Constraints on the Cosmological Relativistic Energy Density
Astrophysics
2009-11-07 v2
Abstract
We discuss bounds on the cosmological relativistic energy density as a function of redshift, reviewing the big bang nucleosynthesis and cosmic microwave background bounds, updating bounds from large scale structure, and introducing a new bound from the magnitude-redshift relation of Type Ia supernovae. We conclude that the standard and well-motivated assumption that relativistic energy is negligible during recent epochs is not necessitated by extant data. We then demonstrate the utility of these bounds by constraining the mass and lifetime of a hypothetical massive big bang relic particle.
Keywords
Cite
@article{arxiv.astro-ph/0110533,
title = {Constraints on the Cosmological Relativistic Energy Density},
author = {Andrew R. Zentner and Terry P. Walker},
journal= {arXiv preprint arXiv:astro-ph/0110533},
year = {2009}
}
Comments
9 pages, 5 figures. Minor changes to reflect referee's comments. Accepted for publication in Phys. Rev. D. Scheduled for 15 March, 2002