2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/95882We study the possibility of revealing a weak coherent force by using a pendular mirror as a probe, and coupling this to a radiation field, which acts as the meter, in a cavityless configuration. We determine the sensitivity of such a scheme and show that the use of an entangled meter state greatly improves the ultimate detection limit. We also compare this scheme with that involving an optical cavity.4 pages, RevTex file, 2 eps figures, provisionally accepted by Phys. Rev.AQuantum Physicstext