2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44997Given the conservation of baryon number as well as electron and muon numbers, all present data can be explained without the need of a conserved quantum number for the tau lepton and its neutrino. A supersymmetric extension of the standard model naturally allows for such a scenario. One consequence is that the tau neutrino becomes the lightest supersymmetric particle.6 pages, UCRHEP-T117 and MAD/PH/799, to appear in Proc. of the Second Talinn Neutrino Symposium, Lohusalu, Estonia, Oct 1993High Energy Physics - Phenomenologytext