Diffusion and relaxation controlled by tempered -stable processes
نویسندگان
چکیده
We derive general properties of anomalous diffusion and nonexponential relaxation from the theory of tempered -stable processes. The tempering results in the existence of all moments of operational time. The subordination by the inverse tempered -stable process provides diffusion relaxation that occupies an intermediate place between subdiffusion Cole-Cole law and normal diffusion exponential law . Here we obtain explicitly the Fokker-Planck equation and the Cole-Davidson relaxation function. This model includes subdiffusion as a particular case.
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تاریخ انتشار 2008