Neutrinos in Astrophysics and Cosmology: Theoretical Advanced Study Institute (TASI) 2020 Lectures

Understand

I introduce the consequences of neutrino mass and mixing in the dense environments of the early Universe and in astrophysical environments.

• Thermal and matter effects are reviewed in the context of a two-neutrino formalism, with methods of extension to multiple neutrinos.
• The observed large neutrino mixing angles place the strongest constraint on cosmological lepton (or neutrino) asymmetries, while new sterile neutrinos provide a wealth of possible new physics, including lepton asymmetry generation as well as candidates for dark matter.
• I also review cosmic microwave background and large-scale structure constraints on neutrino mass and energy density.