On the generation of density perturbations at the end of inflation

Abstract

Recently a mechanism was proposed whereby the primordial density perturbations are generated at the end of inflation. We continue the analysis of the proposed model of this mechanism and calculate the maximum extent to which the density perturbations produced via this model can dominate over those of the standard inflationary paradigm. In addition, we provide a straightforward variation of this model which allows for greater amplification of the density perturbations. Finally, we show that a variation in the implementation of the original model results in significant non-gaussianities in the resulting spectrum of density perturbations. The level of non-gaussianities can be made to saturate the current observational bound.

Comments: 7 pages, no figures. v2: significant revisions to section IV, other comments clarified, references added. v3: typo corrected, version that appears in PRD. v4: some misstatements in the background section corrected, no change in results. v5: erratum added to correct the predictions of section V.B, reference added