2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193496Dark matter is usually distinguished from ordinary matter by an odd-even parity, i.e. the discrete symmetry Z_2. The new idea of Z_3 dark matter is proposed with a special application to generating radiative Majorana neutrino masses in two-loop order.expanded (9 pages, 2 figures), 2 references addedHigh Energy Physics - Phenomenologytext