2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184551Krauss and Wilczek have shown that an unbroken discrete gauge symmetry is respected by gravitationally mediated processes. This has led to a search for such a symmetry compatible with the standard model or MSSM that would protect protons from gravitationally mediated decay in a universe with a low scale for quantum gravity (large extra dimensions). The fact that the discrete symmetry must remain unbroken and have a gauge origin puts important restrictions on the space of possible discrete symmetries.8 pages, uses JHEP3.clsHigh Energy Physics - Theorytext