Relaxing Nucleosynthesis Constraints on Brans-Dicke Theories
Abstract
We reconsider constraints on Brans-Dicke theories arising from the requirement of successful Big Bang Nucleosynthesis. Such constraints typically arise by imposing that the universe be radiation-dominated at early times, and therefore restricting the contribution that a Brans-Dicke scalar could make to the energy budget of the universe. However, in this paper we show how the dynamics of the Brans-Dicke scalar itself can mimic a portion of the radiation contribution, thereby allowing successful nucleosynthesis with a sizable contribution to the total cosmic energy density. This possibility significantly relaxes the existing bounds on Brans-Dicke fields, and opens the door to new possibilities for early universe cosmology. The necessary fine tunings required by such an arrangement are identified and discussed.
Keywords
Cite
@article{arxiv.astro-ph/0510359,
title = {Relaxing Nucleosynthesis Constraints on Brans-Dicke Theories},
author = {Antonio De Felice and Gianpiero Mangano and Pasquale D. Serpico and Mark Trodden},
journal= {arXiv preprint arXiv:astro-ph/0510359},
year = {2008}
}
Comments
9 pages, 2 figures, uses RevTeX. Dedicated to Rafael Sorkin, on the occasion of his 60th birthday, and to celebrate his wonderful contributions to physics. Added references, a few comments and numerical results