2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44039A possibility of existence of ultra-heavy (quasi)stable particles, mechanisms leading to their large life-time, their production in the early universe, and cosmological manifestations are reviewed.14 pages, presented at INFN Eloisatron Project, 44th Workshop, QCD at Cosmic Energies, August 29 - September 5, 2004, Erice, ItalyHigh Energy Physics - Phenomenologytext