On electroweak metastability and Higgs inflation

TL;DR

This paper reviews Higgs inflation within the Standard Model extended by a non-minimal gravity coupling, showing how large couplings can enable inflation even with a metastable Higgs potential.

Contribution

It demonstrates that a non-minimal coupling to gravity can make metastable Higgs potentials viable for inflation, extending previous analyses of Higgs stability.

Findings

Large non-minimal couplings flatten the Higgs potential at high energies.

Metastable configurations can support inflation with appropriate coupling strength.

The effective Higgs potential exhibits two minima, influencing inflationary dynamics.

Abstract

For the central values of the relevant experimental inputs, that is the strong coupling constant and the top quark and Higgs masses, the effective Higgs potential displays two minima, one at the electroweak scale and a deeper one at high energies. We review the phenomenology of the Higgs inflation model, extending the Standard Model to include a non-minimal coupling to gravity; as recently shown [1], even configurations that would be metastable in the Standard Model, become viable for inflation if the non-minimal coupling is large enough to flatten the Higgs potential at field values below the barrier between the minima.