2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56141After discussing some old (and not-so-old) entropy bounds both for isolated systems and in cosmology, I will argue in favour of a "Hubble entropy bound" holding in the latter context. I will then apply this bound to recent developments in string cosmology, show that it is naturally saturated throughout pre-big bang inflation, and claim that its fulfilment at later times has interesting implications for the exit problem of string cosmology.Latex file, 11 pages, 3 figures, Talk given in honour of F. Englert, Brussels, March 1999High Energy Physics - Theorytext