ISSN:
1572-9613
Keywords:
Random Walk
;
Master Equation
;
Poisson Noise
;
Disordered Systems
;
Diffusion
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Exact solutions are given for a variety of models of random walks in a chain with time-dependent disorder. Dynamic disorder is modeled by white Poisson noise. Models with site-independent (global) and site-dependent (local) disorder are considered. Results are described in terms of an affective random walk in a nondisordered medium. In the cases of global disorder the effective random walk contains multistep transitions, so that the continuous limit is not a diffusion process. In the cases of local disorder the effective process is equivalent to usual random walk in the absence of disorder but with slower diffusion. Difficulties associated with the continuous-limit representation of random walk in a disordered chain are discussed. In particular, we consider explicit cases in which taking the continuous limit and averaging over disorder sources do not commute.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01041077
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