RT info:eu-repo/semantics/article T1 Non-Atkinson Perturbations of Nonautonomous Linear Hamiltonian Systems: Exponential Dichotomy and Nonoscillation A1 Núñez Jiménez, María del Carmen A1 Obaya, Rafael AB We analyze the presence of exponential dichotomy (ED) and of global existence ofWeyl functions M± for one-parametric families of finite-dimensional nonautonomous linearHamiltonian systems defined along the orbits of a compact metric space, which are perturbedfrom an initial one in a direction which does not satisfy the classical Atkinson condition:either they do not have ED for any value of the parameter; or they have it for at least all thenonreal values, in which case theWeyl functions exist and are Herglotz. When the parametervaries in the real line, and if the unperturbed family satisfies the properties of exponentialdichotomy and global existence of M+, then these two properties persist in a neighborhoodof 0 which agrees either with the whole real line or with an open negative half-line; and inthis last case, the ED fails at the right end value. The properties of ED and of global existenceof M+ are fundamental to guarantee the solvability of classical minimization problems givenby linear–quadratic control processes. PB Springer SN 1040-7294 YR 2018 FD 2018 LK http://uvadoc.uva.es/handle/10324/41602 UL http://uvadoc.uva.es/handle/10324/41602 LA spa NO Journal of Dynamics and Differential Equations 31 (3) (2019), 1397–1426 DS UVaDOC RD 02-may-2024