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arXiv · 1604.05326

Plateau Inflation from Random Non-Minimal Coupling

Abstract

A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength $ξ$ of the order $N_e^2$. In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of $ξ$, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes $ξ\simeq 10^4$ obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observables measured.

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BibTeXRIS

Benedict J. Broy, Dries Coone, Diederik Roest. 2016-06-21. Plateau Inflation from Random Non-Minimal Coupling. https://doi.org/10.1088/1475-7516%2F2016%2F06%2F036

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