English

Magnetogenesis in Matter - Ekpyrotic Bouncing Cosmology

General Relativity and Quantum Cosmology 2017-04-20 v2

Abstract

In the recent past there have been many attempts to associate the generation of primordial magnetic seed fields with the inflationary era, but with limited success. We thus take a different approach by using a model for nonsingular bouncing cosmology. A coupling of the electromagnetic Lagrangian FμνFμνF_{\mu\nu}F^{\mu\nu} with a non background scalar field has been considered for the breaking of conformal invariance. We have shown that non singular bouncing cosmology supports magnetogenesis evading the long standing back reaction and strong coupling problems which have plagued inflationary magnetogenesis. In this model, we have achieved a scale invariant power spectrum for the parameter range compatible with observed CMB anisotropies. The desired strength of the magnetic field has also been obtained that goes in accordance with present observations. It is also important to note that no BKL instability arises within this parameter range. The energy scales for different stages of evolution of the bouncing model are so chosen that they solve the problems of Standard Big Bang cosmology as well.

Keywords

Cite

@article{arxiv.1612.08556,
  title  = {Magnetogenesis in Matter - Ekpyrotic Bouncing Cosmology},
  author = {Ratna Koley and Sidhartha Samtani},
  journal= {arXiv preprint arXiv:1612.08556},
  year   = {2017}
}

Comments

15 pages, 2 figures

R2 v1 2026-06-22T17:34:58.063Z