Related papers: Primordial Nucleosynthesis: Theory and Observation…
Big bang nucleosynthesis has long provided the primary determination of the cosmic baryon density $\omb h^2$, or equivalently the baryon-to-photon ratio, \eta. Recently, data on CMB anisotropies have become increasingly sensitive to \eta.…
The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of…
We consider Big Bang Nucleosynthesis (BBN) with long lived charged massive particles. Before decaying, the long lived charged particle recombines with a light element to form a bound state like a hydrogen atom. This effect modifies the…
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…
The role of neutrinos in big bang nucleosynthesis is reviewed. Neutrino oscillations in the early universe both in resonance and non-resonance case are briefly discussed. BBN and supernova limits on heavy sterile neutrinos with the mass in…
There is continued interest in the possibility that big bang nucleosynthesis may produce significant quantities of Be and B. In this paper we reevaluate the primordial abundances taking into account uncertainties in reactions rates. We…
The primordial abundances of the light nuclides produced by Big Bang Nucleosynthesis (BBN) during the first 20 minutes in the evolution of the Universe are sensitive to the universal density of baryons and to the expansion rate of the early…
We discuss the effects of a possible time variation of the Newton constant $G_{\rm N}$ on light elements production in Big Bang Nucleosyntesis (BBN). We provide analytical estimates for the dependence of primordial abundances on the value…
We include the coupling of a heavy sterile neutrino with active neutrinos in the calculation of primordial abundances of light-nuclei. We calculate neutrino distribution functions and primordial abundances, as functions depending on a…
We investigate Big Bang nucleosynthesis (hereafter, BBN) in a cosmic environment characterized by a distribution of small-scale matter/antimatter domains. Production of antimatter domains in a baryo-asymmetric universe is predicted in some…
A new observation of D in a primordial gas cloud, made using the high resolution spectrograph at the Keck telescope, indicates an abundance $ D/H =(1.9-2.5) \times 10^{-4}$ \cite{SCHR}. Since deuterium is destroyed by stars, and the…
We present new upper and lower bounds to the primordial abundances of deuterium and helium-3 based on observational data from the solar system and the interstellar medium. Independent of any model for the primordial production of the…
During its early evolution, the hot, dense Universe provided a laboratory for probing fundamental physics at high energies. By studying the relics from those early epochs, such as the light elements synthesized during primordial…
One of the still viable candidates for the dark matter is the so-called mirror matter. Its cosmological and astrophysical implications were widely studied in many aspects, pointing out the importance to go further with research and refine…
We discuss Big Bang Nucleosynthesis constraints on maximal $\nu_\mu\leftrightarrow\nu_s$ mixing. Vacuum $\nu_\mu\leftrightarrow\nu_s$ oscillation has been proposed as one possible explanation of the Super Kamiokande atmospheric neutrino…
The products of primordial nucleosynthesis and the cosmic microwave background (CMB) photons are relics from the early evolution of the Universe whose observations probe the standard model of cosmology and provide windows on new physics…
We present a simple method for determining the (correlated) uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. Our approach helps to clarify the…
We summarize the history, theory, observational status, and implications of big-bang nucleosynthesis.
We extend previous studies of big bang nucleosynthesis, with the assumption that ordinary matter and dark matter sectors are entangled through the number of degrees of freedom entering the Friedmann equations. This conjecture allows us to…
We re-examine neutrino oscillations in the early universe. Contrary to previous studies, we show that large neutrino asymmetries can arise due to oscillations between ordinary neutrinos and sterile neutrinos. This means that the Big Bang…