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Big-bang nucleosynthesis in Brans-Dicke cosmology with a varying $Λ$ term related to WMAP

R. Nakamura·M. Hashimoto·S. Gamow·K. Arai
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Abstract

We investigate the big-bang nucleosynthesis in a Brans-Dicke model with a varying $Λ$ term using the Monte-Carlo method and likelihood analysis. It is found that the cosmic expansion rate differs appreciably from that of the standard model. The produced abundances of $^4$He, D, and barely Li are consistent with the observed ones within the uncertainties in nuclear reaction rates when the baryon to photon ratio $η= (5.47 - 6.64)\times 10^{-10}$, which is in agreement with the value deduced from WMAP.

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R. Nakamura, M. Hashimoto, S. Gamow, K. Arai. 2005-09-05. Big-bang nucleosynthesis in Brans-Dicke cosmology with a varying $Λ$ term related to WMAP. https://doi.org/10.1051/0004-6361%3A20042618

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