2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67075We apply the ``black box'' scattering theory to problems in control theory and in high energy eigenvalue scarring.24 pages, 6 figures, precisions added to some of the proofs, typos fixedAnalysis of PDEsOptimization and ControlControl in the presence of a black boxtext