When the universe was very young, in its hydrogen helium phase, was any dark matter present then?

If not did stars create it?

Dark matter is most likely to be a sub atomic particle.

Neutrinos, sub atomic particles are emitted from stars as are photons.

I’m wondering if dark matter particles are emitted from stars as well.

> When the universe was very young, in its hydrogen helium phase, was any dark matter present then?

Yes.

If not did stars create it?

Dark matter is most likely to be a sub atomic particle.

Neutrinos, sub atomic particles are emitted from stars as are photons.

> I’m wondering if dark matter particles are emitted from stars as well.

Good question, because it depends on which type of subatomic particle makes up dark matter.

If dark matter is supersymmetric matter then no. They are not emitted by stars.

If dark matter is axions then yes. They are emitted by stars.