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تسجيل مستخدم جديدNucleosynthesis in Power-Law Cosmologies
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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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In a class of models designed to solve the cosmological constant problem by coupling scalar or tensor classical fields to the space-time curvature, the universal scale factor grows as a power law in the age, $a propto t^alpha$, regardless of the matt
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