Primordial Abundances of ^6Li, ^9Be, and ^11B with Neutrino Degeneracy and Gravitational Constant Variation

Abstract

Recent measurements of deuterium abundances from QSO absorption spectra show two conflicting numbers, which differ by an order of magnitude. Allowing the neutrino degeneracy together with gravitational constant variation at the epoch of primordial nucleosynthesis, the implication of these observations on the ^6Li, ^9Be and ^11B abundances will be discussed. Within the permitted ranges consistent with D, ^4He and ^7Li, we observe the strong ηdependence of ^11B as in SBBN but no significant dependence of ^6Li and ^9Be on the baryon number density is observed. The predictions of ^6Li and ^9Be for low and high deuterium differ by an order of magnitude and predictions for ^11B differ by several orders of magnitude at most and vary with η.