Fermion production from preheating-amplified metric perturbations

Abstract

We study gravitational creation of light fermions in the presence of classical scalar metric perturbations about a flat Friedmann-Lemaitre- Robertson-Walker (FLRW) background. These perturbations can be large during preheating, breaking the conformal flatness of the background spacetime. We compute numerically the total number of particles generated by the modes of the metric perturbations which have grown sufficiently to become classical. In the absence of inhomogeneities massless fermions are not gravitationally produced, and then this effect may be relevant for abundance estimates of light gravitational relics.

17 pages, 7 figures, accepted for publication in Nuclear Physics B

References in corpus (4)

• Enhancement of superhorizon scale inflationary curvature perturbations
• Cosmological perturbations from multi-field inflation in generalized Einstein theories
• Coupled fields in external background with application to nonthermal production of gravitinos
• Massive fermion production in nonsingular superstring cosmology

Cited by in corpus (13)

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• On the Construction of Nonsingular Pre-Big-Bang and Ekpyrotic Cosmologies and the Resulting Density Perturbations
• Correlation-consistency cartography of the double inflation landscape
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• When can preheating affect the CMB?
• Inflationary entanglement
• Cosmological density perturbations from perturbed couplings
• Quantum entanglement in cosmology
• Production of ultralight dark matter from inflationary spectator fields
• Non-linear Preheating with Scalar Metric Perturbations
• Chaotic dynamics in preheating after inflation
• Comparing geometric and gravitational particle production in Jordan and Einstein frames
• Constraining the primordial spectrum of metric perturbations from gravitino and moduli production