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Anti-matter is very rare with normal matter, so we don’t see it running out. But if dark matter and dark anti-matter are both just as common then you could see
by jeremyjh 3y ago
Anti-matter is very rare with normal matter, so we don’t see it running out. But if dark matter and dark anti-matter are both just as common then you could see it play out as they suggest.
- pfdietz 3y agoSome models of dark matter have the particles being their own antiparticles.
- JumpCrisscross 3y agoIs it just charge that causes particles to have an antiparticle?
- pfdietz 3y agoNo. Neutrons and antineutrons are different particles, for example.
- lanna 3y agoNeutrons don't have charge, but their quarks do. Antineutrons have quarks with reversed charge. Just like a neutral atom can have a neutral antiatom.
- addaon 3y agoIf you prefer, then, neutrinos are neutral but have an anti-particle (although it's still possible that neutrinos are Majorana particles, in which case they're their own anti-particle).
- pantulis 3y agoIf that was the case, given the abundance of DM, wouldn't we be detecting lots of energy due to their own annihilation?
- analog31 3y agoOne process could be that the radiation is absorbed within the ball of gas, leaving us to see only what's being radiated by the outer surface of the ball. Likewise the light that we get from the sun is produced by a thin shell near its surface.
- pfdietz 3y agoThat depends on the number density and annihilation cross section. There has been a gamma ray excess from around the galactic core that's been puzzling for a number of years; one explanation was annihilation of dark matter, although other more mundane explanations (like emissions from a population of neutron stars) I think are preferred now.
- mkl 3y agoIncluding the one used in the article: "If the DM particles are their own antiparticles, then their annihilation provides a heat source that stops the collapse of the clouds and in fact produces a different type of star, a Dark Star, in thermal and hydrostatic equilibrium."
- denton-scratch 3y agoBut then there wouldn't be any dark matter, and we wouldn't be arguing about halos.