Year: 2008
Type: article
Abstract: Preheating can convert superhorizon fluctuations of light scalar fields present at the end of inflation into observable density perturbations. We show in detail how lattice field theory simulations and the separate universes approximation can be used to calculate these perturbations and make predictions for the nonlinearity parameter f NL . We also present a simple approximation scheme that can reproduce these results analytically. Applying these methods to the massless preheating model, we determine the parameter values that are ruled out by too high levels of non-Gaussianity.
Authors: Alex Chambers, Arttu Rajantie
Institution: Imperial College London
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1980612049