Saved in:
Bibliographic Details
Main Authors: Ghoderao, Pulkit S., Rajantie, Arttu
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2311.02173
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913369650364416
author Ghoderao, Pulkit S.
Rajantie, Arttu
author_facet Ghoderao, Pulkit S.
Rajantie, Arttu
contents We extend the formalism to calculate non-Gaussianity of primordial curvature perturbations produced by preheating in the presence of a light scalar field. The calculation is carried out in the separate universe approximation using the non-perturbative delta N formalism and lattice field theory simulations. Initial conditions for simulations are drawn from a statistical ensemble determined by modes that left the horizon during inflation, with the time-dependence of Hubble rate during inflation taken into account. Our results show that cosmic variance, i.e., the contribution from modes with wavelength longer than the size of the observable universe today, plays a key role in determining the dominant contribution. We illustrate our formalism by applying it to an observationally-viable preheating model motivated by non-minimal coupling to gravity, and study its full parameter dependence.
format Preprint
id arxiv_https___arxiv_org_abs_2311_02173
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Curvature perturbations from preheating with scale dependence
Ghoderao, Pulkit S.
Rajantie, Arttu
Cosmology and Nongalactic Astrophysics
High Energy Physics - Lattice
High Energy Physics - Theory
We extend the formalism to calculate non-Gaussianity of primordial curvature perturbations produced by preheating in the presence of a light scalar field. The calculation is carried out in the separate universe approximation using the non-perturbative delta N formalism and lattice field theory simulations. Initial conditions for simulations are drawn from a statistical ensemble determined by modes that left the horizon during inflation, with the time-dependence of Hubble rate during inflation taken into account. Our results show that cosmic variance, i.e., the contribution from modes with wavelength longer than the size of the observable universe today, plays a key role in determining the dominant contribution. We illustrate our formalism by applying it to an observationally-viable preheating model motivated by non-minimal coupling to gravity, and study its full parameter dependence.
title Curvature perturbations from preheating with scale dependence
topic Cosmology and Nongalactic Astrophysics
High Energy Physics - Lattice
High Energy Physics - Theory
url https://arxiv.org/abs/2311.02173