English
Related papers

Related papers: The Inverse first passage time method for a two di…

200 papers

A study of time homogeneous, real valued Markov processes with a special property and a non-atomic initial distribution is provided. The new notion of a function of evolution of distribution which determines the dependency between one…

Probability · Mathematics 2022-07-04 Tomasz Bielecki , Jacek Jakubowski , Maciej Wiśniewolski

In this paper we want to propose practical numerical methods to solve a class of initial-boundary problem of time-space fractional convection-diffusion equations (TSFCDEs). To start with, an implicit difference method based on two-sided…

Numerical Analysis · Mathematics 2021-07-26 Xian-Ming Gu , Ting-Zhu Huang , Cui-Cui Ji , Bruno Carpentieri , Anatoly A. Alikhanov

Time fractional advection-dispersion equations arise as generalizations of classical integer order advection-dispersion equations and are increasingly used to model fluid flow problems through porous media. In this paper we develop an…

Numerical Analysis · Mathematics 2019-05-16 Carlos E. Mejía , Alejandro Piedrahita

Let $W$ be a standard Brownian motion with $W_0 = 0$ and let $b\colon[0,\infty) \to \mathbb{R}$ be a continuous function with $b(0) > 0$. In this article, we look at the classical First Passage Time (FPT) problem, i.e., the question of…

Probability · Mathematics 2024-04-26 Sören Christensen , Oskar Hallmann , Maike Klein

In this work, we propose a novel methodology for robustly estimating particle size distributions from optical scattering measurements using constrained Gaussian process regression. The estimation of particle size distributions is commonly…

Machine Learning · Statistics 2025-07-08 Fahime Seyedheydari , Mahdi Nasiri , Marcin Mińkowski , Simo Särkkä

We address the now classical problem of a diffusion process that crosses over from a ballistic behavior at short times to a fractional diffusion (sub- or super-diffusion) at longer times. Using the standard non-Markovian diffusion equation…

Statistical Mechanics · Physics 2015-05-14 Valery Ilyin , Itamar Procaccia , Anatoly Zagorodny

The time of the first occurrence of a threshold crossing event in a stochastic process, known as the first passage time, is of interest in many areas of sciences and engineering. Conventionally, there is an implicit assumption that the…

Statistical Mechanics · Physics 2021-11-24 Aanjaneya Kumar , Aniket Zodage , M. S. Santhanam

The first passage time for a single diffusing particle has been studied extensively, but the first passage time of a system of many diffusing particles, as is often the case in physical systems, has received little attention until recently.…

Statistical Mechanics · Physics 2024-11-22 Jacob B. Hass , Ivan Corwin , Eric I. Corwin

A standard inverse problem is to determine a source which is supported in an unknown domain $D$ from external boundary measurements. Here we consider the case of a time-dependent situation where the source is equal to unity in an unknown…

Numerical Analysis · Mathematics 2019-04-08 William Rundell , Zhidong Zhang

We consider the problem of computing first-passage time distributions for reaction processes modelled by master equations. We show that this generally intractable class of problems is equivalent to a sequential Bayesian inference problem…

Computational Physics · Physics 2017-11-29 David Schnoerr , Botond Cseke , Ramon Grima , Guido Sanguinetti

We study the first passage time (FPT) problem for biased continuous time random walks. Using the recently formulated framework of fractional Fokker-Planck equations, we obtain the Laplace transform of the FPT density function when the bias…

Statistical Mechanics · Physics 2007-05-23 Govindan Rangarajan , Mingzhou Ding

Regime switching processes have proved to be indispensable in the modeling of various phenomena, allowing model parameters that traditionally were considered to be constant to fluctuate in a Markovian manner in line with empirical findings.…

Probability · Mathematics 2019-04-03 Filip Lindskog , Abhishek Pal Majumder

A mathematical description of the refractoriness period in neuronal diffusion modeling is given and its moments are explicitly obtained in a form that is suitable for quantitative evaluations. Then, for the Wiener, Ornstein-Uhlenbeck and…

Probability · Mathematics 2007-05-23 A. Buonocore , G. Esposito , V. Giorno , C. Valerio

The time-fractional diffusion-wave equation is revisited, where the time derivative is of order $2 \nu$ and $0 < \nu \le 1$. The behaviour of the equation is "diffusion-like" (respectively, "wave-like") when $0 < \nu \le \frac{1}{2}$…

Analysis of PDEs · Mathematics 2021-10-25 Marianito R. Rodrigo

The study of first passage times for diffusing particles reaching target states is foundational in various practical applications, including diffusion-controlled reactions. In this work, we present a bi-scaling theory for the probability…

Statistical Mechanics · Physics 2025-03-21 Talia Baravi , David A. Kessler , Eli Barkai

We consider an anisotropic needle-like Brownian particle with nematic symmetry confined in a $2D$ domain. For this system, the coupling of translational and rotational diffusion makes the process ${\bf x} (t)$ of the positions of the…

Statistical Mechanics · Physics 2017-02-08 Nicolas Levernier , Olivier Bénichou , Raphaël Voituriez

In this work, we consider an inverse problem of determining a time dependent coefficient in a fully fractional diffusion equation with a nonlinear source term. The nonlocal initial-boundary value problem refers to the forward model: the…

Analysis of PDEs · Mathematics 2025-12-10 D. K. Durdiev , H. H. Turdiev

We investigate a class of diffusion-controlled reactions that are initiated at the time instance when a prescribed number $K$ among $N$ particles independently diffusing in a solvent are simultaneously bound to a target region. In the…

Chemical Physics · Physics 2023-10-17 Denis S. Grebenkov , Aanjaneya Kumar

Quantifying how spatial disorder affects the movement of a diffusing particle or agent is fundamental to target search studies. When diffusion occurs on a network, that is on a highly disordered environment, we lack the mathematical tools…

Statistical Mechanics · Physics 2025-08-15 Daniel Marris , Chittaranjan Hens , Subrata Ghosh , Luca Giuggioli

In this paper, we present an inverse problem of identifying the reaction coefficient for time fractional diffusion equations in two dimensional spaces by using boundary Neumann data. It is proved that the forward operator is continuous with…

Numerical Analysis · Mathematics 2018-06-14 Xiaoyan Song , Guanghui Zheng , Lijian Jiang