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Related papers: CTRW Pathways to the Fractional Diffusion Equation

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We consider the continuous time random walk model (CTRW) of tracer's motion in porous medium flows based on the experimentally determined distributions of pore velocity and pore size reported in Holzner et al. Phys. Rev. E 92, 013015…

Statistical Mechanics · Physics 2017-05-31 Itzhak Fouxon , Markus Holzner

Continuous time random walks (CTRW) on finite arbitrarily inhomogeneous chains are studied. By introducing a technique of counting all possible trajectories, we derive closed-form solutions in Laplace space for the Green's function and for…

Soft Condensed Matter · Physics 2007-05-23 Ophir Flomenbom , Joseph Klafter

The continuous time random walk (CTRW) underlies many fundamental processes in non-equilibrium statistical physics. When the jump length of CTRW obeys a power-law distribution, its corresponding Fokker-Planck equation has space fractional…

Numerical Analysis · Mathematics 2017-06-28 Yanyan Yu , Weihua Deng , Yujiang Wu

Continuous Time Random Walks (CTRWs) are jump processes with random waiting times between jumps. We study scaling limits for CTRWs where the distribution of jumps and waiting times is coupled and varies in space and time. Such processes…

Probability · Mathematics 2015-01-06 Peter Straka

Continuous-time random walks (CTRW) play important role in understanding of a wide range of phenomena. However, most theoretical studies of these models concentrate only on stationary-state dynamics. We present a new theoretical approach,…

Statistical Mechanics · Physics 2015-05-14 Anatoly B. Kolomeisky

A continuous time random walk (CTRW) model with waiting times following the Levy-stable distribution with exponential cut-off in equilibrium is a simple theoretical model giving rise to normal, yet non-Gaussian diffusion. The distribution…

Data Analysis, Statistics and Probability · Physics 2017-05-31 S. M. J. Khadem , I. M. Sokolov

We consider the linear response of systems modelled by continuous-time random walks (CTRW) and by fractional Fokker-Planck equations under the influence of time-dependent external fields. We calculate the corresponding response functions…

Statistical Mechanics · Physics 2009-11-07 I. M. Sokolov , A. Blumen , J. Klafter

Initially developed in the framework of quantum stochastic calculus, the main equations of quantum stochastic filtering were later on derived as the limits of Markov models of discrete measurements under appropriate scaling. In many…

Mathematical Physics · Physics 2020-08-18 Vassili N. Kolokoltsov

The fractional diffusion-wave equation (FDWE) is a recent generalization of diffusion and wave equations via time and space fractional derivatives. The equation underlies Levy random walk and fractional Brownian motion and is foremost…

Mathematical Physics · Physics 2007-05-23 W. Chen , S. Holm

Continuous time random walk (CTRW) subdiffusion along with the associated fractional Fokker-Planck equation (FFPE) is traditionally based on the premise of random clock with divergent mean period. This work considers an alternative CTRW and…

Statistical Mechanics · Physics 2014-09-24 Igor Goychuk

The diffusion equation and its time-fractional counterpart can be obtained via the diffusion limit of continuous-time random walks with exponential and heavy-tailed waiting time distributions. The space dependent variable-order…

Statistical Mechanics · Physics 2025-10-24 Christopher N. Angstmann , Daniel S. Han , Bruce I. Henry , Boris Z. Huang , Zhuang Xu

The continuous time random walk model plays an important role in modeling of so called anomalous diffusion behaviour. One of the specific property of such model are constant time periods visible in trajectory. In the continuous time random…

Data Analysis, Statistics and Probability · Physics 2017-01-04 Rafał Połoczański , Agnieszka Wyłomańska , Janusz Gajda , Monika Maciejewska , Andrzej Szczurek

The Continuous Time Random Walk (CTRW) formalism is used to model the non-Poisson relaxation of a system response to perturbation. Two mechanisms to perturb the system are analyzed: a first in which the perturbation, seen as a potential…

Disordered Systems and Neural Networks · Physics 2009-11-13 Gerardo Aquino , Paolo Grgolini , Bruce J. West

The purpose of this tutorial is to introduce the main concepts behind normal and anomalous diffusion. Starting from simple, but well known experiments, a series of mathematical modeling tools are introduced, and the relation between them is…

Chaotic Dynamics · Physics 2008-05-06 Loukas Vlahos , Heinz Isliker , Yannis Kominis , Kyriakos Hizanidis

Fractional, anomalous diffusion in space-periodic potentials is investigated. The analytical solution for the effective, fractional diffusion coefficient in an arbitrary periodic potential is obtained in closed form in terms of two…

Statistical Mechanics · Physics 2021-02-02 E. Heinsalu , M. Patriarca , I. Goychuk , P. Hanggi

We present the path integral formulation of a broad class of generalized diffusion processes. Employing the path integral we derive exact expressions for the path probability densities and joint probability distributions for the class of…

Statistical Mechanics · Physics 2011-10-27 Rudolf Friedrich , Stephan Eule

We show the asymptotic long-time equivalence of a generic power law waiting time distribution to the Mittag-Leffler waiting time distribution, characteristic for a time fractional CTRW. This asymptotic equivalence is effected by a…

Statistical Mechanics · Physics 2008-05-18 Rudolf Gorenflo , Francesco Mainardi

In this paper we study controlled continuous time random walks (CTRWs) and heuristically derive pay-off function dynamic programming (DP) equations which turn in the limit of standard scaling to fractional Hamilton Jacobi Bellman type…

Optimization and Control · Mathematics 2012-04-05 V. Kolokoltsov , M. Veretennikova

Continuous time random walks (CTRWs) are versatile models for anomalous diffusion processes that have found widespread application in the quantitative sciences. Their scaling limits are typically non-Markovian, and the computation of their…

Probability · Mathematics 2014-07-25 Mark M. Meerschaert , Peter Straka

The concept of continuous-time random walks (CTRW) is a generalization of ordinary random walk models, and it is a powerful tool for investigating a broad spectrum of phenomena in natural, engineering, social and economic sciences.…

Statistical Mechanics · Physics 2015-06-12 Hamid Teimouri , Anatoly B. Kolomeisky