2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/55937Classical and quantum gravitational instabilities, can, respectively, inflate and warm up a primordial Universe satisfying a superstring-motivated principle of "Asymptotic Past Triviality". A physically viable big bang is thus generated without invoking either large fine-tunings or a long period of post-big bang inflation. Properties of the pre-bangian Universe can be probed through its observable relics, which include: i) a (possibly observable) stochastic gravitational-wave background; ii) a (possible) new mechanism for seeding the galactic magnetic fields; iii) a (possible) new source of large-scale structure and CMB anisotropy.Latex file, 17 pages, 5 figures, Based on two recent talks, References updatedHigh Energy Physics - Theorytext