Can He-4 atoms create black holes?

Question

Suppose that in the intergalactic space far from any significant gravitational attractors there is a relatively small concentration of He-4 atoms. Due to gravitational attraction fermions in this case would form a sphere (gas planet), but as bosons He-4 atoms aren't affected by exclusion prinicple, so what's holding them back from collapsing into singularity?

Answer 1

Helium nuclei behave like bosons only in phenomena where their integrity is preserved and they can be assumed as point-like particles.

When you compress them a lot this is not the case any more. Single protons and neutrons will start to interact with each other and they are fermions. You have no chance to condensate them in a black hole, indeed what you get are triple-alpha processes in which helium is fused to $^{12}$C.

Answer 2

If it is a planetary size mass, then thermal pressure from the kinetic energy of the atoms would prevent collapse.

For larger masses, helium fusion would create radiation pressure to stop the collapse.

Also, helium plasma would contain free electrons which would cause electron degenarcy pressure. Red giants of less than 2 solar masses initially have helium cores which are sustained by electron degeneracy pressure, until temperature is hot enough for helium fusion to start.