English

Non-Gaussianity from massless preheating

Astrophysics 2008-09-30 v2 High Energy Physics - Phenomenology

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 fNL . 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.

Keywords

Cite

@article{arxiv.0805.4795,
  title  = {Non-Gaussianity from massless preheating},
  author = {Alex Chambers and Arttu Rajantie},
  journal= {arXiv preprint arXiv:0805.4795},
  year   = {2008}
}

Comments

26 pages, 9 figures, 1 table; erratum added

R2 v1 2026-06-21T10:45:52.113Z