A diagrammatic approach for open chaotic systems

A semiclassical diagrammatic approach is constructed for calculating correlation functions of observables in open chaotic systems with time reversal symmetry. The results are expressed in terms of classical correlation functions involving Wigner representations of the observables. The formalism is used to explain a recent microwave experiment on the 4-disk problem, and to characterize the two-point function of the photodissociation cross section of complex molecules.