Neutrino Kinetics in Neutron Star Mergers

Following a neutron star merger, neutrinos are the primary means of cooling the resulting accretion disk and remnant compact object, they drive outflows, and they determine the abundances of elements formed in the ejecta. State-of-the-art numerical relativity simulations of these mergers employ a variety of methods for accounting for this radiation transport at differing levels of cost, complexity, and accuracy. I will briefly justify the local interaction approximation that is the basis for all current methods, describe the place each class of methods has in current science goals, and divine the future needs of relativistic radiation transport. Furthermore, I will introduce current efforts to understand the effects of the quantum nature of neutrino flavor and spin, including numerical methods, microscopic instabilities, and attempts at parameterizing sub-grid models of neutrino flavor transformation for inclusion in global numerical relativity simulations.