possible that dark matter is not particles - it could be black holes or failed stars or even weirder so-called “compact objects”. 01:20: It might even be that what we perceive as dark matter is really a glitch in the laws we use to describe gravity. 02:58: The main requirement for a dark matter particle is that it doesn’t “speak electromagnetism”. 03:17: No, dark matter is both perfectly dark AND perfectly transparent. 03:27: ... Dark matter can’t have charge but it must have mass because the only thing we’ve ... 03:38: Dark matter “speaks gravity”. 03:45: ... can map where dark matter is found by how it affects the rotation of galaxies, and how it drives ... 03:58: These tell us something really important: dark matter is far more spread out - more diffuse - than almost all of the visible matter. 04:07: And that tells us a lot about any prospective dark matter particle. 04:10: For one thing, dark matter doesn’t tend to interact with itself - at least not very much. 04:15: If it did, then giant regions of dark matter would lose energy in those collisions and contract. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 04:25: But no - dark matter seems to stay puffed up in gigantic halos surrounding the much more concentrated clumps of visible matter. 04:34: In fact, galaxies are really just shiny dustings of stars, sprinkled deep in the gravitational wells of massive reservoirs of dark matter. 04:42: But the fact that dark matter forms those giant halos at all tells us something very important. 04:48: It gives dark matter a temperature. 04:51: More accurately, it tells us how far dark matter particles were able to travel in the early universe. 04:57: ... “free-streaming length” of dark matter is how far a dark matter particle could travel before interacting with ... 05:16: Now, based on how that structure did end up forming, it seems likely that dark matter was moving pretty slowly. 05:22: We refer to such dark matter as “cold”. 05:25: ... let’s review - if dark matter is a particle, it’s electrically neutral and doesn’t interact much with ... 05:35: For a long time people thought the neutrino might be dark matter - being neutral and the most abundant known particle in the universe. 05:52: ... but actually gets physicists very excited - because discovering a dark matter particle may be our best for finding a bigger, deeper theory than the ... 06:14: Dark matter hunters come in two breeds. 06:42: Actually, we don’t have to go too far beyond the standard model to find our first dark matter candidate. 06:47: Completely independently of our quest for dark matter, physicists have hypothesized a new type of neutrino - the so-called sterile neutrino. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 07:41: So to account for dark matter they’d need to exist in prodigious numbers … but according to pro-axion physicists, that may well be the case. 07:52: Explorations of the theoretical landscape have led physicists to multiple possibilities for dark matter particles. 08:01: We’ve also talked about supersymmetry, but not about how it could give us dark matter. 08:42: ... simplest kind of dark matter we get from supersymmetry is called a ‘neutralino.’ It’s a sort of ... 09:03: ... Model particles then they’d be stable and long lived- an almost perfect dark matter ... 09:15: ... are other dark matter candidates in different flavours of supersymmetry - all of them “LSPs” - ... 09:26: ... particles is eerily close to the mass expected for a certain type of dark matter - which some would say is a point in favor of ... 09:45: ... dark matter particles like the neutralino are examples of a general dark matter ... 09:59: It’s a description of what some physicists thought dark matter particles had to be like- which is to say, weakly interacting and massive. 10:17: We also covered weakly interacting - it helps dark matter halos stay puffed up. 10:22: ... it also turns out that the interaction strength of dark matter is extremely important - it may have governed how every interesting ... 11:36: ... would need to have in order to survive in sufficient numbers to give us dark matter. ... 12:17: Because dark matter is weakly-interacting, our light sector is probably more complex - probably. 05:35: For a long time people thought the neutrino might be dark matter - being neutral and the most abundant known particle in the universe. 09:26: ... particles is eerily close to the mass expected for a certain type of dark matter - which some would say is a point in favor of ... 06:42: Actually, we don’t have to go too far beyond the standard model to find our first dark matter candidate. 