2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/92669This is the abstract of an invited contribution to be presented at the 9th International Conference on Squeezed States and Uncertainty Relations, ICSSUR '05, Besancon, France, May 2-6, 2005.1 page, 1 figureQuantum Physicstext