2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/213252We discuss several numerical conditions for families of projective varieties or variations of Hodge structures.Survey, 25 pages 2nd. Version: Part of the last chapter was reformulated and some typos were correctedAlgebraic GeometryComplex Variables14G35 (Primary) 14K10, 14D05, 14D07, 14J60, 32G15text