Kinetically Modified Non-Minimal Higgs Inflation in Supergravity

TL;DR

This paper develops a supergravity-based Higgs inflation model with a shift symmetry that aligns well with recent cosmic microwave background observations, ensuring sub-Planckian field values and maintaining unitarity.

Contribution

It introduces a kinetically modified non-minimal Higgs inflation model in supergravity with a specific superpotential and Kahler potential that fit observational data.

Findings

Matches BICEP2/Keck Array and Planck data

Allows sub-Planckian inflaton values

Maintains perturbative unitarity up to the Planck scale

Abstract

We consider models of chaotic inflation driven by the real parts of a conjugate pair of Higgs superfields involved in the spontaneous breaking of a grand unification symmetry at a scale assuming its supersymmetric value. We combine a superpotential, which is uniquely determined by applying a continuous R symmetry, with a class of logarithmic or semi-logarithmic Kahler potentials which exhibit a prominent shift-symmetry with a tiny violation, whose strengths are quantified by c- and c+ respectively. The inflationary observables provide an excellent match to the recent BICEP2/Keck Array and Planck results setting 3.5x10^-3<=r+-=c+/c-<=1/N where N=3 or 2 is the prefactor of the logarithm. Inflation can be attained for subplanckian inflaton values with the corresponding effective theories retaining the perturbative unitarity up to the Planck scale.