Coupled continuous-time random-walk: Pseudo diffusion with anisotropic scattering

Abstract

A generalization of pseudo-diffusion processes in media with anisotropic scattering, described by a coupled RW, is done by means of the CTRW theory. The behaviour of the probability distribution has been studied. A kind of phase breaking in such a behaviour arises as a function of the anisotropic parameter. Some examples, with different models for the waiting time density, are presented. In the limit of strong forward or backward scattering, we have a new way to analyze quasi-unidirectional or quasi-collapsed processes respectively.