Large-scale magnetic fields from inflation in dilaton electromagnetism
Abstract
The generation of large-scale magnetic fields is studied in dilaton electromagnetism in inflationary cosmology, taking into account the dilaton's evolution throughout inflation and reheating until it is stabilized with possible entropy production. It is shown that large-scale magnetic fields with observationally interesting strength at the present time could be generated if the conformal invariance of the Maxwell theory is broken through the coupling between the dilaton and electromagnetic fields in such a way that the resultant quantum fluctuations in the magnetic field has a nearly scale-invariant spectrum. If this condition is met, the amplitude of the generated magnetic field could be sufficiently large even in the case huge amount of entropy is produced with the dilution factor as the dilaton decays.
Cite
@article{arxiv.astro-ph/0310824,
title = {Large-scale magnetic fields from inflation in dilaton electromagnetism},
author = {Kazuharu Bamba and J. Yokoyama},
journal= {arXiv preprint arXiv:astro-ph/0310824},
year = {2008}
}
Comments
28 pages, 5 figures, the version accepted for publication in Phys. Rev. D; some references are added