“…The self-interaction term from neutrino-neutrino scattering generates nonlinear effects that only recently have been studied in detail in the context of supernovae [7,25,34,40,41,42,43,44,45,46,47,48,49]. The character of the neutrino conversion is roughly determined by the relative size of the different frequencies ω ji , ω e , and ω ν .…”