2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/8539We are told that we are living in a Golden Age of Astronomy. Cosmological Parameters are found with un precedented accuracy. Yet, the known form of matter forms only a small fraction of the total energy density of the universe. Also, a mysterious dark energy dominates the universe and causes acceleration in the rate of expansion.To be published in the Proceedings of the Interantional Conference on COSMOLOGY;Facts and Problems (College de France, Paris, June 8-11, 2004)Astrophysicstext