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arXiv · 1401.5212

Multi-Natural Inflation

Michael Czerny·Fuminobu Takahashi
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Abstract

We propose a multi-natural inflation model in which the single-field inflaton potential consists of two or more sinusoidal potentials that are comparable in size, but have different periodicity with a possible non-zero relative phase. The model is versatile enough to realize both large-field and small-field inflation. We show that, in a model with two sinusoidal potentials, the predicted values of the spectral index and tensor-to-scalar ratio lie within the $1σ$ region of the Planck data. In particular, there is no lower bound on the decay constants in contrast to the original natural inflation. We also show that, in a certain limit, multi-natural inflation can be approximated by a hilltop quartic inflation model.

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Michael Czerny, Fuminobu Takahashi. 2014-05-29. Multi-Natural Inflation. https://doi.org/10.1016/j.physletb.2014.04.039

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