Scattering from spatially localized chaotic and disordered systems

A version of scattering theory that was developed many years ago to treat n uclear scattering processes, has provided a powerful tool to study universa lity in scattering processes involving open quantum systems with underlying classically chaotic dynamics. Recently, it has been used to make random ma trix theory predictions concerning the statistical properties of scattering resonances in mesoscopic electron waveguides and electromagnetic waveguide s. We provide a simple derivation of this scattering theory and we compare its predictions to those obtained from an exactly solvable scattering model ; and we use it to study the scattering of a particle wave from a random po tential. This methods may prove useful in distinguishing the effects of cha os from the effects of disorder in real scattering processes.