Reheating from Tachyon Condensation

TL;DR

This paper proposes a reheating mechanism after D-brane driven inflation via tachyon condensation, which can efficiently produce a hot universe if certain conditions on brane configuration and tachyon dynamics are met.

Contribution

It introduces a novel reheating process involving tachyon condensates coupling to massless fields, applicable when branes annihilate into a standard model brane.

Findings

Reheating efficiency increases with larger brane codimension.

Large derivatives of the tachyon background enhance reheating.

The mechanism can overcome cold dark tachyon matter dominance.

Abstract

We argue that it may be possible to reheat the universe after inflation driven by D-brane annihilation, due to the coupling of massless fields to the time-dependent tachyon condensate which describes the annihilation process. This mechanism can work if the original branes annihilate to a stable brane containing the standard model. Given reasonable assumptions about the shape of the tachyon background configuration and the size of the relevant extra dimension, the reheating can be efficient enough to overcome the problem of the universe being perpetually dominated by cold dark tachyon matter. In particular, reheating is most efficient when the final brane codimension is large, and when the derivatives of the tachyon background are large.