Gravitational production of nearly thermal fermionic dark matter

  title={Gravitational production of nearly thermal fermionic dark matter},
  author={Nathan Herring and Daniel Boyanovsky},
  journal={Physical Review D},
We consider the cosmological production of fermionic dark matter during inflation and a post-inflationary radiation dominated era. This fermion \emph{only interacts gravitationally}, has a mass $m$ much smaller than the Hubble scale during inflation (but is otherwise arbitrary) and is in its Bunch-Davies vacuum state during inflation. We focus on superhorizon modes at the end of inflation, and assume instantaneous reheating. We obtain the full energy momentum tensor discussing its… 

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