Pseudo-orbits, stationary measures and metastability
نویسندگان
چکیده
We study random perturbations of multidimensional piecewise expanding maps. We characterize absolutely continuous stationary measures (acsm) of randomly perturbed dynamical systems in terms of pseudo-orbits linking the ergodic components of absolutely continuous invariant measures (acim) of the unperturbed system. We focus on those components, called least-elements, which attract pseudoorbits. We show that each least element is in a one-to-one correspondence with an ergodic acsm of the random system. Moreover our result permits to identify random perturbations that exhibit a metastable behavior.
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