Reheating a multi-throat universe by brane motion

TL;DR

This paper introduces a reheating mechanism in multi-throat warped extra dimension models where brane motion after inflation excites Standard Model fields, effectively reheating the universe.

Contribution

It proposes a novel reheating process involving brane motion in multi-throat scenarios, linking brane dynamics to Standard Model field excitation.

Findings

Brane motion can reheat the universe after inflation.

The SM brane moves towards the throat tip post-inflation.

Modulus decay into SM fields is efficient due to local string scale.

Abstract

We propose a mechanism of reheating after inflation in multi-throat scenarios of warped extra dimensions. Validity of an effective field theory on the standard model (SM) brane requires that the position of the SM brane during inflation be different from the position after inflation. The latter is supposed to be near the tip of the SM throat but the former is not. After inflation, when the Hubble expansion rate becomes sufficiently low, the SM brane starts moving towards the tip and eventually oscillates. The SM fields are excited by the brane motion and the universe is reheated. Since interaction between the brane position modulus and the SM fields is suppressed only by the local string scale, the modulus effectively decays into the SM fields.