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Related papers: X-ray Fokker--Planck equation for paraxial imaging

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A Lagrangian numerical scheme for solving nonlinear degenerate Fokker-Planck equations in space dimensions $d\ge2$ is presented. It applies to a large class of nonlinear diffusion equations, whose dynamics are driven by internal energies…

Numerical Analysis · Mathematics 2018-06-18 José A. Carrillo , Bertram Düring , Daniel Matthes , David S. McCormick

In neuroscience, the distribution of a decision time is modelled by means of a one-dimensional Fokker--Planck equation with time-dependent boundaries and space-time-dependent drift. Efficient approximation of the solution to this equation…

Numerical Analysis · Mathematics 2023-02-08 Udo Boehm , Sonja Cox , Gregor Gantner , Rob Stevenson

We develop a recursive method for perturbative solutions of the Fokker-Planck equation with nonlinear drift. The series expansion of the time-dependent probability density in terms of powers of the coupling constant is obtained by solving a…

Statistical Mechanics · Physics 2009-12-06 Jens Dreger , Axel Pelster , Bodo Hamprecht

A pointlike particle of finite mass m, moving in a one-dimensional viscous environment and biased by a spatially dependent force, is considered. We present a rigorous mapping of the Fokker-Planck equation, which determines evolution of the…

Statistical Mechanics · Physics 2012-09-24 Pavol Kalinay , Jerome K. Percus

The goal of this investigation was to derive strictly new properties of chaotic systems and their mutual relations. The generalized Fokker-Planck equation with a non stationary diffusion has been derived and used for chaos analysis. An…

Chaotic Dynamics · Physics 2014-07-29 Sergey A. Kamenshchikov

Using the method of Laplace transform the field amplitude in the paraxial approximation is found in the two-dimensional free space using initial values of the amplitude specified on an arbitrary shaped monotonic curve. The obtained…

Computational Physics · Physics 2018-04-12 R M Feshchenko , A V Vinogradov , I A Artyukov

We present a new path integral method to analyze stochastically perturbed ordinary differential equations with multiple time scales. The objective of this method is to derive from the original system a new stochastic differential equation…

Pattern Formation and Solitons · Physics 2007-08-20 Tobias Schaefer Richard O. Moore

The problem of optimization of propagation-based phase-contrast imaging setups is considered in the case of projection X-ray imaging and three-dimensional tomography with phase retrieval. For two-dimensional imaging, a simple model for a…

Medical Physics · Physics 2026-03-03 T. E. Gureyev , D. M. Paganin , H. M. Quiney

In a previous work, a perturbative approach to a class of Fokker-Planck equations, which have constant diffusion coefficients and small time-dependent drift coefficients, was developed by exploiting the close connection between the…

Mathematical Physics · Physics 2015-05-27 Wen-Tsan Lin , Choon-Lin Ho

This paper deals with uncertainty propagation of general stochastic hybrid systems (GSHS) where the continuous state space is a compact Lie group. A computational framework is proposed to solve the Fokker-Planck (FP) equation that describes…

Optimization and Control · Mathematics 2022-03-08 Weixin Wang , Taeyoung Lee

Particle acceleration by turbulence plays a role in many astrophysical environments. The non- linear evolution of the underlying cosmic-ray spectrum is complex and can be described by a Fokker-Planck equation, which in general has to be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Julius Donnert , Gianfranco Brunetti

The Fokker-Planck equation has been very useful for studying dynamic behavior of stochastic differential equations driven by Gaussian noises. In this paper, we derive a Fractional Fokker--Planck equation for the probability distribution of…

Analysis of PDEs · Mathematics 2009-11-10 D. Schertzer , M. Larchev , J. Duan , V. V. Yanovsky , S. Lovejoy

We analyse a generalised Fokker-Planck equation by making essential use of its linearisability through a Cole-Hopf transformation. We determine solutions of travelling wave and multi-kink type by resorting to a geometric construction in the…

Mathematical Physics · Physics 2025-04-29 Francesco Giglio , Giulio Landolfi , Luigi Martina , Andrea Zingarofalo

Transport events in turbulent tokamak plasmas often exhibit non-local or non-diffusive action at a distance features that so far have eluded a conclusive theoretical description. In this paper a theory of non-local transport is investigated…

Plasma Physics · Physics 2015-05-27 S. Moradi , J. Anderson , B. Weyssow

A cross-diffusion system for two compoments with a Laplacian structure is analyzed on the multi-dimensional torus. This system, which was recently suggested by P.-L. Lions, is formally derived from a Fokker-Planck equation for the…

Analysis of PDEs · Mathematics 2017-03-08 Ansgar Jüngel , Nicola Zamponi

This paper addresses uncertainty propagation on unimodular matrix Lie groups that have a surjective exponential map. We derive the exact formula for the propagation of mean and covariance in a continuous-time setting from the governing…

Systems and Control · Electrical Eng. & Systems 2023-12-07 Jikai Ye , Amitesh S. Jayaraman , Gregory S. Chirikjian

Solving the stationary nonlinear Fokker-Planck equations is important in applications and examples include the Poisson-Boltzmann equation and the two layer neural networks. Making use of the connection between the interacting particle…

Numerical Analysis · Mathematics 2023-10-03 Lei Li , Yijia Tang , Jingtong Zhang

By constructing successful couplings for degenerate diffusion processes, explicit derivative formula and Harnack type inequalities are presented for solutions to a class of degenerate Fokker-Planck equations on $\R^m\times\R^{d}$. The main…

Probability · Mathematics 2012-03-13 Arnaud Guillin , Feng-Yu Wang

The method of choice for integrating the time-dependent Fokker-Planck equation in high-dimension is to generate samples from the solution via integration of the associated stochastic differential equation. Here, we study an alternative…

Machine Learning · Computer Science 2023-02-17 Nicholas M. Boffi , Eric Vanden-Eijnden

The interaction of charged particles, moving in a uniform magnetic field, with a plane-polarized gravitational wave is considered using the Fokker-Planck- Kolmogorov (FPK) approach. By using a stochasticity criterion, we determine the exact…

General Relativity and Quantum Cosmology · Physics 2015-06-25 A. Anastasiadis , K. Kleidis , H. Varvoglis
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