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arXiv · 1203.3558

Separable and non-separable multi-field inflation and large non-Gaussianity

Anupam Mazumdar·Lingfei Wang
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Abstract

In this paper we provide a general framework based on $δN$ formalism to estimate the cosmological observables pertaining to the cosmic microwave background radiation for non-separable potentials, and for generic \emph{end of inflation} boundary conditions. We provide analytical and numerical solutions to the relevant observables by decomposing the cosmological perturbations along the curvature and the isocurvature directions, \emph{instead of adiabatic and entropy directions}. We then study under what conditions large bi-spectrum and tri-spectrum can be generated through phase transition which ends inflation. In an illustrative example, we show that large $f_{NL}\sim {\cal O}(80)$ and $τ_{NL}\sim {\cal O}(20000)$ can be obtained for the case of separable and non-separable inflationary potentials.

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Anupam Mazumdar, Lingfei Wang. 2012-09-06. Separable and non-separable multi-field inflation and large non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2012%2F09%2F005

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