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arXiv · 1607.07872

Features from the non-attractor beginning of inflation

Yi-Fu Cai·Jinn-Ouk Gong·Dong-Gang Wang·Ziwei Wang
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Abstract

We study the effects of the non-attractor initial conditions for the canonical single-field inflation. The non-attractor stage can last only several $e$-folding numbers, and should be followed by hilltop inflation. This two-stage evolution leads to large scale suppression in the primordial power spectrum, which is favored by recent observations. Moreover we give a detailed calculation of primordial non-Guassianity due to the "from non-attractor to slow-roll" transition, and find step features in the local and equilateral shapes. We conclude that a plateau-like inflaton potential with an initial non-attractor phase yields interesting features in both power spectrum and bispectrum.

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Yi-Fu Cai, Jinn-Ouk Gong, Dong-Gang Wang, Ziwei Wang. 2016-08-07. Features from the non-attractor beginning of inflation. https://doi.org/10.1088/1475-7516%2F2016%2F10%2F017

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