The charged inflaton and its gauge fields: preheating and initial conditions for reheating
Abstract
We calculate particle production during inflation and in the early stages of reheating after inflation in models with a charged scalar field coupled to Abelian and nonAbelian gauge fields. A detailed analysis of the power spectra of primordial electric fields, magnetic fields and charge fluctuations at the end of inflation and preheating is provided. We carefully account for the Gauss constraints during inflation and preheating, and clarify the role of the longitudinal components of the electric field. We calculate the timescale for the backreaction of the produced gauge fields on the inflaton condensate, marking the onset of nonlinear evolution of the fields. We provide a prescription for initial conditions for lattice simulations necessary to capture the subsequent nonlinear dynamics. On the observational side, we find that the primordial magnetic fields generated are too small to explain the origin of magnetic fields on galactic scales and the charge fluctuations are well within observational bounds for the models considered in this paper.
 Authors:
 Institute of Astronomy, University of Cambridge,Madingly Road, Cambridge (United Kingdom)
 (United Kingdom)
 (United States)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572099
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 06; Other Information: PUBLISHERID: JCAP06(2016)032; OAI: oai:repo.scoap3.org:16018; ccby Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPUTERIZED SIMULATION; COSMOLOGICAL INFLATION; COSMOLOGY; ELECTRIC FIELDS; GAUGE INVARIANCE; HEAT TREATMENTS; INFLATIONARY UNIVERSE; INFLATONS; LATTICE FIELD THEORY; MAGNETIC FIELDS; MATHEMATICAL EVOLUTION; NONLINEAR PROBLEMS; PERTURBATION THEORY; SCALAR FIELDS
Citation Formats
Lozanov, Kaloian D., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, Amin, Mustafa A., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, and Physics and Astronomy Department, Rice University,6100 Main Street, Houston. The charged inflaton and its gauge fields: preheating and initial conditions for reheating. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/06/032.
Lozanov, Kaloian D., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, Amin, Mustafa A., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, & Physics and Astronomy Department, Rice University,6100 Main Street, Houston. The charged inflaton and its gauge fields: preheating and initial conditions for reheating. United States. doi:10.1088/14757516/2016/06/032.
Lozanov, Kaloian D., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, Amin, Mustafa A., Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge, and Physics and Astronomy Department, Rice University,6100 Main Street, Houston. 2016.
"The charged inflaton and its gauge fields: preheating and initial conditions for reheating". United States.
doi:10.1088/14757516/2016/06/032.
@article{osti_22572099,
title = {The charged inflaton and its gauge fields: preheating and initial conditions for reheating},
author = {Lozanov, Kaloian D. and Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge and Amin, Mustafa A. and Kavli Institute for Cosmology, University of Cambridge,Madingly Road, Cambridge and Physics and Astronomy Department, Rice University,6100 Main Street, Houston},
abstractNote = {We calculate particle production during inflation and in the early stages of reheating after inflation in models with a charged scalar field coupled to Abelian and nonAbelian gauge fields. A detailed analysis of the power spectra of primordial electric fields, magnetic fields and charge fluctuations at the end of inflation and preheating is provided. We carefully account for the Gauss constraints during inflation and preheating, and clarify the role of the longitudinal components of the electric field. We calculate the timescale for the backreaction of the produced gauge fields on the inflaton condensate, marking the onset of nonlinear evolution of the fields. We provide a prescription for initial conditions for lattice simulations necessary to capture the subsequent nonlinear dynamics. On the observational side, we find that the primordial magnetic fields generated are too small to explain the origin of magnetic fields on galactic scales and the charge fluctuations are well within observational bounds for the models considered in this paper.},
doi = {10.1088/14757516/2016/06/032},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2016,
place = {United States},
year = 2016,
month = 6
}

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