Related papers: Big-bang Nucleosynthesis Enters the Precision Era
We examine Big Bang nucleosynthesis (BBN) in the case of inhomogenous neutrino degeneracy, in the limit where the fluctuations are sufficiently small on large length scales that the present-day element abundances are homogeneous. We…
Two new high-precision measurements of the deuterium abundance from absorbers along the line of sight to the quasar PKS1937--1009 were presented. The absorbers have lower neutral hydrogen column densities (N(HI) $\approx$ 18\,cm$^{-2}$)…
The impact of recent results on Big Bang Nucleosynthesis is assessed. These include the Planck likelihood distributions for the baryon density; recent progress in helium abundance determinations; and a recent cross section measurement for…
This paper is superseded by Arxiv:1911.07334. Big-bang nucleosynthesis (BBN) is a valuable tool to constrain the physics of the early universe and is the only probe of the radiation-dominated epoch. A fundamental assumption in BBN is that…
Recently it is reported that there is the discrepancy between big bang nucleosynthesis theory and observations (BBN crisis). We show that BBN predictions agree with the primordial abundances of light elements, He4, D, He3 and Li7 inferred…
Within the standard big bang nucleosynthesis (BBN) and cosmic microwave background (CMB) framework, the baryon density measured by the Wilkinson Microwave Anisotropy Probe (WMAP) or the primordial D abundance is much higher than the one…
The current status of big bang nucleosynthesis is summarized. Particular attention is paid to recent observations of He4 and Li7 and their systematic uncertainties. Be and B are also discussed in connection to recent Li7 observations and…
The measurement of the cosmic microwave background has strongly constrained the cosmological parameters of the Universe. When the measured density of baryons (ordinary matter) is combined with standard Big Bang nucleosynthesis calculations,…
Comparing Big Bang Nucleosynthesis predictions with the light element abundances inferred from observational data, we can obtain the strong constraints on some neutrino properties, e.g. number of neutrino species, mass, lifetime. Recently…
We have studied finite temperature corrections to the baryon transport cross sections and diffusion coefficients. These corrections are based upon the recently computed renormalized electron mass and the modified state density due to the…
Big Bang Nucleosynthesis can provide, via constraints on the expansion rate at that time, limits on possible variations in Newton's Constant, $G$. The original analyses were performed before an independent measurement of the…
The primordial abundances of Deuterium, he4, and li7 are crucial to determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). li6 which is only produced in tiny quantities and it is…
Abundances of light nuclei formed during primordial nucleosynthesis are predicted by Standard Big Bang Model. The latest data from WMAP, with precision's higher than ever before, provides a motivation to determine theoretical higher order…
We determine the influence of a variation of the fundamental ``constants'' on the predicted helium abundance in Big Bang Nucleosynthesis. The analytic estimate is performed in two parts: the first step determines the dependence of the…
Primordial or big bang nucleosynthesis (BBN) is now a parameter free theory whose predictions are in good overall agreement with observations. However, the 7Li calculated abundance is significantly higher than the one deduced from…
Big bang nucleosynthesis constraints on baryon isocurvature perturbations are determined. A simple model ignoring the effects of the scale of the perturbations is first reviewed. This model is then extended to test the claim that large…
We analyze the effect of variation of fundamental couplings and mass scales on primordial nucleosynthesis in a systematic way. The first step establishes the response of primordial element abundances to the variation of a large number of…
Direct observations of the supposedly universal primordial deuterium abundance imply a relatively large baryon density $\Omega_B= (0.019-0.030)h^{-2}$ (95% C.L.). On the other hand, concordance between the previously accepted $^4 He$ and…
Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…
The primordial abundances of deuterium and of helium-3, produced during big bang nucleosynthesis, depend sensitively on the baryon density. Thus, the observed abundances of D and \he may provide useful ``baryometers'' provided the evolution…