Scalar perturbations in p-nflation: the 3-form case

TL;DR

This paper analyzes scalar perturbations in p-nflation driven by a 3-form field, finding that curvature perturbations decay over time, implying additional fields are needed for realistic CMB fluctuations.

Contribution

It provides the first calculation of the primordial scalar spectrum for 3-form inflation and highlights the decay of curvature perturbations.

Findings

Curvature perturbations decay at late times.

A non-minimally coupled 3-form alone cannot produce observed CMB fluctuations.

Additional fields are necessary for realistic inflation models.

Abstract

We calculate the primordial spectrum of scalar perturbations of the 3-form inflation and we find that the curvature perturbations decay at late times. As as result, although a non-minimally coupled massive 3-form field may drive inflation at early times, it should be assisted by other fields in order to reproduce the observed temperature fluctuations of the CMB sky.