Higgs condensation as an unwanted curvaton

TL;DR

The paper investigates how Higgs field fluctuations during inflation can act as a curvaton, contributing to reheating but producing excessive density fluctuations, thus constraining certain inflation models with a long kination phase.

Contribution

It demonstrates that Higgs condensates can serve as a curvaton in specific inflation scenarios, revealing limitations for Standard Model parameters in models with prolonged kination.

Findings

Higgs condensates can reheat the universe via gravitational particle production.

Higgs curvaton leads to density fluctuations too large for Standard Model parameters.

Inflation models with long kination regimes are incompatible with observed density fluctuations.

Abstract

During inflation in the early universe, the Higgs field continuously acquires long-wave quantum fluctuations. They accumulate to yield a non-vanishing value with an exponentially large correlation length. We study consequences of such Higgs condensations to show that, in inflation models where the universe is reheated through gravitational particle production at the transition to the kination regime, they not only contribute to reheat the universe but also act as a curvaton. Unfortunately, however, for parameters of the Standard Model Higgs field, this curvaton produces density fluctuations too large, so the inflation models followed by a long kination regime are ruled out.