2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44773If a fermion is travelling through a medium, it can have matter-induced magnetic and electric dipole moments. These contributions conserve chirality, and can be non-vanishing even for a Majorana neutrino. Several implications for neutrino physics are discussed.(Talk given at the `Rencontres de Moriond', to appear in the Proceedings.) 4 pages LATEX, Report number DOE-ER 40757-007, CPP-93-07High Energy Physics - Phenomenologytext