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Nongaussian Isocurvature Perturbations from Inflation

A. Linde·V. Mukhanov
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Abstract

We present a class of very simple inflationary models of two scalar fields which leads to nongaussian isothermal perturbations with "blue" spectrum, n > 1. One of the models is inspired by supersymmetric theories where light scalar fields naturally acquire masses of the order of the Hubble constant H during inflation. Another model presumes that one of the fields has a nonminimal interaction with gravity. By a slight modification of parameters of these models one can obtain either gaussian isothermal perturbations, or nongaussian adiabatic perturbations with n > 1.

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A. Linde, V. Mukhanov. 1996-11-19. Nongaussian Isocurvature Perturbations from Inflation. https://doi.org/10.1103/physrevd.56.r535

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