NEUTRINO QUANTUM KINETICS

This project aims at solving one of the most urgent riddles in particle astrophysics: how neutrinos affect the physics of spectacular cosmic fireworks in the death of massive stars as core-collapse supernova explosions and in the merger of two neutron stars or a neutron star and a black hole. Neutrinos are feebly interacting particles copiously produced in these dense sources. Neutrinos exist in three different kinds, or flavors, and have the fascinating property of changing their flavor while propagating (flavor conversion). Because of the high density of neutrinos in the core of supernovae or compact binary mergers, flavor conversion becomes a non-linear phenomenon, whose understanding is quite preliminary. In particular, a fully multi-dimensional solution of quantum transport of neutrinos is lacking, halting any assessment of the implications and phenomenology of flavor mixing. I propose the ambitious ANET (Advanced NEutrino Transport) project to: 1. develop an innovative approach to tackle neutrino transport in the presence of flavor conversion in multi-dimensions including all the relevant microphysics, for the first time; 2. pioneer a conclusive evaluation of the yet poorly explored impact of neutrinos in dense sources; 3. unravel the relevance of neutrino mixing with respect to other astrophysical unknowns. Numerical simulations buttressed by analytic diagnostic methods will be employed to radically advance our understanding. ANET promises to have profound implications on fundamental physics, the origin of the heavy elements, as well as our comprehension of the behavior of matter at extreme densities and the physics of neutrino-dense sources.