2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/141440We study almost periodic orbits of quantum systems and prove that for periodic time-dependent Hamiltonians an orbit is almost periodic if, and only if, it is precompact. In the case of quasiperiodic time-dependence we present an example of a precompact orbit that is not almost periodic. Finally we discuss some simple conditions assuring dynamical stability for nonautonomous quantum system.Reports Math Phys; 18 pagesMathematical Physics81Q10; 11B; 47B99text