2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140401A Bell inequality defined for a specific experimental configuration can always be extended to a situation involving more observers, measurement settings or measurement outcomes. In this article, such "liftings" of Bell inequalities are studied. It is shown that if the original inequality defines a facet of the polytope of local joint outcome probabilities then the lifted one also defines a facet of the more complex polytope.Revtex, 8 pages. v2: minor revisionsQuantum Physicstext