Neutrinos in cosmology: current bounds and new physics scenarios

by Dr Ninetta Saviano (IPPP Durham, UK)

Thursday 29 Jan 2015, 11:15 → 12:15 Europe/Berlin

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Relic neutrinos play an important role in the evolution of the Universe, having a remarkable impact on the cosmological observables. Notably, Big Bang Nucleosynthesis (BBN), Cosmic Microwave Background (CMB) and Structure Formation (LSS) data represent powerful probes for the neutrino properties. In this talk we show how these cosmological data can be used to bound the absolute scale of neutrino masses and the effective number of neutrino species ($N_{\rm eff}$). We also discuss the cosmological impact of sterile neutrinos that would act as a portal towards new physics scenarios. In particular eV sterile neutrinos, suggested by laboratory anomalies, could modify the standard framework requiring large primordial neutrino asymmetries or secret neutrino self-interactions to accommodate these particles with cosmological observations.