Realization of blue spectrum in generalized Galileon super-inflation models

TL;DR

This paper demonstrates how generalized Galileon super-inflation models can produce a blue-tilted tensor spectrum while avoiding ghost instabilities by incorporating specific non-canonical kinetic terms and Galileon-like contributions.

Contribution

It introduces a novel super-inflation model with non-canonical kinetic terms that achieves a blue tensor tilt and remains ghost-free due to Galileon-like modifications.

Findings

Realization of super-inflation with blue tensor tilt

Avoidance of ghost instabilities through Galileon terms

Potential implications for primordial gravitational wave spectra

Abstract

In the spirit of Galileon inflation and by considering some sorts of non-canonical kinetic terms in the action, we realize a stage of super-inflation leading to a blue-tilted tensor perturbation. We show also that addition of Galileon-like term to the action leads to avoidance of ghost instabilities in this setup.