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arXiv · 1512.00222

No-Go Theorem for Gauss-Bonnet Inflation without Inflaton Potential

Getbogi Hikmawan·Jiro Soda·Agus Suroso·Freddy P. Zen
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Abstract

Recently, an interesting inflationary scenario, named Gauss-Bonnet inflation, is proposed by Kanti et al.~\cite{Kanti:2015pda,Kanti:2015dra}. In the model, there is no inflaton potential but the inflaton couples to the Guass-Bonnet term. In the case of quadratic coupling, they find inflation occurs with graceful exit. The scenario is attractive because of the natural set-up. However, we show there exists the gradient instability in the tensor perturbations in this inflationary model. We further prove the no-go theorem for the Gauss-Bonnet inflation without an inflaton potential.

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Getbogi Hikmawan, Jiro Soda, Agus Suroso, Freddy P. Zen. 2015-12-01. No-Go Theorem for Gauss-Bonnet Inflation without Inflaton Potential. https://doi.org/10.1103/physrevd.93.068301

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