  It is proved that true Goldstone bosons develop coherent fields whenever the
associated charges of the matter particles are not conserved in a macroscopic
scale. The sources of the Goldstone fields are the time rates of quantum number
violation. The case of neutrino flavour oscillations is studied with
application to Supernovae. It is shown that if the Lepton numbers break at the
Fermi scale, the neutrino potentials and oscillation patterns change in the
periods of largest neutrino fluxes. In this way, electron anti-neutrino to muon
anti-neutrino oscillations may occur in the first instants of neutrino
emission.

High Energy Physics - Phenomenology;High Energy Physics - Theory