Darkflation -- one scalar to rule them all?

TL;DR

This paper explores a minimal extension of the Standard Model with a scalar singlet to unify explanations for inflation and dark matter, analyzing the effective gravitational action during inflation.

Contribution

It derives an effective gravitational action incorporating a scalar dark matter candidate nonminimally coupled to gravity, linking Standard Model parameters to inflationary dynamics.

Findings

Effective action expressed solely in terms of gravity after integrating out matter fields

Explicit calculation of higher-order curvature terms and their dependence on Standard Model couplings

Discussion of the implications for inflationary models and dark matter physics

Abstract

The problem of explaining both inflationary and dark matter physics in the framework of a minimal extension of the Standard Model was investigated. To this end, the Standard Model completed by a real scalar singlet playing a role of the dark matter candidate has been considered. We assumed both the dark matter field and the Higgs doublet to be nonminimally coupled to gravity. Using quantum field theory in curved spacetime we derived an effective action for the inflationary period and analyzed its consequences. In this approach, after integrating out both dark matter and Standard Model sectors we obtained the effective action expressed purely in terms of the gravitational field. We paid special attention to determination, by explicit calculations, of the form of coefficients controlling the higher-order in curvature gravitational terms. Their connection to the Standard Model coupling constants has been discussed.