2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/35977The Mixmaster or Bianchi IX cosmological model has become one of the archetypal settings for studying gravitational dynamics. The past decade has seen a vigourous debate about whether or not the Mixmaster's dynamics is chaotic. In this talk we review our recent work in uncovering a chaotic invariant set of orbits in the Mixmaster phase space, and how we used this discovery to prove the dynamics is chaotic.3 pages, 2 figures. To appear in the proceedings of the Eighth Marcel Grossmann Meeting, Jerusalem, June 1997 (WSP)General Relativity and Quantum Cosmologytext