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arXiv · 1606.03343

Consistency relation and inflaton field redefinition in the delta N formalism

Guillem Domenech·Jinn-Ouk Gong·Misao Sasaki
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Abstract

We compute for general single-field inflation the intrinsic non-Gaussianity due to the self-interactions of the inflaton field in the squeezed limit. We recover the consistency relation in the context of the delta N formalism, and argue that there is a particular field redefinition that makes the intrinsic non-Gaussianity vanishing, thus improving the estimate of the local non-Gaussianity using the delta N formalism.

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Guillem Domenech, Jinn-Ouk Gong, Misao Sasaki. 2017-04-12. Consistency relation and inflaton field redefinition in the delta N formalism. https://doi.org/10.1016/j.physletb.2017.04.014

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