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arXiv · 1001.1897

Slow-roll inflation with a Gauss-Bonnet correction

Zong-Kuan Guo·Dominik J. Schwarz
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Abstract

We consider slow-roll inflation for a single scalar field with an arbitrary potential and an arbitrary nonminimal coupling to the Gauss-Bonnet term. By introducing a combined hierarchy of Hubble and Gauss-Bonnet flow functions, we analytically derive the power spectra of scalar and tensor perturbations. The standard consistency relation between the tensor-to-scalar ratio and the spectral index of tensor perturbations is broken. We apply this formalism to a specific model with a monomial potential and an inverse monomial Gauss-Bonnet coupling and constrain it by the 7-year Wilkinson Microwave Anisotropy Probe data. The Gauss-Bonnet term with a positive (or negative) coupling may lead to a reduction (or enhancement) of the tensor-to-scalar ratio and hence may revive the quartic potential ruled out by recent cosmological data.

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Zong-Kuan Guo, Dominik J. Schwarz. 2010-06-09. Slow-roll inflation with a Gauss-Bonnet correction. https://doi.org/10.1103/physrevd.81.123520

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