Probing Bose-enhanced Inflaton Decay with Gravitational Waves

TL;DR

This paper explores how Bose enhancement during inflaton decay can significantly boost gravitational wave production, leading to potentially observable stochastic backgrounds in the early universe.

Contribution

It introduces a new mechanism where a transient bosonic condensate enhances inflaton decay and gravitational wave signals beyond standard models.

Findings

Bose enhancement can dramatically increase inflaton decay efficiency.

Graviton production is significantly amplified by Bose effects.

Resulting gravitational-wave background may be detectable at low frequencies.

Abstract

We investigate cosmic reheating dynamics in the presence of a transient condensate formed by bosonic decay products of the inflaton. We show that the emergence of such a condensate and the corresponding Bose enhancement can dramatically increase the efficiency of inflaton decay, giving rise to qualitatively new reheating dynamics beyond the standard perturbative picture. As a consequence, graviton production from inflaton decay processes is significantly amplified by Bose enhancement effects, leading to a stochastic gravitational-wave background with a potentially observable amplitude, even in the low-frequency regime.