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  • dark matter is Cem cosmically strange stuff.

  • We can't see it, but it appears to outnumber all the stuff we can see all the stars and planets and random dust floating around by five toe one.

  • We only know or think.

  • We know it's there.

  • Because of the gravitational effect it has on.

  • Astronomers have spent decades trying to figure out what kind of strange stuff this dark matter could be made of.

  • One candidate is a bunch of regular matter.

  • Our equipment just isn't sensitive enough to detect, so the hunt also includes objects that are a little more exotic.

  • A handful of papers published within the past couple weeks dive into that hunt and show that it's far from over.

  • One of these candidates for Dark Matter is a group of black holes that formed long before the first stars ever shown they're called primordial Black holes, or PPH is, but there's not much actual evidence for them.

  • Yet there's still hypothetical the black holes we typically think of form after a really massive star goes supernova, but that doesn't have to be the only way.

  • It's been theories that not long after the Big Bang, small, random pockets of space just happened, have enough matter stuffed into them that they collapsed into black holes because they didn't start out from stars.

  • They could come in an extreme range of masses from fractions of a gram up too many, many times that of a star.

  • And that also means that, unlike buckles that started a stars, they're not likely to be surrounded by large spots of gas and dust, which would make them really tough to spot.

  • Some scientists, including Stephen Hawking, have suggested that these so far undetected black holes could make up at least some of the universe's dark matter.

  • Previous research had already found that they can't account for all dark matter, though.

  • So new Research out of Japan, published this week in the journal Nature Astronomy, set out to determine how abundant they might be To find these black holes, the team searched galactic halos.

  • That's the region beyond the disc, which it doesn't have nearly as many stars, gas and dust and is where astronomers suspect primordial black holes could invisibly hang out.

  • When a star passes between us and dark matter, it's like it's bent and magnified, so the hunt for P B H is the team monitor.

  • The change in brightness of over 10 million stars in the outer fringes of the Andromeda Galaxy and the Milky Way, after controlling for everything they could think of, that would cause a dip in brightness, including one unwelcome asteroid.

  • There was only one possible event that might be attributed to a p B h.

  • Annoyingly, even that one could just be a variable star that dips and brightness naturally, but they couldn't be sure.

  • But running with the assumption that they were able to observe a single potential PB H, the team was able to place an upper limit on just how common these things could possibly beat, at least in the range of masses they looked for.

  • If PB H is made up all dark matter, they would have expected to see about 1000 brightness steps over the course of their experiments.

  • Seeing only one, they say, it means that those PVH is could only account for a small fraction of dark matter, maybe 0.1% rather than black holes.

  • Other teams are working to find an incredibly tiny hypothetical particle called the accident.

  • Accents, if they exist, are fundamental particles.

  • That means that, like electrons, they're not made up of any constituent particles.

  • And like neutrinos, they have almost no mass and don't interact with ordinary matter very often and even weirder, they can actually bend the rules.

  • We expect electricity and magnetism to play by at least buy a teeny tiny amount.

  • Because of that, a team based out of M.

  • I T designed a laboratory experiment to try and detect these changes.

  • They call it average Cadavra, which might have been appropriate if they could have pulled dark matter out of it or if it had been shaped like a top hat.

  • But instead, it's a donut shaped magnet roughly the size of a basketball inside an insulated refrigerator.

  • Under the standard laws of electromagnetism, there's no magnetic field in the donut hole, but if an axiom is there, there should be.

  • It would be a soup Purdue per week, so roughly a trillion times weaker than the Earth's magnetic field.

  • So the team had to design their experiment to block out everything that could drown out that signal from the local radio stations toe L E.

  • D's on nearby electron ICS, and they had to keep the magnet as cold as possible just above absolute zero.

  • After running the experiment for a month, they were unable to detect evidence of acciones, at least none within their target mass range around a quintillion the size of a proton, so that either means they don't exist or their influence on electromagnetism isn't a strongest predicted.

  • But this experiment was on Lee a prototype, so a larger and better shielded one will be able to hunt for smaller Acciones.

  • They just haven't built it yet, but we don't necessarily have to build contraptions to find accidents.

  • We can try to find them in space on an astronomical scale.

  • A large number of acciones together could basically act as its own field.

  • Think of it like a cosmic all pit made of incomprehensibly tiny floating balls.

  • Stuff passing through would theoretically interact with these acciones.

  • At least a little, especially light, otherwise known as electromagnetic waves, and passing through the field would affect its polarisation or the angle of the light waves, and that is something we could potentially observe.

  • So when another recent paper published in the Journal of Cosmology and Astro Particle Physics, one team based in Russia went hunting for that polarization.

  • They looked at objects called active galactic nuclei, which are dense galactic centers that spew up tons of polarized electromagnetic radiation.

  • Specifically, they were looking to see if the polarization of the light coming from their targets changed over time and all in the same way.

  • So if they observe the predicted changes, that would mean that the light from all the different active galactic nuclei was being affected by an external field made up of a very large number of very light acciones.

  • But they didn't see that they, too, were unable to conclude whether or not Acciones exist, at least for their studied mass range, which, incidentally, was way smaller than the one probed by Abacha.

  • Tabara.

  • All of this work helps to place limits on what mass is dark matter particles can have or what they can even be.

  • It might be primordial black holes as massive as the earth, and it might be his teeny tiny as the smallest subatomic particles in existence or something else entirely.

  • Our technology just hasn't cut up with our curiosity yet it just means that the hunt for dark matter is still on and I can promise you that when scientists figure it out, you'll hear about it here.

  • Thanks for watching this episode of seditious based news.

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  • And no, I promised.

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dark matter is Cem cosmically strange stuff.

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