2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/108785In the case of a single point interaction we improve, by different techniques, the existence theorem for the unitary evolution generated by a Schrödinger operator with moving point interactions obtained by Dell'Antonio, Figari and Teta.Revised version, to appear in Proc. Am. Math. SocMathematical PhysicsQuantum Physicstext