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Related papers: Variational calculus for diffusions

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We investigate anomalous diffusion processes governed by the fractional Langevin equation and confined to a finite or semi-infinite interval by reflecting potential barriers. As the random and damping forces in the fractional Langevin…

Statistical Mechanics · Physics 2019-11-01 Thomas Vojta , Sarah Skinner , Ralf Metzler

The paper is devoted to the properties of the entropy of the exponent-Wiener-integral fractional Gaussian process (EWIFG-process), that is a Wiener integral of the exponent with respect to fractional Brownian motion. Unlike fractional…

Probability · Mathematics 2025-02-03 Iryna Bodnarchuk , Yuliya Mishura , Kostiantyn Ralchenko

We apply Frobenius integrability theorem in the search of invariants for one-dimensional Hamiltonian systems with a time-dependent potential. We obtain several classes of potential functions for which Frobenius theorem assures the existence…

Mathematical Physics · Physics 2009-11-07 F. Haas

This paper is concerned with the fractionalized diffusion equations governing the law of the fractional Brownian motion $B_H(t)$. We obtain solutions of these equations which are probability laws extending that of $B_H(t)$. Our analysis is…

Probability · Mathematics 2015-09-28 Roberto Garra , Enzo Orsingher , Federico Polito

We develop a general framework for finding error estimates for convection-diffusion equations with nonlocal, nonlinear, and possibly degenerate diffusion terms. The equations are nonlocal because they involve fractional diffusion operators…

Analysis of PDEs · Mathematics 2013-10-08 Nathaël Alibaud , Simone Cifani , Espen R. Jakobsen

The random motion of a Brownian particle confined in some finite domain is considered. Quite generally, the relevant statistical properties involve infinite series, whose coefficients are related to the eigenvalues of the diffusion…

Statistical Mechanics · Physics 2010-04-26 Thomas Bickel

In this work, with the help of fractional calculus, it is shown a time dependence of entropy more general than the well known Pesin relation is derived. Here the equiprobability postulate is not assumed, the system dynamic in the phase…

Statistical Mechanics · Physics 2021-05-07 O. Sotolongo-Costa , I. Rodríguez-Vargas

The set of closed (or holonomic) measures provides a useful setting for studying optimization problems because it contains all curves, while also enjoying good compactness and convexity properties. We study the way to do variational…

Optimization and Control · Mathematics 2018-10-19 Rodolfo Rios-Zertuche

Existing deterministic variational inference approaches for diffusion processes use simple proposals and target the marginal density of the posterior. We construct the variational process as a controlled version of the prior process and…

Machine Learning · Computer Science 2021-03-02 Christian Wildner , Heinz Koeppl

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

The solution of a nonlinear diffusion equation is numerically investigated using the generalized Fourier transform method. This equation includes fractal dimensions and power-law dependence on the radial variable and on the diffusion…

Computational Physics · Physics 2019-11-12 Jie Yao , Cameron L. Williams , Fazle Hussain , Donald J. Kouri

The celebrated Sutherland-Einstein relation for systems at thermal equilibrium states that spread of trajectories of Brownian particles is an increasing function of temperature. Here, we scrutinize diffusion of underdamped Brownian motion…

Statistical Mechanics · Physics 2020-04-22 J. Spiechowicz , J. Luczka

We study biased, diffusive transport of Brownian particles through narrow, spatially periodic structures in which the motion is constrained in lateral directions. The problem is analyzed under the perspective of the Fick-Jacobs equation…

Statistical Mechanics · Physics 2007-07-10 P. S. Burada , G. Schmid , D. Reguera , J. M. Rubi , P. Hanggi

Fractional diffusion equations replace the integer-order derivatives in space and time by their fractional-order analogues. They are used in physics to model anomalous diffusion. This paper develops strong solutions of space-time fractional…

Probability · Mathematics 2016-12-19 Zhen-Qing Chen , Mark M. Meerschaert , Erkan Nane

Recently a new type of Kramers-Fokker-Planck Equation has been proposed [R. Friedrich et al. Phys. Rev. Lett. {\bf 96}, 230601 (2006)] describing anomalous diffusion in external potentials. In the present paper the explicit cases of a…

Statistical Mechanics · Physics 2007-05-23 S. Eule , R. Friedrich , F. Jenko

The diffusive motion of overdamped Brownian particles in tilted piecewise linear pontentials is considered. It is shown that the enhancement of diffusion coefficient by an external static force is quite sensitive to the symmetry of periodic…

Soft Condensed Matter · Physics 2007-05-23 Els Heinsalu , Risto Tammelo , Teet Ord

Propagating fronts arising from bistable reaction-diffusion equations are a purely deterministic effect. Stochastic reaction-diffusion processes also show front propagation which coincides with the deterministic effect in the limit of small…

Statistical Mechanics · Physics 2015-05-20 E. Khain , Y. T. Lin , L. M. Sander

The exponent of anomalous diffusion of virus in cytoplasm of a living cell is experimentally known to fluctuate depending on localized areas of the cytoplasm, indicating heterogeneity of diffusion. In a recent paper (Itto, 2012), a…

Biological Physics · Physics 2016-07-14 Yuichi Itto

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 inverse problem of determining different type of information about a diffusion process, described by ordinary or fractional diffusion equations stated on a bounded domain, like the density of the medium or the velocity field…

Analysis of PDEs · Mathematics 2019-07-05 Yavar Kian , Zhiyuan Li , Yikan Liu , Masahiro Yamamoto