Primordial dark matter from curvature induced symmetry breaking

Abstract

We demonstrate that adiabatic dark matter can be generated by gravity induced symmetry breaking during inflation. We study a $Z_2$ symmetric scalar singlet that couples to other fields only through gravity and for which the symmetry is broken by the spacetime curvature during inflation when the non-minimal coupling $\xi$ is negative. We find that the symmetry breaking leads to the formation of adiabatic dark matter with the observed abundance for the singlet mass $m\sim \mathrm{MeV}$ and $|\xi |\sim 1$.

Comments: 13 pages, 5 figures. v2; minor edits, published in JCAP