Non-minimal coupling in inflation and inflating with the Higgs boson

TL;DR

This paper investigates how non-minimal coupling between a scalar field and gravity affects inflation, showing that even small couplings can make the Standard Model Higgs suitable as the inflaton, aligning with observational data.

Contribution

It demonstrates that small non-minimal couplings enable the Higgs field to serve as the inflaton, relaxing previous constraints on the self-coupling parameter.

Findings

Large non-minimal coupling relaxes self-coupling constraints.

Small non-minimal coupling ($\xi extgreater10^{-3}$) aligns Higgs inflation with WMAP5 data.

Higgs field can be a viable inflaton with minimal coupling modifications.

Abstract

We analyse the effect of the non-minimal coupling of the form $\xi\phi^2R/2$ on the single field inflation. If the non-minimal coupling is large, it relaxes the constraint on the field self coupling, making it possible to use the Standard Model Higgs field as the inflaton. At the same time, even small non-minimal coupling constant, $\xi\gtrsim10^{-3}$, brings the usual inflaton with quartic potential in agreement with the WMAP5 observations.