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arXiv · 1310.5579

Inflation coupled to a Gauss-Bonnet term

Peng-Xu Jiang·Jian-Wei Hu·Zong-Kuan Guo
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Abstract

The newly released Planck CMB data place tight constraints on slow-roll inflationary models. Some of commonly discussed inflationary potentials are disfavored due mainly to the large tensor-to-scalar ratio. In this paper we show that these potentials may be in good agreement with the Planck data when the inflaton has a non-minimal coupling to the Gauss-Bonnet term. Moreover, such a coupling violates the consistency relation between the tensor spectral index and tensor-to-scalar ratio. If the tensor spectral index is allowed to vary freely, the Planck constraints on the tensor-to-scalar ratio are slightly improved.

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Peng-Xu Jiang, Jian-Wei Hu, Zong-Kuan Guo. 2013-10-21. Inflation coupled to a Gauss-Bonnet term. https://doi.org/10.1103/physrevd.88.123508

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