2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56110Invited talk at the conference "Fundamental Interactions: From Symmetries to Black Holes" in honor of Francois Englert, 24 - 27 March, Universite Libre de Bruxelles, Belgium14 pagesHigh Energy Physics - TheoryOn Hidden Symmetries in d=11 Supergravity and Beyondtext