Showing 1 - 10 of 21
We study normal and anomalous diffusion processes with initial conditions of the broad Lévy type, i.e., with such initial conditions which, per se, exhibit a diverging variance. In the force-free case, the behaviour of the associated probability density function features distinct shoulders...
Persistent link: https://www.econbiz.de/10010589809
We discuss two models for the description of anomalous diffusion, these being the continuous time random walk scheme, and fractional diffusion equations. We show their interrelations, and combine both approaches for the description of anomalous transport in constant external velocity and force...
Persistent link: https://www.econbiz.de/10010664906
Fractional moments have been investigated by many authors to represent the density of univariate and bivariate random variables in different contexts. Fractional moments are indeed important when the density of the random variable has inverse power-law tails and, consequently, it lacks integer...
Persistent link: https://www.econbiz.de/10010590155
We investigate the connection of the Cattaneo equation and the stochastic continuous time random walk (CTRW) theory. We show that the velocity model in a CTRW scheme is suited to derive the standard Cattaneo equation, and allows, in principle, for a generalisation to anomalous transport. As a...
Persistent link: https://www.econbiz.de/10010664925
We investigate the solution of space–time fractional diffusion equations with a generalized Riemann–Liouville time fractional derivative and Riesz–Feller space fractional derivative. The Laplace and Fourier transform methods are applied to solve the proposed fractional diffusion equation....
Persistent link: https://www.econbiz.de/10011060629
In recent years the phenomenon of anomalous diffusion has attracted more and more attention. One of the main impulses was initiated by de Gennes' idea of the “ant in the labyrinth”. Several authors presented asymptotic probability density functions for the location of a random walker on a...
Persistent link: https://www.econbiz.de/10011062633
We study the temporal ‘on-and-off’ structure of the recently introduced nonlinear Shot Noise model [I. Eliazar, J. Klafter, PNAS 102 (2005) 13779; I. Eliazar, J. Klafter, Nonlinear shot noise: Lévy, Noah, & Joseph, Physica A (2006), to appear], in which: (i) shots of random magnitudes...
Persistent link: https://www.econbiz.de/10010589146
In the nonlinear shot noise system-model shots’ statistics are governed by general Poisson processes, and shots’ decay-dynamics are governed by general nonlinear differential equations. In this research we consider a nonlinear shot noise system and explore the process tracking, along time,...
Persistent link: https://www.econbiz.de/10010590832
We present a universal mechanism for the temporal generation of power-law distributions with arbitrary integer-valued exponents.
Persistent link: https://www.econbiz.de/10010872766
We explore the correlation-structure of a large class of random processes, driven by non-Gaussian Lévy noise sources with possibly infinite variances. Examples of such processes include Lévy motions, Lévy-driven Ornstein–Uhlenbeck motions, Lévy-driven moving-average processes, fractional...
Persistent link: https://www.econbiz.de/10010874022