Thermal statistics in the hot universe

[Accidently]

We know that the particles in the hot universe obey Fermi/Bose statistics, but when we calculate the scalar dynamics i.e. in inflation or dark energy... and maybe also something else, it seems we don't take into account the statistics and just use one scalar field to calculate all these things... Should it be a distribution of field?

 

[Chalnoth]

Fermi/Bose statistics are useful for thermal distributions. Inflation/dark energy simply aren't thermal phenomena. I've never seen anybody try to examine what a thermal distribution of such fields would look like, but my suspicion is that it wouldn't produce an accelerated expansion.