07:15: If sterile neutrinos exist AND are massive and slow-moving enough, they’re a great dark matter candidate. 09:15: ... are other dark matter candidates in different flavours of supersymmetry - all of them “LSPs” - for ... 04:10: For one thing, dark matter doesn’t tend to interact with itself - at least not very much. 04:42: But the fact that dark matter forms those giant halos at all tells us something very important. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 10:17: We also covered weakly interacting - it helps dark matter halos stay puffed up. 06:14: Dark matter hunters come in two breeds. 02:58: The main requirement for a dark matter particle is that it doesn’t “speak electromagnetism”. 04:07: And that tells us a lot about any prospective dark matter particle. 04:57: ... “free-streaming length” of dark matter is how far a dark matter particle could travel before interacting with something - typically another such ... 05:52: ... but actually gets physicists very excited - because discovering a dark matter particle may be our best for finding a bigger, deeper theory than the standard ... 09:03: ... Model particles then they’d be stable and long lived- an almost perfect dark matter particle. ... 09:45: ... dark matter particles like the neutralino are examples of a general dark matter particle type called the WIMP, or “weakly interacting massive ... 00:00: By the time I finish this sentence, up to a billion billion dark matter particles may have streamed through your body like ghosts. 04:51: More accurately, it tells us how far dark matter particles were able to travel in the early universe. 07:52: Explorations of the theoretical landscape have led physicists to multiple possibilities for dark matter particles. 09:45: ... dark matter particles like the neutralino are examples of a general dark matter particle type ... 09:59: It’s a description of what some physicists thought dark matter particles had to be like- which is to say, weakly interacting and massive. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people. 06:47: Completely independently of our quest for dark matter, physicists have hypothesized a new type of neutrino - the so-called sterile neutrino. 03:38: Dark matter “speaks gravity”. 04:21: They might collapse into dark matter galaxies or dark matter stars or dark matter people.
	2020-08-24: Can Future Colliders Break the Standard Model? 07:00: It doesn’t seem to give us a particle that could explain dark matter.
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... uh for just for example eric ferlindy comes up with an idea that maybe dark matter and gravity are in fact emergent properties of sort of the quantum ...
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 04:48: ... of the universe is incomplete. It doesn’t explain dark energy, dark matter, or this baryon asymmetry problem. So, if there exists some underlying ...
	2020-06-15: What Happens After the Universe Ends? 11:03: Penrose also says that CCC naturally gives you dark matter - but we’ll skip that for now.
	2020-06-08: Can Viruses Travel Between Planets? 13:58: ... law for gravity holds on the cosmic scales if we haven’t explained dark matter yet, which originated from the apparent failure of the inverse square ... 14:11: In other words, maybe the inverse square law breaks down on large scales, producing the illusion of dark matter. 14:32: Two issues with this idea: MONDS fails to get rid of the need for all dark matter. 14:44: ... we have other evidence of dark matter - for example in gravitational lensing, in the cosmic microwave ...
	2020-05-04: How We Know The Universe is Ancient 11:07: ... stuff there actually is. The mass of the universe - which is mostly in dark matter - can be found by adding up the gravitational effect in galaxies and in ...
	2020-04-22: Will Wormholes Allow Fast Interstellar Travel? 14:59: ... x-ray satellite. Leo also asks whether these bubbles might be caused by dark matter interactions with the black hole. I'm afraid I don't know of any theory ...
	2020-04-14: Was the Milky Way a Quasar? 02:19: ... were using the Fermi Gamma-ray Space Telescope to look for evidence of dark matter in the innermost regions of the Milky ... 02:33: ... astronomers believe that when dark matter particles crash into and annihilate each other, the result could be a ... 02:42: We have of course covered dark matter and dark energy in detail previously. 02:54: Dark matter has the property that it tends to spread out diffusely and evenly. 03:06: Gamma rays produced by dark matter annihilations should have similar structure. 02:33: ... astronomers believe that when dark matter particles crash into and annihilate each other, the result could be a fireworks ...
