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The paper investigates solutions of the fractional hyperbolic diffusion equation in its most general form with two fractional derivatives of distinct orders. The solutions are given as spatial-temporal homogeneous and isotropic random…

Probability · Mathematics 2023-10-09 Nikolai Leonenko , Andriy Olenko , Jayme Vaz

We investigate the behavior of the time derivatives of the solution to a linear time-fractional, advection-diffusion-reaction equation, allowing space- and time-dependent coefficients as well as initial data that may have low regularity.…

Analysis of PDEs · Mathematics 2020-03-24 William McLean , Kassem Mustapha , Raed Ali , Omar M. Knio

We consider different types of processes obtained by composing Brownian motion $B(t)$, fractional Brownian motion $B_{H}(t)$ and Cauchy processes $% C(t)$ in different manners. We study also multidimensional iterated processes in…

Probability · Mathematics 2010-08-06 Luisa Beghin , Enzo Orsingher , Lyudmyla Sakhno

The fractional Fokker-Planck equation, which contains a variable diffusion coefficient, is discussed and solved. It corresponds to the L\'evy flights in a nonhomogeneous medium. For the case with the linear drift, the solution is stationary…

Statistical Mechanics · Physics 2009-06-09 Tomasz Srokowski

This article aims to investigate the semi-classical analog of the general Caputo-type diffusion equation with time-dependent diffusion coefficient associated with the discrete Schr\"{o}dinger operator,…

Analysis of PDEs · Mathematics 2024-07-19 Aparajita Dasgupta , Shyam Swarup Mondal , Michael Ruzhansky , Abhilash Tushir

We investigate the fractional Hardy-H\'enon equation with fractional Brownian noise $$ \partial_tu(t)+(-\Delta)^{\theta/2} u(t)=|x|^{-\gamma} |u(t)|^{p-1}u(t)+\mu \, \partial_t B^H(t), $$ where $\theta>0$, $p>1$, $\gamma\geq 0$, $\mu…

Analysis of PDEs · Mathematics 2025-06-12 R. Alessa , R. Al Subaie , M. Alwohaibi , M. Majdoub , E. Mliki

We introduce a fractional Fokker-Planck equation with a temporal power-law dependence on the drift force fields. For this case, the moments of the tracer from the force-force correlation in terms of the time-dependent drift force fields are…

Statistical Mechanics · Physics 2007-05-23 Kyungsik Kim , Y. S. Kong

We study the inverse random source problem for the time-space fractional diffusion equation driven by fractional Brownian motion with Hurst index $H\in(0,1)$. With the aid of a novel estimate, by using the operator approach we propose…

Probability · Mathematics 2021-06-03 Daxin Nie , Weihua Deng

In this paper, we propose a novel numerical scheme for solving time-fractional reaction-diffusion problems with Robin boundary conditions, where the time derivative is in the Caputo sense of order $\alpha\in(0,1)$. The existence and…

Numerical Analysis · Mathematics 2025-09-23 Qian Luo , Aiguo Xiao , Xiaoqiang Yan , Jingmin Xia

This article investigates several properties related to densities of solutions X to differential equations driven by a fractional Brownian motion with Hurst parameter H>1/4. We first determine conditions for strict positivity of the density…

Probability · Mathematics 2014-01-16 Fabrice Baudoin , Eulalia Nualart , Cheng Ouyang , Samy Tindel

This paper is about the fractional Schr\"odinger equation expressed in terms of the Caputo time-fractional and quantum Riesz-Feller space fractional derivatives for particle moving in a potential field. The cases of free particle (zero…

Mathematical Physics · Physics 2020-01-22 Saleh Baqer , Lyubomir Boyadjiev

We deal with some extensions of the space-fractional diffusion equation, which is satisfied by the density of a stable process (see Mainardi, Luchko, Pagnini (2001)): the first equation considered here is obtained by adding an exponential…

Probability · Mathematics 2016-01-08 Luisa Beghin

We investigate the solutions for a time dependent potential by considering two scenarios for the fractional Schr\"odinger equation. The first scenario analyzes the influence of the time dependent potential in the absence of the kinetic…

General Physics · Physics 2023-06-14 EC Gabrick , E Sayari , ASM de Castro , J Trobia , AM Batista , EK Lenzi

In this paper, we study both the direct and inverse random source problems associated with the multi-term time-fractional diffusion-wave equation driven by a fractional Brownian motion. Regarding the direct problem, the well-posedness is…

Analysis of PDEs · Mathematics 2023-11-03 Xiaoli Feng , Qiang Yao , Peijun Li , Xu Wang

We consider a system of multiscale stochastic differential equations whose slow component is drivenby a fractional Brownian motion with Hurst parameter H greater than 1/2. Under ergodic assumptions ensuring the applicability of the…

Probability · Mathematics 2025-12-10 Xue-Mei Li , Colin Piernot , Szymon Sobczak , Kexing Ying

We propose diffusion-like equations with time and space fractional derivatives of the distributed order for the kinetic description of anomalous diffusion and relaxation phenomena, whose diffusion exponent varies with time and which,…

Statistical Mechanics · Physics 2009-11-07 A. V. Chechkin , R. Gorenflo , I. M. Sokolov

We introduce a fractional Klein-Kramers equation which describes sub-ballistic superdiffusion in phase space in the presence of a space-dependent external force field. This equation defines the differential L{\'e}vy walk model whose…

Statistical Mechanics · Physics 2015-06-24 Ralf Metzler , Igor M. Sokolov

The diffusion system with time-fractional order derivative is of great importance mathematically due to the nonlocal property of the fractional order derivative, which can be applied to model the physical phenomena with memory effects. We…

Analysis of PDEs · Mathematics 2021-03-24 Mengmeng Zhang , Jijun Liu

We consider the radiative transport equation in which the time derivative is replaced by the Caputo derivative. Such fractional-order derivatives are related to anomalous transport and anomalous diffusion. In this paper we describe how the…

Mathematical Physics · Physics 2017-03-08 Manabu Machida

This paper is devoted to describing a linear diffusion problem involving fractional-in-time derivatives and self-adjoint integro-differential space operators posed in bounded domains. One main concern of our paper is to deal with singular…

Analysis of PDEs · Mathematics 2023-04-11 Hardy Chan , Juan Luis Vázquez , David Gómez-Castro