Red Spectral Tilt and Observable Gravity Waves in Shifted Hybrid Inflation

TL;DR

This paper explores shifted hybrid inflation models that produce a red spectral tilt and potentially observable gravity waves, aligning with WMAP data and avoiding topological defects.

Contribution

It introduces shifted hybrid inflation models with non-minimal supergravity corrections that match observational data and predict detectable tensor-to-scalar ratios.

Findings

Models support a red spectral index consistent with WMAP

Tensor-to-scalar ratio can reach 0.02, observable by Planck

Topological defects are inflated away in shifted models

Abstract

We consider supersymmetric shifted hybrid inflation models with a red tilted scalar spectral index n_s in agreement with the WMAP 7-yr central value. If non-minimal supergravity corrections are included, these models can also support a tensor-to-scalar ratio as large as r = 0.02, which may be observable by the Planck Satellite. In contrast to the standard supersymmetric hybrid inflation scenario, topological defects produced via gauge symmetry breaking are inflated away in the shifted version of the theory.