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 13:01: ... mostly about the hypothetical particle that might solve the mystery of dark matter - if we could just detect the ... 13:39: There were a couple of questions and comments on the discord about how axions could be dark matter - aren't they too fast moving? and too light? 14:19: Sure, each would be very light, but their could be enough of them to perfectly account for dark matter. 14:26: ... in the comments: if axions come from stars, would galaxies lose their dark matter and fly apart once the stars ... 14:45: If axions are dark matter then it would have to be the primordial axions - the ones formed in the big bang. 14:51: ... produced in stars now would be a tiny fraction of the mass we see in dark matter - in fact they'd be a tiny fraction of the mass we see in stars, which ... 13:01: ... mostly about the hypothetical particle that might solve the mystery of dark matter - if we could just detect the ... 13:39: There were a couple of questions and comments on the discord about how axions could be dark matter - aren't they too fast moving? and too light? 14:51: ... produced in stars now would be a tiny fraction of the mass we see in dark matter - in fact they'd be a tiny fraction of the mass we see in stars, which is ...
	2020-02-11: Are Axions Dark Matter? 00:51: ... exist, may explain a much more famous conundrum. The axion may explain dark matter. ... 11:08: ... there’s a good reason for the effort: axions may be ... dark matter. They have all the right properties - no direction interaction with ...
	2019-12-02: Is The Universe Finite? 01:38: ... large and geometrically flat, and is dominated by the influences of dark matter and a constant density of dark ... 06:41: See, gravitational lensing is caused by mass - both dark matter and atoms.
	2019-10-07: Black Hole Harmonics 09:53: ... doesn’t matter what fell in to make the black hole – atoms, photons, dark matter, monkeys – all that information should be lost, leaving only 3 ...
	2019-07-25: Deciphering The Vast Scale of the Universe 07:32: ... assembled into many vast filaments, flowing together on rivers of dark matter to form the cosmic web, of which Laniakea is just a ...
	2019-06-17: How Black Holes Kill Galaxies 01:35: ... itself depends on the total mass of the Galaxy including Dark Matter so why shouldn't a Galaxy and its Black Hole be closely connected A ... 02:54: ... on our understanding of Physics of the Universe especially the nature of Dark Matter and Dark Energy we expect 'Bottom up Galaxy formation' this is what we ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 14:46: ... comments from the last two videos - our episode on the galaxy without dark matter, and our coverage of the event horizon telescope's black hole ... 14:57: AspLode asks about the interaction between dark matter and black holes. 15:02: Can dark matter form a black hole? 15:04: ... assuming that dark matter is some sort of exotic particle - which is the going hypothesis - then ... 15:27: Occasional dark matter particles would be snared by black holes - and they would add to its mass just like regular matter. 15:35: But dark matter alone could never clump together densely enough to produce a black hole by itself. 15:02: Can dark matter form a black hole? 15:04: ... is the going hypothesis - then black holes would definitely attract dark matter gravitationally, and occationally eat the ... 15:27: Occasional dark matter particles would be snared by black holes - and they would add to its mass just like regular matter. 15:19: One of dark matter's definig qualities is that it doesn't clump together - it remains diffusely spread out through our galaxy.
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... been failing to detect dark matter for decades but finally the latest failure to detect Dark Matter may ...
	2019-03-20: Is Dark Energy Getting Stronger? 00:04: ... CDM Model and is built on the idea about the behavior of Dark Energy and Dark Matter. ... 00:29: Subtle clues are emerging that the accepted model for the nature of dark energy and dark matter may not be all that. 02:22: Those same textbooks talk about dark matter – an invisible stuff whose gravitational influence overwhelms all types of visible matter combined. 02:40: ... of study and calculation suggest that dark matter is a particle of some unknown type, cold, diffuse, and immune to ... 02:51: ... the textbooks, this type of cold dark matter sits alongside the cosmological constant as our best description of how ... 03:02: Constant dark energy, cold dark matter – or the Lambda-CDM model. 03:19: ... the starting conditions of the universe – the balance of dark energy, dark matter, and everything else at the earliest of times when the CMB was released ... 05:32: Perhaps the cosmological constant is not so constant, or dark matter is not so cold after all. 02:51: ... the textbooks, this type of cold dark matter sits alongside the cosmological constant as our best description of how the ...
