Higgs inflation: consistency and generalisations

TL;DR

The paper analyzes the self-consistency of Higgs inflation with a large non-minimal gravity coupling by introducing a background-dependent EFT cutoff and an inflationary EFT anchored by an asymptotic shift symmetry. It demonstrates that, in both Jordan and Einstein frames, the cutoff exceeds the characteristic energy scales during inflation and reheating, keeping the semiclassical treatment valid. Quantum corrections are organized using an exponential-type potential and derivative-coupling terms that preserve the flatness of the inflaton potential, yielding robust slow-roll predictions (e.g., a small $r$). Linking inflationary parameters to collider physics requires specific UV completion assumptions, notably suppression of power-law divergences; the framework is general and extends to a broad class of models with asymptotic symmetries, offering a unified EFT approach to inflation with potential UV completions tied to scale-invariant ideas.

Abstract

We analyse the self-consistency of inflation in the Standard Model, where the Higgs field has a large non-minimal coupling to gravity. We determine the domain of energies in which this model represents a valid effective field theory as a function of the background Higgs field. This domain is bounded above by the cutoff scale which is found to be higher than the relevant dynamical scales throughout the whole history of the Universe, including the inflationary epoch and reheating. We present a systematic scheme to take into account quantum loop corrections to the inflationary calculations within the framework of effective field theory. We discuss the additional assumptions that must be satisfied by the ultra-violet completion of the theory to allow connection between the parameters of the inflationary effective theory and those describing the low-energy physics relevant for the collider experiments. A class of generalisations of inflationary theories with similar properties is constructed.