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arXiv · 1002.3659

Slow-roll inflation in (R+R*4) gravity

S. Kaneda·S. V. Ketov·N. Watanabe
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Abstract

We reconsider the toy-model of topological inflation, based on the R*4-modified gravity. By using its equivalence to the certain scalar-tensor gravity model in four space-time dimensions, we compute the inflaton scalar potential and investigate a possibility of inflation. We confirm the existence of the slow-roll inflation with an exit. However, the model suffers from the eta-problem that gives rise to the unacceptable value of the spectral index n_s of scalar perturbations.

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S. Kaneda, S. V. Ketov, N. Watanabe. 2010-04-21. Slow-roll inflation in (R+R*4) gravity. https://doi.org/10.1088/0264-9381%2F27%2F14%2F145016

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