Vacuum energy for a massive Dirac neutrino propagating in a neutron medium- art. no. 125010

We calculate the energy acquired by the vacuum due to both a massless and m assive Dirac neutrino propagating in an external neutron field, utilizing t he quantum field theoretic approach of Schwinger. This method computes the vacuum energy to all orders in the coupling, using the interaction Hamilton ian for a neutrino in the presence of an external background of neutrons. T o verify our results, we develop heuristic arguments to compute the energy of the neutrino condensate arisings from a neutron-induced chiral potential well. The results for the massive case are new, and are discussed in some detail.