	2019-02-20: Secrets of the Cosmic Microwave Background 01:47: ... painted a simplistic picture A quick review In the very beginning Dark matter flowed towards tiny regions of increased ... 07:42: ... us the total amount of energy It tells us the sum total of baryons, dark matter, and dark energy We'll see how useful that is when we look at the rest of ... 11:14: ... peaks which represent the smallest fluctuations These tell us about the dark matter Well more accurately they tell us about the relative amount of dark ... 12:34: ... just the amount of baryons and the higher peaks give you the amount of Dark Matter Combining this, we can separate the relative contents of all three ... 11:14: ... matter Well more accurately they tell us about the relative amount of dark matter compared to radiation, or light Now this is a bit too much of a rabbit hole for ... 12:34: ... because we get approximately the same numbers when we look at the dark matter content in modern galaxies and clusters and the dark energy based on measuring ... 01:47: ... painted a simplistic picture A quick review In the very beginning Dark matter flowed towards tiny regions of increased ... 11:14: ... You can actually figure out when the radiation epoch gave way to the Dark Matter-dominated Epoch That in turn tells you how much dark matter there is Spoiler: ...
	2019-02-07: Sound Waves from the Beginning of Time 03:16: Mixed in this soup of baryons and photons was dark matter. 03:21: ... fact, dark matter outweighs baryons by a factor of five, Which means it was, by far, the ... 03:31: But unlike baryons, dark matter does not interact with light at all. 03:35: Light exerts no pressure on dark matter. 03:38: Okay, so, the universe is filled with this hot ocean of baryons, photons, and dark matter. 04:19: In particular, the dark matter flowed inwards towards this density peak. 06:33: While all of this was happening, dark matter was doing its own thing. 06:37: Immune to the radiation pressure, the central dark matter overdensity had continued to grow It pulled on the expanding shell, and was pulled by it. 06:46: ... the expanding wave froze, both dark matter and baryons flowed together and consolidated the new structure. Once ... 09:27: ... form in the centers of those primordial density fluctuations, where the dark matter was the most ... 10:10: That's the clustering from the giant dark matter density peaks. 10:21: These are the galaxy pairs where one is at the center of the dark matter peak, and one is on the surrounding ring. 16:40: It can also be used to explain dark energy and dark matter. 10:10: That's the clustering from the giant dark matter density peaks. 04:19: In particular, the dark matter flowed inwards towards this density peak. 06:46: ... consolidated the new structure. Once more in the gravitational grip of dark matter, hydrogen and helium could begin the long work of collapsing into stars and ... 03:21: ... fact, dark matter outweighs baryons by a factor of five, Which means it was, by far, the dominant ... 06:37: Immune to the radiation pressure, the central dark matter overdensity had continued to grow It pulled on the expanding shell, and was pulled by it. 10:21: These are the galaxy pairs where one is at the center of the dark matter peak, and one is on the surrounding ring.
	2019-01-30: Perpetual Motion From Negative Mass? 00:59: And we also recently covered a very new use for negative mass: as “dark fluid”, a proposed explanation for both dark matter and dark energy.
