The Secret Higgstory of the Highest Temperature during Reheating

TL;DR

This paper investigates how the Standard Model Higgs condensate influences the reheating process after inflation, leading to higher primordial temperatures and affecting the formation of relics and symmetry restoration.

Contribution

It demonstrates that the Higgs condensate decays non-perturbatively during reheating, significantly increasing the temperature of the primordial plasma and impacting cosmological relic formation.

Findings

Higgs condensate heats the plasma to higher temperatures than inflaton decay alone.

The hot plasma affects thermalization and relic formation.

Implications for dark matter, isocurvature fluctuations, and symmetry restoration.

Abstract

We study the role of the Standard Model Higgs condensate, formed during cosmological inflation, in the epoch of reheating that follows. We focus on the scenario where the inflaton decays slowly and perturbatively, so that there is a long period between the end of inflation and the beginning of radiation domination. The Higgs condensate decays non-perturbatively during this period, and we show that it heats the primordial plasma to much higher temperatures than would result from the slowly-decaying inflaton alone. We discuss the effect of this hot plasma on the thermalization of the inflaton's decay products, and study its phenomenological implications for the formation of cosmological relics like dark matter, with associated isocurvature fluctuations, and the restoration of the electroweak and Peccei-Quinn symmetries.