Ekpyrotic Reheating and Fate of Inflaton

TL;DR

This paper demonstrates that perturbative reheating can achieve high temperatures even with minimal inflaton decay if the inflaton potential turns negative post-inflation, and explores the inflaton's potential role as dark matter.

Contribution

It introduces a model where a negative inflaton potential after inflation enables effective reheating and investigates the inflaton's potential to become dark matter.

Findings

High reheating temperatures are achievable with small decay rates.

The inflaton can serve as a dark matter candidate.

Dependence of outcomes on inflaton mass and coupling to matter.

Abstract

It is shown that perturbative reheating can reach a sufficiently high temperature with small or negligible inflaton decay rate provided that the inflaton potential becomes negative after inflation. In our model, inflaton and dark energy field are two independent scalar fields, and, depending on the mass of the inflaton and its coupling to matter fields, there is a possibility that the remaining inflaton after reheating can become a dark matter candidate.