	2019-01-24: The Crisis in Cosmology 11:53: Two: Dark matter particles behave differently to how we thought. 11:57: Perhaps dark matter interacts more strongly with matter and radiation,... 13:02: ...to investigate the mysterious physics of dark energy, dark matter,... 13:29: ...as a unifying explanation of both dark matter and dark energy. 14:03: ...the gravitational lensing measurements of dark matter... 14:06: ...will give the exact opposite results if dark matter is due to this negative mass fluid... 14:32: And yeah, those measures tell us that dark matter has positive mass I'd need to do the simulations, but I have a feeling... 14:44: ...if the effect of dark matter was due to this dark fluid. 17:46: He reveals to us that dark energy equals dark matter,... 11:57: Perhaps dark matter interacts more strongly with matter and radiation,... 11:53: Two: Dark matter particles behave differently to how we thought.
	2019-01-09: Are Dark Matter And Dark Energy The Same? 00:07: Dark energy AND dark matter? 00:22: ... at Oxford just published a paper suggesting that both dark energy and dark matter may result from the same ... 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 01:08: As with any new theory combining dark matter and dark energy, probably it helps to know what they are first. 01:18: So, dark matter: the galaxies are spinning too fast. 01:39: We call it dark matter, and try as we might we can’t find the presumably-exotic particle that constitutes it. 03:50: Jamie Farnes was looking for a way to get an anti-gravitational effect that explained both dark energy AND dark matter. 06:05: That’s a bizarre situation, but as I’ll explain in a moment it’ll give us our dark matter replacement. 06:11: In fact let’s start with dark matter because that’s a bit more straightforward. 10:31: Those supernova results suggest a universe that started expanding rapidly and then slowed down due to the gravity of matter – mostly dark matter. 11:47: ... positive energy density, when added to the energy of both regular and dark matter, are needed to explain this spatially flat ... 11:57: If you replace both dark energy and dark matter with negative-energy stuff, then the universe becomes negatively curved. 00:58: Farnes 2018, “A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified Lambda-CDM framework”. 06:05: That’s a bizarre situation, but as I’ll explain in a moment it’ll give us our dark matter replacement.
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... said Hoyle was afraid of pursuing fringe ideas even that new dark energy dark matter is a negative mass fluid thing reference to seem heavily and yeah we'll ...
	2018-10-10: Computing a Universe Simulation 05:55: ... you want to include photons, neutrinos, dark matter, et cetera, and not just atoms, you need to scale up the surface area by ...
	2018-09-12: How Much Information is in the Universe? 00:25: ... then there's all the stuff that isn't stars-- the dark matter, black holes, planets, and the particles, and radiation in between the ... 06:42: The situation with dark matter is unclear, so let's just round up to 10 to the power of 90 bits of information in particles in our universe. 10:03: Also ignore dark matter. 00:25: ... then there's all the stuff that isn't stars-- the dark matter, black holes, planets, and the particles, and radiation in between the stars ...
	2018-08-23: How Will the Universe End? 08:33: By the way, dark matter will probably also be long gone by now. 08:38: ... though we don't know exactly what it is, dark matter particles will likely either annihilate themselves as they collide with ...
	2018-07-04: Will A New Neutrino Change The Standard Model? 01:09: ... family since the Higgs boson, sterile neutrinos are a candidate for dark matter, and their existence would have had a huge influence on the expansion of ... 09:25: That's heavier than regular neutrinos but way too light to be a candidate for dark matter.
	2018-05-09: How Gaia Changed Astronomy Forever 06:59: This dynamical information will be a powerful tool in understanding the dark matter distribution of the galaxy. 07:17: It's been hypothesized that disruptions in these flows are due to clumps of dark matter, so-called sub halos. 07:25: The nature of sub halos, and other details of dark matter's distribution, could help us figure out what dark matter really is. 06:59: This dynamical information will be a powerful tool in understanding the dark matter distribution of the galaxy. 07:17: It's been hypothesized that disruptions in these flows are due to clumps of dark matter, so-called sub halos. 07:25: The nature of sub halos, and other details of dark matter's distribution, could help us figure out what dark matter really is.
