Thermal effects on slow-roll dynamics

TL;DR

This paper explores how thermal effects influence the slow-roll inflationary dynamics by analyzing quantum field interactions out of equilibrium, revealing that thermal interactions can hasten the end of inflation.

Contribution

It introduces a first-principles approach using Schwinger-Dyson equations to study thermal effects on slow-roll inflation with a ^2^2 interaction.

Findings

Interactions cause an earlier end to slow-roll.

Post-slow-roll evolution depends on heatbath details.

Thermal effects significantly impact inflation dynamics.

Abstract

A description of the transition from the inflationary epoch to radiation domination requires the understanding of quantum fields out of thermal equilibrium, particle creation and thermalisation. This can be studied from first principles by solving a set of truncated real-time Schwinger-Dyson equations, written in terms of the mean field (inflaton) and the field propagators, derived from the two-particle irreducible effective action. We investigate some aspects of this problem by considering the dynamics of a slow-rolling mean field coupled to a second quantum field, using a \phi^2\chi^2 interaction. We focus on thermal effects. It is found that interactions lead to an earlier end of slow-roll and that the evolution afterwards depends on details of the heatbath.