Antimatter Galaxies - do they exist?

It sounds absurd. Entire galaxies made of antimatter, in a universe of matter. That doesn’t stop us scientists wondering: is it possible?

Following logic, antimatter galaxies shouldn’t exist. Antimatter and matter react heavily with one another in such a manner that nothing except gamma rays is left (annihilation).

So, what circumstances would need to exist for our antimatter galaxies?

1. There would need to be processes that allow matter particles made of quarks to change.

2. There would need to be a larger amount of matter than antimatter.

This would grossly go against C-symmetry. The term C-symmetry is an abbreviation of the phrase "charge conjugation symmetry „and is used in discussions of the symmetry of physical laws under charge-conjugation. Charge conjugation is a transformation that switches all particles with their corresponding antiparticles, thus changing the sign of all charges: not only electric charge but also the charges relevant to other forces.

3. The process would need to take place in a thermal imbalance.

This does go against the laws of physics as we know and understand them, but let’s go over a possible route to existence. First, a larger mass of anti-matter gathers. This cloud the collapses in on itself due to its own gravity. Because of a rotary motion, a disc-like object forms. More anti-stars pop into existence. Antimatter galaxies fuse with other antimatter galaxies to give us a big antimatter galaxy.

The antimatter in these galaxies would have to have been generated during the big bang. Then it would have distanced itself from matter in an extreme vacuum. This means there would be border areas between them. The gamma radiation from those areas would be detectable on earth.

As already mentioned/hinted at there are problems with this theory.

· Matter and Antimatter would have to come in at some point resulting in a large amount of gamma rays.

· There’s never been a discovery of an anti-star.

· Discovery would be difficult as you can’t tell the difference between matter and antimatter through a telescope.