Synchronized neutrino oscillations from self-interaction and associated applications

A recent revival of interest in synchronized oscillations due to neutrino-neutrino forward scattering in dense gases has led to two interesting applications with notable outcomes: (i) cosmological bounds on neutrino-antineutrino asymmetries are improved owing to flavor equilibration prior to the onset of big bang nucleosynthesis, and (ii) a neutron-rich environment required for r-process nucleosynthesis is shown to be always maintained in a supernova hot bubble irrespective of flavor oscillations, contrary to results from previous studies. I present in this talk a pedagogical review of these works.