Year: 2002
Type: article
Abstract: This article investigates the generation of non-Gaussianity during inflation. In the context of multifield inflation, we detail a mechanism that can create significant primordial non-Gaussianities in the adiabatic mode while preserving the scale invariance of the power spectrum. This mechanism is based on the generation of non-Gaussian isocurvature fluctuations which are then transferred to the adiabatic modes through a bend in the classical inflaton trajectory. Natural realizations involve quartic self-interaction terms for which a full computation can be performed. The expected statistical properties of the resulting metric fluctuations are shown to be the superposition of a Gaussian and a non-Gaussian contribution of the same variance. The relative weight of these two contributions is related to the total bending in field space. We explicit the non-Gaussian probability distribution function which appears to be described by a single new parameter. Only two new parameters therefore suffice in describing the non-Gaussianity.
Authors: Francis Bernardeau, Jean-Philippe Uzan
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2242501075