Trail of the Higgs in the primordial spectrum

TL;DR

This paper investigates how a direct Higgs-inflaton coupling influences the primordial power spectrum, revealing oscillatory classical features and discussing implications for collider experiments.

Contribution

It introduces a model where Higgs-inflaton coupling stabilizes the Higgs during inflation and produces distinctive oscillatory features in the power spectrum.

Findings

Higgs-inflaton coupling induces oscillations in the primordial spectrum.

Classical effects dominate over quantum fluctuation features.

Implications for collider searches are discussed.

Abstract

We study the effects of the Higgs directly coupled to the inflaton on the primordial power spectrum. The quadratic coupling between the Higgs and the inflaton stabilizes the Higgs in the electroweak vacuum during inflation by inducing a large effective mass for the Higgs, which also leads to oscillatory features in the primordial power spectrum due to the oscillating classical background. Meanwhile, the features from quantum fluctuations exhibit simple monotonic k-dependence and are subleading compared to the classical contributions. We also comment on the collider searches.