Constraining fast-roll inflation

Johannes Noller

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arXiv · 1205.5796

Constraining fast-roll inflation

Johannes Noller

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Abstract

We present constraints on how far single field inflation may depart from the familiar slow-roll paradigm. Considering a fast-roll regime while requiring a (near)-scale-invariant power spectrum introduces large self-interactions for the field and consequently large and scale-dependent non-Gaussianities. Employing this signal, we use the requirement of weak-coupling together with WMAP constraints to derive bounds on generic $P(X,ϕ)$ theories of single field inflation.

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Johannes Noller. 2012-09-10. Constraining fast-roll inflation. https://arxiv.org/abs/1205.5796

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