The status of primordial nucleosynthesis featuring Cyril Pitrou (Institut d'Astrophysique de Paris, France)

Hosted by: Steffen Turkat (TU Dresden)

Abstract: Primordial nucleosynthesis or Big-Bang Nucleosynthesis (BBN) happens during the first 300 seconds of our Universe. It is one of the three evidences for the big-bang model, together with the cosmological expansion and the Cosmic Microwave Background (CMB). As primordial abundances of light elements are measured with percent-level precision, mild tensions arise with the theoretical predictions of the standard cosmological model. This calls for improved measurements of the key nuclear rates which are involved in these predictions. In addition, since the physics at play crucially depends on neutrino physics, BBN is also a powerful tool to constrain neutrino properties in the early universe. I will summarize how neutrino asymmetries, arising from non-vanishing chemical potentials, will be constrained by BBN combined with future CMB experiments.