Massive Gauge-flation

TL;DR

This paper modifies the Gauge-flation model by adding mass terms to better align its predictions with Planck data, demonstrating it can produce viable slow-roll inflation consistent with observations.

Contribution

The study introduces a massive extension to Gauge-flation, showing it can achieve slow-roll inflation and match observational constraints on spectral index and tensor-to-scalar ratio.

Findings

Mass term modifies the $n_s$ vs. $r$ relation to fit data

The model achieves sufficient e-foldings for inflation

Numerical analysis supports the viability of the massive Gauge-flation

Abstract

Gauge-flation model at zeroth order in cosmological perturbation theory offers an interesting scenario for realizing inflation within a particle physics context, allowing us to investigate interesting possible connections between inflation and the subsequent evolution of the Universe. Difficulties, however, arise at the perturbative level, thus motivating a modification of the original model. In order to agree with the latest Planck observations, we modify the model such that the new dynamics can produce a relation between the spectral index $n_{s}$ and the tensor-to-scalar ratio $r$ allowed by the data. By including an identical mass term for each of the fields of the system, we find interesting dynamics leading to slow-roll inflation of the right length. The presence of the mass term has the potential to modify the $n_{s}$ vs. $r$ relation so as to agree with the data. As a first step, we study the model at zeroth order in cosmological perturbation theory, finding the conditions required for slow-roll inflation and the number of e-foldings of inflation. Numerical solutions are used to explore the impact of the mass term. We conclude that the massive version of Gauge-flation offers a viable inflationary model.