SUGRA New Inflation with Heisenberg Symmetry

TL;DR

This paper introduces a supergravity-based new inflation model protected by Heisenberg symmetry, linking inflation to high-energy phase transitions and making specific, testable predictions for primordial perturbations.

Contribution

It presents a novel supergravity inflation model using Heisenberg symmetry, allowing for gauge non-singlet inflatons and discrete predictions for cosmological parameters.

Findings

Predictions for spectral index n_s align with Planck 2013 data.

Model links inflation to GUT or flavor symmetry breaking.

Heisenberg symmetry ensures flatness of the inflaton potential.

Abstract

We propose a realisation of 'new inflation' in supergravity (SUGRA), where the flatness of the inflaton potential is protected by a Heisenberg symmetry. Inflation can be associated with a particle physics phase transition, with the inflaton being a (D-flat) direction of Higgs fields which break some symmetry at high energies, e.g. of GUT Higgs fields or of Higgs fields for flavour symmetry breaking. This is possible since compared to a shift symmetry, which is usually used to protect a flat inflaton potential, the Heisenberg symmetry is compatible with a (gauge) non-singlet inflaton field. In contrast to conventional new inflation models in SUGRA, where the predictions depend on unknown parameters of the K"ahler potential, the model with Heisenberg symmetry makes discrete predictions for the primordial perturbation parameters which depend only on the order n at which the inflaton appears in the effective superpotential. The predictions for the spectral index n_s can be close to the best-fit value of the latest Planck 2013 results.