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Relaxing Nucleosynthesis Constraints on Brans-Dicke Theories

Antonio De Felice·Gianpiero Mangano·Pasquale D. Serpico·Mark Trodden
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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.

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Antonio De Felice, Gianpiero Mangano, Pasquale D. Serpico, Mark Trodden. 2006-11-25. Relaxing Nucleosynthesis Constraints on Brans-Dicke Theories. https://doi.org/10.1103/physrevd.74.103005

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