2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/54658We discuss the statistical-mechanical entropy of black hole calculated according to 't Hooft. It is argued that in presence of horizon the statistical mechanics of quantum fields depends on their UV behavior. The ``brick wall'' model was shown to provide a correct description when the ``brick wall'' parameter is less than any UV cut-off.4 pages, latex. Invited talk at 2nd International Sakharov Conference on Physics, Moscow, Russia, 20-23 May 1996High Energy Physics - Theorytext