Gravitational particle creation in a stiff matter dominated universe

: Lankinen J, Vilja I

Publisher: IOP PUBLISHING LTD

: BRISTOL

: 2017

: Journal of Cosmology and Astroparticle Physics

: JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

: J COSMOL ASTROPART P

: ARTN 025

: 8

: 12

: 1475-7516

DOI: https://doi.org/10.1088/1475-7516/2017/08/025

: 10.1088/1475-7516/2017/08/025

A scenario for gravitational particle creation in a stiff matter dominated flat Friedmann-Robertson-Walker universe is presented. The primary creation of scalar particles is calculated using quantum field theory in curved spacetime and it is found to be strongly dependent on the scalar mass and the expansion parameter of the universe. The particle creation is most effective for a very massive scalar field and large expansion parameter. We demonstrate the phenomenon by applying it to cosmological toy model scenario, where secondary particles are created by the scalar field decay.