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Related papers: Simplified P$_N$ Equations for Nonclassical Transp…

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We demonstrate the scattering anisotropy treatment of the previously developed analytical solution for 1D multigroup $S_N$ equations.

Computational Physics · Physics 2024-07-03 Jilang Miao , Miaomiao Jin

In this note, we are concerned with the asymptotic approximation of a class of double integrals which can be represented as an angular spectrum superposition. These double integrals typically appear in electromagnetic scattering problems.…

Mathematical Physics · Physics 2007-05-23 Fei Wang

We introduce and study a notion of Asymptotic Preserving schemes, related to convergence in distribution, for a class of slow-fast Stochastic Differential Equations. In some examples, crude schemes fail to capture the correct limiting…

Numerical Analysis · Mathematics 2020-11-05 Charles-Edouard Bréhier , Shmuel Rakotonirina-Ricquebourg

We show that, by correctly selecting the probability distribution function $p(s)$ for a particle's distance-to-collision, the nonclassical diffusion equation can be represented exactly by the nonclassical linear Boltzmann equation for an…

Mathematical Physics · Physics 2016-02-03 Richard Vasques

Electronic transport through chaotic quantum dots exhibits universal behaviour which can be understood through the semiclassical approximation. Within the approximation, transport moments reduce to codifying classical correlations between…

Mathematical Physics · Physics 2016-03-25 G. Berkolaiko , J. Kuipers

We propose a simple, intuitive alternative method of deriving the rule for connecting asymptotic wave function amplitudes to scattering probabilities. This is illustrated using the standard example of a 1-D particle reflecting or…

Quantum Physics · Physics 2009-10-09 Travis Norsen

Periodic orbit quantization requires an analytic continuation of non-convergent semiclassical trace formulae. We propose a method for semiclassical quantization based upon the Pade approximant to the periodic orbit sums. The Pade…

chao-dyn · Physics 2009-10-31 J. Main , P. A. Dando , Dz. Belkic , H. S. Taylor

An asymptotic expansion with respect to a small parameter of the solution of the Cauchy problem is constructed for a system of three transfer equations, two of which are singularly perturbed by the degeneracy of the entire senior part of…

Analysis of PDEs · Mathematics 2023-08-22 Andrey Nesterov

An asymptotic limit of a class of Cahn-Hilliard systems is investigated to obtain a general nonlinear diffusion equation. The target diffusion equation may reproduce a number of well-known model equations: Stefan problem, porous media…

Analysis of PDEs · Mathematics 2015-12-01 Pierluigi Colli , Takeshi Fukao

In this paper, we develop a new strategy aimed at obtaining high-order asymptotic models for transport equations with highly-oscillatory solutions. The technique relies upon recent developments averaging theory for ordinary differential…

Numerical Analysis · Mathematics 2016-11-15 Philippe Chartier , Nicolas Crouseilles , Mohammed Lemou

We investigate electron transport through clean open quantum dots (quantum billiards). We present a semiclassical theory that allows to accurately reproduce quantum transport calculations. Quantitative agreement is reached for individual…

Mesoscale and Nanoscale Physics · Physics 2010-04-30 Iva Brezinova , Ludger Wirtz , Stefan Rotter , Christoph Stampfer , Joachim Burgdorfer

We consider the motion of a particle on a surface which is a small perturbation of the standard sphere. One may qualitatively describe the motion by means of a precessing great circle of the sphere. The observation is employed to derive a…

Mathematical Physics · Physics 2007-05-23 V. L. Golo , D. O. Sinitsyn

The chaotic scattering theory is here extended to obtain escape-rate expressions for the transport coefficients appropriate for a simple classical fluid, or for a chemically reacting system. This theory allows various transport coefficients…

chao-dyn · Physics 2009-10-22 J. R. Dorfman , P. Gaspard

We provide an asymptotic analysis of linear transport problems in the diffusion limit under minimal regularity assumptions on the domain, the coefficients, and the data. The weak form of the limit equation is derived and the convergence of…

Analysis of PDEs · Mathematics 2014-07-31 Herbert Egger , Matthias Schlottbom

We analyze the well-posedness of an anisotropic, nonlocal diffusion equation. Establishing an equivalence between weighted and unweighted anisotropic nonlocal diffusion operators in the vein of unified nonlocal vector calculus, we apply our…

Analysis of PDEs · Mathematics 2021-01-13 Marta D'Elia , Mamikon Gulian

Rendering highly scattering participating media using brute force path tracing is a challenge. The diffusion approximation reduces the problem to solving a simple linear partial differential equation. Flux-limited diffusion introduces…

Graphics · Computer Science 2018-07-03 David Koerner , Jamie Portsmouth , Wenzel Jakob

In this paper, we investigate the asymptotic error distributions of symplectic methods for stochastic Hamiltonian systems and further provide Hamiltonian-specific analysis that clarifies the superiority of symplectic methods. Our…

Numerical Analysis · Mathematics 2025-12-04 Chuchu Chen , Xinyu Chen , Jialin Hong , Yuqian Miao

This article introduces a new class of fast algorithms to approximate variational problems involving unbalanced optimal transport. While classical optimal transport considers only normalized probability distributions, it is important for…

Optimization and Control · Mathematics 2017-05-23 Lenaic Chizat , Gabriel Peyré , Bernhard Schmitzer , François-Xavier Vialard

We consider a class of dissipative stochastic differential equations (SDE's) with time-periodic coefficients in finite dimension, and the response of time-asymptotic probability measures induced by such SDE's to sufficiently regular, small…

Probability · Mathematics 2022-01-04 Michal Branicki , Kenneth Uda

In the article, new asymptotic approximation of the $n$th order is obtained and proposed to be used in calculations of radiation propagation without scattering in optically thick media; the asymptotic approximation is much simpler and more…

Instrumentation and Methods for Astrophysics · Physics 2020-12-23 S. A. Serov , S. S. Serova