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Nucleosynthesis in Power-Law Cosmologies

M. Kaplinghat·G. Steigman·T. P. Walker
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Abstract

We have recently considered cosmologies in which the Universal scale factor varies as a power of the age of the Universe and concluded that they cannot satisfy the observational constraints on the present age, the magnitude-redshift relation for SN Ia, and the primordial element (D, He3, He4, and Li7) abundances. This claim has been challenged in a proposal that suggested a high baryon density model (Omega_B*h*h = 0.3) with an expansion factor varing linearly with time could be consistent with the observed abundance of primoridal helium-4, while satisfying the age and magnitude-redshift constraints. In this paper we further explore primordial nucleosynthesis in generic power-law cosmologies, including the linear case, concluding that models selected to satisfy the other observational constraints are incapable of accounting for all the light element abundances.

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M. Kaplinghat, G. Steigman, T. P. Walker. 2000-03-28. Nucleosynthesis in Power-Law Cosmologies. https://doi.org/10.1103/physrevd.61.103507

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