Neutrinos in Cosmology

Understand

Neutrinos are the least known particle in the Standard Model of elementary particle physics.

• They play a crucial role in cosmology, governing the universe's evolution and shaping the large-scale structures we observe today.
• In this chapter, we review crucial topics in neutrino cosmology, such as the neutrino decoupling process in the very early universe.
• We shall also revisit the current constraints on the number of effective relativistic degrees of freedom and the departures from its standard expectation of 3.