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Related papers: Diffusion in an expanding medium: Fokker-Planck eq…

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We study the main properties of the solution of a Fokker-Planck equation characterized by a variable diffusion coefficient and a polynomial superlinear drift, modeling the formation of consensus in a large interacting system of individuals.…

Analysis of PDEs · Mathematics 2025-04-18 Giuseppe Toscani , Mattia Zanella

In these lecture notes, we explore the mathematical preliminaries and foundational concepts that connect stochastic processes with partial differential equations. We begin by investigating Brownian motion, which serves as a model for random…

Probability · Mathematics 2025-09-15 Helder Rojas

We consider single particle and polymer translocation where the frictional properties experienced from the environment are changing in time. This work is motivated by the interesting frequency responsive behaviour observed when a polymer is…

Soft Condensed Matter · Physics 2012-12-06 Jack A. Cohen , Abhishek Chaudhuri , Ramin Golestanian

By making use of the Green function concept of quantization of the electromagnetic field in Kramers--Kronig consistent media, a rigorous quantum mechanical derivation of the rate of intermolecular energy transfer in the presence of…

Quantum Physics · Physics 2016-08-16 Ho Trung Dung , Ludwig Knöll , Dirk-Gunnar Welsch

We study scalar perturbations to a Robertson-Walker cosmological metric in terms of a pseudo-Newtonian potential, which emerges naturally from the solution of the field equations. This potential is given in terms of a Green function for…

Astrophysics · Physics 2009-10-22 Mark W Jacobs , Eric V Linder , Robert V Wagoner

We give an example of a mathematical model describing quantum mechanical processes interacting with medium. As a model, we consider the process of heat scattering of a wave function defined on the phase space. We consider the case when the…

Mathematical Physics · Physics 2016-03-22 E. M. Beniaminov

Propagation of traveling fronts in three-dimensional reaction-diffusion media with spatially modulated cross-section is studied using the Schl\"ogl model as a representative example. Applying appropriate perturbation techniques leads first…

Pattern Formation and Solitons · Physics 2015-02-26 S. Martens , J. Löber , H. Engel

Very recent experiments have discovered that localized light in strongly absorbing media displays intriguing diffusive phenomena. Here we develop a first-principles theory of light propagation in open media with arbitrary absorption…

Optics · Physics 2013-10-30 Li-Yi Zhao , Chu-Shun Tian , Zhao-Qing Zhang , Xiang-Dong Zhang

Evaluating the completion time of a random algorithm or a running stochastic process is a valuable tip not only from a purely theoretical, but also pragmatic point of view. In the formal sense, this kind of a task is specified in terms of…

Statistical Mechanics · Physics 2022-11-24 Przemyslaw Chelminiak

We derive the hydrodynamic limit of a kinetic equation where the interactions in velocity are modelled by a linear operator (Fokker-Planck or Linear Boltzmann) and the force in the Vlasov term is a stochastic process with high amplitude and…

Analysis of PDEs · Mathematics 2020-03-23 Arnaud Debussche , Julien Vovelle

The distribution of the first-passage time (FPT)$T_a$ for a Brownian particle with drift $\mu$ subject to hitting an absorber at a level $a>0$ is well-known and given by its density $\gamma(t) = \frac{a}{\sqrt{2 \pi t^3} } e^{-\frac{(a-\mu…

Statistical Mechanics · Physics 2024-09-04 Alain Mazzolo

We investigate the extreme value statistics of a one-dimensional Brownian motion (with the diffusion constant $D$) during a time interval $\left[0, t \right]$ in the presence of a reflective boundary at the origin, starting from a positive…

Statistical Mechanics · Physics 2024-01-26 Feng Huang , Hanshuang Chen

We consider the fractional generalizations of equation that defines the medium mass. We prove that the fractional integrals can be used to describe the media with noninteger mass dimensions. Using fractional integrals, we derive the…

Chaotic Dynamics · Physics 2015-06-26 Vasily E. Tarasov

In this work we establish a link between two different phenomena that were studied in a large and growing number of biological, composite and soft media: the diffusion in compartmentalized environment and the Brownian yet non-Gaussian…

Statistical Mechanics · Physics 2020-08-05 Jakub Ślęzak , Stanislav Burov

Functionals of Brownian motion have diverse applications in physics, mathematics, and other fields. The probability density function (PDF) of Brownian functionals satisfies the Feynman-Kac formula, which is a Schrodinger equation in…

Statistical Mechanics · Physics 2010-11-25 Shai Carmi , Lior Turgeman , Eli Barkai

A Langevin equation is suggested to describe a system driven by correlated Gaussian white noise as well as with positive and negative damping demarcated by a critical velocity. The equation can be transformed into the Fokker-Planck equation…

Physics and Society · Physics 2019-09-11 Peng Wang , Feng-Chun Pan , Jie Huo , Xu-Ming Wang

We consider the general problem of the first passage distribution of particles whose displacements are subject to time delays. We show that this problem gives rise to a \emph{propagation-dispersion equation} which is obtained as the…

Statistical Mechanics · Physics 2009-11-10 Jean Pierre Boon , Patrick Grosfils , James F. Lutsko

We prove that for a standard Brownian motion, there exists a first-passage-time density function through a locally H\"older continuous curve with exponent greater than 1/2. By using a property of local time of a standard Brownian motion and…

Analysis of PDEs · Mathematics 2018-08-08 Jimyeong Lee

In inhomogeneous environments, the correct expression of the diffusive flux is often not given by the Fick's law $\Gamma = - D \nabla n $. The most general hydrodynamic equation modelling diffusion is indeed the Fokker-Planck Equation…

Plasma Physics · Physics 2009-03-18 F. Sattin

The Fokker-Planck equation provides complete statistical description of a particle undergoing random motion in a solvent. In the presence of Lorentz force due to an external magnetic field, the Fokker-Planck equation picks up a tensorial…

Statistical Mechanics · Physics 2020-01-22 Iman Abdoli , Hidde Derk Vuijk , Jens-Uwe Sommer , Joseph Michael Brader , Abhinav Sharma