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arXiv · 1611.03037

Anisotopic inflation with a non-abelian gauge field in Gauss-Bonnet gravity

Sayantani Lahiri
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Abstract

In presence of Gauss-Bonnet corrections, we study anisotropic inflation aided by a massless $SU(2)$ gauge field where both the gauge field and the Gauss-Bonnet term are non-minimally coupled to the inflaton. In this scenario, under slow-roll approximations, the anisotropic inflation is realized as an attractor solution with quadratic forms of inflaton potential and Gauss-Bonnet coupling function. We show that the degree of anisotropy is proportional to the additive combination of two slow-roll parameters of the theory. The anisotropy may become either positive or negative similar to the non-Gauss-Bonnet framework, a feature of the model for anisotropic inflation supported by a non-abelian gauge field but the effect of Gauss-Bonnet term further enhances or suppresses the generated anisotropy.

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Sayantani Lahiri. 2016-11-09. Anisotopic inflation with a non-abelian gauge field in Gauss-Bonnet gravity. https://doi.org/10.1088/1475-7516%2F2017%2F01%2F022

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