>>11853961For the most part, antimatter is the charge conjugate of regular matter (electron->positron, quark->antiquark). Don't worry about neutrinos because they're pretty fucked and we still don't know if antineutrinos and neutrinos are the same thing.
Antimatter and regular matter do really annihilate. Without delving too deeply, the process of matter/antimatter converting into photons is an allowed process (as is the reverse process), as it doesn't violate any physical conservation laws (conservation of charge, lepton number, baryon number, etc.). Electrons don't annihilate because they would violate the total amount of charge. Electrons and protons don't annihilate because they would violate lepton/baryon number. So only particles and their own antiparticles can annihilate to make photons.
>why is there more regular matter than antimatter in the universe?if you figure this out then you'll get a nobel prize. Currently trying to study this in my lab.
However, we know certain conditions must have held in the early universe in order for there to be this imbalance. There must have been a physical process that is charge-parity violating, meaning that these quantities (charge and parity) are not conserved through the process. We know of processes now that exist that violate this (neutral kaon decay does, for example), however the CP violation in the weak force is not nearly enough to account for the preference of matter over antimatter. There also must have been a process that didn't conserve baryon and lepton number, which could potentially be explained by sphalerons, although this explanation is incomplete because if this were true we would observe a completely different mass for the higgs.
Basically the standard model is fucked, and we don't even know where to look. There are a lot of theories that propose baryogenesis mechanisms, but they're quite hard to test.
