Dark matter(and the solution to the anti-matter cosmology problem) may have been

Physicists Have Finally Seen Traces of a Long-Sought Particle. Here's Why That's a Big Deal.

The axions they've disocvered are a kind of quasi-particle that exits in special conditions; but, I recall reading an article in Quanta magazine(which I don't feel like digging out) where some physicist found that dark matter could be a kind of field in space. This could lend support to that theory.

https://www.livescience.com/axion-found-in-weyl-semimetal.html