	2018-05-02: The Star at the End of Time 09:24: Joshua Hillerup asks whether dynamical friction leads to less dark matter near the centers of galaxies since dark matter's not very dense. 09:34: Yeah, dark matter is expected to be more evenly spread through the galaxy than things like stars and black holes. 09:41: ... Dark matter exists in a puffy sphere some 200,000 light years in radius surrounding ... 09:24: Joshua Hillerup asks whether dynamical friction leads to less dark matter near the centers of galaxies since dark matter's not very dense.
	2018-03-28: The Andromeda-Milky Way Collision 05:06: They used simulations of the gravitational interactions of millions of particles representing groups of stars and dark matter. 10:00: Patrick Hogan points out that it's more accurate not to think about dark matter as a thing. 10:17: That's very fair, Patrick, but I would say that the evidence is converging on dark matter being some sort of particle or at least a stuff. 10:25: ... one thing, there's the consistency of the dark matter mass measurements of galaxies and galaxy clusters from gravitational ... 10:33: ... also the fact that dark matter appears to distribute itself differently to regular matter but still ... 10:43: ... the case of the result we discussed, the entire hypothesis that dark matter was responsible for the cooling of the early universe relies on it being ... 10:33: ... also the fact that dark matter appears to distribute itself differently to regular matter but still comes ... 10:25: ... one thing, there's the consistency of the dark matter mass measurements of galaxies and galaxy clusters from gravitational lensing ...
	2018-03-21: Scientists Have Detected the First Stars 00:00: [MUSIC PLAYING] What do the first stars in the universe, dark matter, and superior siege engines have in common? 00:43: The same result also hints at brand new physics that may help us explain the nature of dark matter. 05:15: The only thing colder than this ambient hydrogen at the time, was dark matter. 05:20: So maybe, the hydrogen lost some of its heat to dark matter. 05:24: Yet, in order for that to happen, hydrogen would actually need to interact with the dark matter, and that's the whole thing about dark matter.
	2018-01-31: Kronos: Devourer Of Worlds 01:49: ... black holes and neutron stars, as well as the distribution of gas and dark matter. ...
	2017-11-02: The Vacuum Catastrophe 09:33: ... for a time, it was thought that neutrinos might actually be dark matter until it was realized they just don't contain enough mass, nor are they ... 09:42: They're too hot to pull into the deep dark matter wells that we see in galaxy clusters. 09:54: However, usually the dark sector term is used to describe the actual sources of dark matter and dark energy. 09:42: They're too hot to pull into the deep dark matter wells that we see in galaxy clusters.
	2017-10-25: The Missing Mass Mystery 00:49: However, we've known for some time that around 95% of the energy content of the universe is in dark matter and dark energy. 01:39: First, a quick refresher on dark matter and dark energy. 01:45: Dark matter is believed to be an invisible stuff that interacts only through gravity. 02:08: Now where dark matter pools, dark energy pushes. 04:07: And by analyzing these fluctuations, we can figure out the relative abundance of baryons to dark matter. 04:43: Those large blobs are driven by dark matter, which doesn't interact with light, so it can't produce density oscillations. 04:51: ... CMB power spectrum, we can find the relative amount of baryonic versus dark matter. ... 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them. 09:10: ... pairs of nearby massive galaxies, the type typically found in giant dark matter ... 10:10: ... our predictions for the relative mass in baryons versus dark matter was so wrong, then it would mean the our understanding of the physics of ... 10:22: ... out in the vastness of intergalactic space, still flowing with rivers of dark matter into the galaxy ... 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them. 09:10: ... pairs of nearby massive galaxies, the type typically found in giant dark matter halos. ... 02:08: Now where dark matter pools, dark energy pushes.
	2017-08-10: The One-Electron Universe 12:24: M. Paulson poked fun at astronomers for using "dark" to describe anything they don't understand-- dark matter, dark energy, dark flow.
	2017-08-02: Dark Flow 08:58: ... bubble of observable universe with more galaxies, more clusters, more dark matter? ...
