2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/198465We consider particle oscillations and their damping in second-quantized form. We find that the damping or "decoherence" may be described by a Boltzmann-like collision integral with "non-abelian blocking factors" (fermions). Earlier results are generalized in that the momentum degrees of freedom are included and that the mixing equations become intrinsically non-linear at high densities.12 pages, no figures, PLAIN-TeX, Preprint MPI-Ph/92-65High Energy Physics - PhenomenologyAstrophysicstext