A large scale coherent magnetic field: interactions with free streaming particles and limits from the CMB
Cosmology and Nongalactic Astrophysics
2012-01-11 v1
Abstract
We study a homogeneous and nearly-isotropic Universe permeated by a homogeneous magnetic field. Together with an isotropic fluid, the homogeneous magnetic field, which is the primary source of anisotropy, leads to a plane-symmetric Bianchi I model of the Universe. However, when free-streaming relativistic particles are present, they generate an anisotropic pressure which counteracts the one from the magnetic field such that the Universe becomes isotropized. We show that due to this effect, the CMB temperature anisotropy from a homogeneous magnetic field is significantly suppressed if the the neutrino masses are smaller than 0.3 eV.
Keywords
Cite
@article{arxiv.1102.5235,
title = {A large scale coherent magnetic field: interactions with free streaming particles and limits from the CMB},
author = {Julian Adamek and Ruth Durrer and Elisa Fenu and Marc Vonlanthen},
journal= {arXiv preprint arXiv:1102.5235},
year = {2012}
}
Comments
20 pages, 5 figures (JHEP style) - submitted to JCAP