	2017-06-07: Supervoids vs Colliding Universes! 07:47: It's the same notion that people have tried to use to explain dark matter. 08:01: However, modified gravity is on shaky ground because, well, dark matter is looking more and more like real stuff, not incorrect gravity.
	2017-02-15: Telescopes of Tomorrow 02:55: Webb will help us learn whether stars form galaxies or galaxies form stars and the role of dark matter in the whole process.
	2016-11-16: Strange Stars 12:57: ... entropic gravity, and the possibility that it might explain both dark matter and dark ...
	2016-11-09: Did Dark Energy Just Disappear? 06:35: ... is just the gravitational effect of regular energy, and that's mostly dark matter, but also stars, planets, gas, radiation, et ... 08:38: Counting galaxies and weighing dark matter tells us that Omega-m is probably around 0.3, but it's at least around 0.2.
	2016-10-12: Black Holes from the Dawn of Time 04:43: Could primordial black holes be dark matter? 06:07: These arguments let us rule out all but a very narrow set of mass ranges for primordial black holes as an explanation for dark matter. 07:07: ... that PBHs are actually very rare, and that they're certainly not dark matter. ... 07:24: ... that have already evaporated due to Hawking radiation definitely are not dark matter, and that rules out any PBHs lighter than about a billion ...
	2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer 03:25: ... could be everywhere and we wouldn't know it, like ninjas and like dark matter. ... 03:40: Not that dark matter is ninjas. 03:46: I mean that this new particle may have something to do with dark matter.
	2016-06-15: The Strange Universe of Gravitational Lensing 04:31: And we've confirmed that the vast majority of mass in this universe is in the form of dark matter. 07:06: We see that they encircle the vast strands and nexuses of dark matter that form the cosmic web, allowing us to understand its structure.
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 03:09: The broad family of possibilities include one-- dark matter. 03:14: There are theoretical ideas of particles that could cause a bump at this energy, and would also make pretty decent dark matter candidates.
	2016-05-11: The Cosmic Conspiracy of Dark Energy Challenge Question 01:15: And by regular, I also mean dark matter, which is actually most of that 30%.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 10:15: But if the density of dark matter varies with time, then there are a range of possibilities.
	2016-04-27: What Does Dark Energy Really Do? 00:03: The idea that the fate of our universe is governed by forces that we can see was abandoned with the discovery of dark matter. 11:23: These surveys don't measure dark matter content of all of their galaxy clusters. 11:28: But again, we've weighed up the dark matter in enough of them to be able to extrapolate. 11:23: These surveys don't measure dark matter content of all of their galaxy clusters.
	2016-04-20: Why the Universe Needs Dark Energy 10:20: Mychelly Goulart would like to know whether the density we use in the Friedmann equation includes dark matter. 10:28: ... we calculate when we figured out the fate of the universe does include dark matter, which we can measure by its gravitational effect in several independent ... 10:38: Even with dark matter, the universe is just not dense enough to recollapse.
	2016-04-13: Will the Universe Expand Forever? 07:36: Astronomers worked for decades to weigh up the galaxies across vast swaths of the universe, including their dark matter.
	2016-03-23: How Cosmic Inflation Flattened the Universe 10:15: ... Schneider asks, "Why does dark matter in a galaxy seem to form a sphere?" Well, this is because dark matter ... 10:47: Dark matter doesn't sweep itself. 10:54: So the orbits of any bit of dark matter can be in any orientation or direction. 10:15: ... dark matter in a galaxy seem to form a sphere?" Well, this is because dark matter doesn't really interact with itself except ... 10:47: Dark matter doesn't sweep itself.
