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Related papers: Levy Flights in Inhomogeneous Media

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A nonlinear PDE featuring flux limitation effects together with those of the porous media equation (nonlinear Fokker-Planck) is presented in this paper. We analyze the balance of such diverse effects through the study of the existence and…

Analysis of PDEs · Mathematics 2018-04-03 J. Calvo , J. Campos , V. Caselles , O. Sánchez , J. Soler

A global picture of a random particle movement is given by the convex hull of the visited points. We obtained numerically the probability distributions of the volume and surface of the convex hulls of a selection of three types of…

Statistical Mechanics · Physics 2018-07-04 Hendrik Schawe , Alexander K. Hartmann , Satya N. Majumdar

The purpose of this paper is to implement a random death process into a persistent random walk model which produces subballistic superdiffusion (L\'{e}vy walk). We develop a Markovian model of cell motility with the extra residence variable…

Statistical Mechanics · Physics 2015-05-20 Sergei Fedotov , Abby Tan , Andrey Zubarev

Advective trapping occurs when solute enters low velocity zones in heterogeneous porous media. Classical local modeling approaches combine the impact of slow advection and diffusion into a hydrodynamic dispersion coefficient and many…

Fluid Dynamics · Physics 2020-12-02 Juan J. Hidalgo , Insa Neuweiler , Marco Dentz

The use of reaction-diffusion models rests on the key assumption that the underlying diffusive process is Gaussian. However, a growing number of studies have pointed out the prevalence of anomalous diffusion, and there is a need to…

Pattern Formation and Solitons · Physics 2009-11-07 D. del-Castillo-Negrete , B. A. Carreras , V. E. Lynch

Recent experiments (G. Ariel, et al., Nature Comm. 6, 8396 (2015)) revealed an intriguing behavior of swarming bacteria: they fundamentally change their collective motion from simple diffusion into a superdiffusive L\'{e}vy walk dynamics.…

Statistical Mechanics · Physics 2017-04-05 Sergei Fedotov , Nickolay Korabel

We consider the time evolution of two-dimensional Levy flights in a finite area with periodic boundary conditions. From simulations we show that the fractal path dimension d_f and thus the degree of area coverage grows in time until it…

Statistical Mechanics · Physics 2015-06-12 Mahsa Vahabi , Johannes H. P. Schulz , Babak Shokri , Ralf Metzler

We compute the average shape of trajectories of some one--dimensional stochastic processes x(t) in the (t,x) plane during an excursion, i.e. between two successive returns to a reference value, finding that it obeys a scaling form. For…

Statistical Mechanics · Physics 2009-11-10 Francesca Colaiori , Andrea Baldassarri , Claudio Castellano

We introduce a persistent random walk model for the stochastic transport of particles involving self-reinforcement and a rest state with Mittag-Leffler distributed residence times. The model involves a system of hyperbolic partial…

Statistical Mechanics · Physics 2021-11-16 Daniel Han , Dmitri V. Alexandrov , Anna Gavrilova , Sergei Fedotov

Noise induced jumping between meta-stable states in a potential depends on the structure of the noise. For an $\alpha$-stable noise, jumping triggered by single extreme events contributes to the transition probability. This is also called…

Data Analysis, Statistics and Probability · Physics 2009-10-31 P. D. Ditlevsen

Non-Gaussian L\'evy noises are present in many models for understanding underlining principles of physics, finance, biology and more. In this work, we consider the Fokker-Planck equation(FPE) due to one-dimensional asymmetric L\'evy motion,…

Dynamical Systems · Mathematics 2018-03-05 Xiao Wang , Wenpeng Shang , Xiaofan Li , Jinqiao Duan , Yanghong Huang

We present a probabilistic theory of random walks in turbid media with non-scattering regions. It is shown that important characteristics such as diffusion constants, average step lengths, crossing statistics and void spacings can be…

Disordered Systems and Neural Networks · Physics 2013-02-18 Tomas Svensson , Kevin Vynck , Marco Grisi , Romolo Savo , Matteo Burresi , Diederik S. Wiersma

The phenomena of subdiffusion are widely observed in physical and biological systems. To investigate the effects of external potentials, say, harmonic potential, linear potential, and time dependent force, we study the subdiffusion…

Statistical Mechanics · Physics 2019-04-24 Yao Chen , Xudong Wang , Weihua Deng

The Levy diffusion processes are a form of non ordinary statistical mechanics resting, however, on the conventional Markov property. As a consequence of this, their dynamic derivation is possible provided that (i) a source of randomness is…

Statistical Mechanics · Physics 2016-08-31 Mauro Bologna , Paolo Grigolini , Juri Riccardi

Stochastic differential equations with Levy motion arise the mathematical models for various phenomenon in geophysical and biochemical sciences. The Fokker Planck equation for such a stochastic differential equations is a nonlocal partial…

Analysis of PDEs · Mathematics 2020-06-08 Li Lin

Mathematical models based on probability density functions (PDF) have been extensively used in hydrology and subsurface flow problems, to describe the uncertainty in porous media properties (e.g., permeability modelled as random field).…

Fluid Dynamics · Physics 2020-06-01 Matteo Icardi , Marco Dentz

We consider a persistent random walk on an inhomogeneous environment where the reflection probability depends only on the distance from the origin. Such an environment is the result of an average over all realizations of disorder of a…

Statistical Mechanics · Physics 2020-10-20 Mattia Radice , Manuele Onofri , Roberto Artuso , Giampaolo Cristadoro

Anomalous diffusion, manifest as a nonlinear temporal evolution of the position mean square displacement, and/or non-Gaussian features of the position statistics, is prevalent in biological transport processes. Likewise, collective behavior…

Statistical Mechanics · Physics 2020-04-01 Andrea Cairoli , Chiu Fan Lee

We study a random walk on a point process given by an ordered array of points $(\omega_k, \, k \in \mathbb{Z})$ on the real line. The distances $\omega_{k+1} - \omega_k$ are i.i.d. random variables in the domain of attraction of a…

Probability · Mathematics 2021-05-05 Samuele Stivanello , Gianmarco Bet , Alessandra Bianchi , Marco Lenci , Elena Magnanini

We study the distribution of first passage time (FPT) in Levy type of anomalous diffusion. Using recently formulated fractional Fokker-Planck equation we obtain three results. (1) We derive an explicit expression for the FPT distribution in…

Statistical Mechanics · Physics 2009-11-07 Govindan Rangarajan , Mingzhou Ding