Abstract
The author has studied diffusion in a disordered network in which the transition rates of the bonds of the network are dependent on time. He solves the problem by making an effective-medium approximation (EMA) and find that if the values of the transition rates vary between two values with a relaxation time tR, and if Wm( lambda ) is the Laplace-transformed solution of the problem in the limit tR= infinity , then Wm( lambda +tR-1) is the solution of the dynamic problem for any value of tR. The EMA also predicts that the percolation threshold of the system is zero if tR not=0. Some applications of this problem are also discussed.