2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/93124This is a writeup of a talk given at the Oskar Klein Centenery Symposium, Stockholm, September 19-21, 1994. It is an essay on the black hole information paradox and its connection with thermodynamics and the foundations of quantum mechanics.17 pages, LatexQuantum Physicstext