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Title: A scenario for inflationary magnetogenesis without strong coupling problem

Abstract

Cosmological magnetic fields pervade the entire universe, from small to large scales. Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced during inflation. However, finding consistent scenarios for inflationary magnetogenesis is a challenging theoretical problem. The requirements to avoid an excessive production of electromagnetic energy, and to avoid entering a strong coupling regime characterized by large values for the electromagnetic coupling constant, typically allow one to generate only a tiny amplitude of magnetic field during inflation. We propose a scenario for building gauge-invariant models of inflationary magnetogenesis potentially free from these issues. The idea is to derivatively couple a dynamical scalar, not necessarily the inflaton, to fermionic and electromagnetic fields during the inflationary era. Such couplings give additional freedom to control the time-dependence of the electromagnetic coupling constant during inflation. This fact allows us to find conditions to avoid the strong coupling problems that affect many of the existing models of magnetogenesis. We do not need to rely on a particular inflationary set-up for developing our scenario, that might be applied to different realizations of inflation. On the other hand, specific requirements have to be imposed onmore » the dynamics of the scalar derivatively coupled to fermions and electromagnetism, that we are able to satisfy in an explicit realization of our proposal.« less

Authors:
 [1]
  1. Department of Physics, Swansea University, Swansea, SA2 8PP U.K. (United Kingdom)
Publication Date:
OSTI Identifier:
22525936
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COUPLING CONSTANTS; ELECTROMAGNETIC FIELDS; ELECTROMAGNETISM; FERMIONS; GAUGE INVARIANCE; INFLATIONARY UNIVERSE; INTERGALACTIC SPACE; MAGNETIC FIELDS; POTENTIALS; SCALARS; STRONG-COUPLING MODEL; TIME DEPENDENCE; UNIVERSE

Citation Formats

Tasinato, Gianmassimo, E-mail: gianmassimo.tasinato@port.ac.uk. A scenario for inflationary magnetogenesis without strong coupling problem. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/03/040.
Tasinato, Gianmassimo, E-mail: gianmassimo.tasinato@port.ac.uk. A scenario for inflationary magnetogenesis without strong coupling problem. United States. doi:10.1088/1475-7516/2015/03/040.
Tasinato, Gianmassimo, E-mail: gianmassimo.tasinato@port.ac.uk. Sun . "A scenario for inflationary magnetogenesis without strong coupling problem". United States. doi:10.1088/1475-7516/2015/03/040.
@article{osti_22525936,
title = {A scenario for inflationary magnetogenesis without strong coupling problem},
author = {Tasinato, Gianmassimo, E-mail: gianmassimo.tasinato@port.ac.uk},
abstractNote = {Cosmological magnetic fields pervade the entire universe, from small to large scales. Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced during inflation. However, finding consistent scenarios for inflationary magnetogenesis is a challenging theoretical problem. The requirements to avoid an excessive production of electromagnetic energy, and to avoid entering a strong coupling regime characterized by large values for the electromagnetic coupling constant, typically allow one to generate only a tiny amplitude of magnetic field during inflation. We propose a scenario for building gauge-invariant models of inflationary magnetogenesis potentially free from these issues. The idea is to derivatively couple a dynamical scalar, not necessarily the inflaton, to fermionic and electromagnetic fields during the inflationary era. Such couplings give additional freedom to control the time-dependence of the electromagnetic coupling constant during inflation. This fact allows us to find conditions to avoid the strong coupling problems that affect many of the existing models of magnetogenesis. We do not need to rely on a particular inflationary set-up for developing our scenario, that might be applied to different realizations of inflation. On the other hand, specific requirements have to be imposed on the dynamics of the scalar derivatively coupled to fermions and electromagnetism, that we are able to satisfy in an explicit realization of our proposal.},
doi = {10.1088/1475-7516/2015/03/040},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2015,
place = {United States},
year = {Sun Mar 01 00:00:00 EST 2015},
month = {Sun Mar 01 00:00:00 EST 2015}
}