Relaxing nucleosynthesis constraints on Brans-Dicke theories
- Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom)
- INFN, Sezione di Napoli, and Dipartimento di Scienze Fisiche Universita di Napoli Federico II Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Naples (Italy)
- Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Munich (Germany)
- Department of Physics, Syracuse University, Syracuse, New York 13244-1130 (United States)
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 radiation-dominated kinematics, thereby allowing successful nucleosynthesis with a sizable contribution to the total cosmic energy density. In other words Newton's constant may dynamically acquire values quite different from that today, even though the evolution mimics radiation domination. 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.
- OSTI ID:
- 20864085
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 74, Issue 10; Other Information: DOI: 10.1103/PhysRevD.74.103005; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
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