	2015-09-30: What Happens At The Edge Of The Universe? 08:18: The galaxy orbits give us a mass for the dark matter in the clusters and the lensing gives us a mass consistent with this. 08:25: Shadowmax889 asks why stars and planets aren't filled with dark matter? 08:31: Dark matter is cold and clumpy, which means it can bunch together to form galaxies. 09:03: Dark matter doesn't do that. 09:16: ... informs us that upon winning a Nobel Prize for discovering dark matter particles, he or she would spend all of the prize money on Phoenix ... 09:03: Dark matter doesn't do that. 09:16: ... informs us that upon winning a Nobel Prize for discovering dark matter particles, he or she would spend all of the prize money on Phoenix ...
	2015-09-23: Does Dark Matter BREAK Physics? 00:00: [MUSIC PLAYING] Dark matter literally binds the galaxy together. 00:07: Nobody knows what dark matter is. 00:45: This is the mystery of dark matter. 00:47: ... before we get into figuring out exactly what dark matter is or isn't, I want to give you completely independent evidence for its ... 01:29: So knowing this, let's summarize the actual possibilities for dark matter. 01:41: Two, not so great, dark matter is a type of particle that's beyond our current understanding of particle physics. 02:12: If dark matter exists in this model, its mass probably needs to come from protons and neutrons. 02:19: ... this is dark matter, the galaxy would need to be swarming with baryonic things as massive as ... 03:03: But not nearly enough to account for all of the dark matter. 03:43: Could it be that what we see as dark matter just comes from gravity behaving differently on truly gigantic scales? 03:55: ... to distance instead of distance squared, and then you don't even need dark matter. ... 04:21: Any replacement theory has to reproduce all, and I mean all, of the verified predictions of Einstein's theory and be able to explain dark matter. 04:39: They either need some serious fine-tuning or you have to add back in some actual dark matter particles, which kind of defeats the purpose. 05:02: So if dark matter really comes from weirdly behaving gravity, then the cluster's gravity should stay concentrated on the gas. 05:08: ... if dark matter is an unseen particle, and it's the type of particle we think it might ... 05:25: And we see that in the Bullet Cluster, the dark matter is with the stars. 05:35: Dark matter exists and it represents, if not broken, at least incomplete particle physics. 05:45: It has to be pretty slow moving, or cold, because we know that dark matter clumps together gravitationally to build galaxies and clusters. 06:13: Dark matter, as well as binding the galaxy together, is also the main force in forming galaxies in the first place. 06:20: No dark matter, no galaxies. 06:23: And even then, galaxies could only have formed if dark matter particles are cold, massive, and weakly interacting. 06:30: Weakly interacting massive particles, WIMPs, actually refers to a specific and popular contender for dark matter. 06:55: Some of them fit the bill for dark matter. 07:05: Some of which may actually exist and some of them may be dark matter. 07:14: ... to catch the fall-out between the unthinkably rare collisions between a dark matter particle and an atomic ... 07:22: We also watch the heavens for the equally elusive gamma radiation produced when dark matter particles annihilate each other out in space. 07:36: ... I'll report any previously undiscovered dark matter particles on the next episode of "SpaceTime." Last time on "SpaceTime," ... 05:45: It has to be pretty slow moving, or cold, because we know that dark matter clumps together gravitationally to build galaxies and clusters. 02:12: If dark matter exists in this model, its mass probably needs to come from protons and neutrons. 05:35: Dark matter exists and it represents, if not broken, at least incomplete particle physics. 00:00: [MUSIC PLAYING] Dark matter literally binds the galaxy together. 07:14: ... to catch the fall-out between the unthinkably rare collisions between a dark matter particle and an atomic ... 04:39: They either need some serious fine-tuning or you have to add back in some actual dark matter particles, which kind of defeats the purpose. 06:23: And even then, galaxies could only have formed if dark matter particles are cold, massive, and weakly interacting. 07:22: We also watch the heavens for the equally elusive gamma radiation produced when dark matter particles annihilate each other out in space. 07:36: ... I'll report any previously undiscovered dark matter particles on the next episode of "SpaceTime." Last time on "SpaceTime," we talked ...

72 result(s) shown.

Help · About · Index