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Related papers: Variational Methods for Path Integral Scattering

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We investigate variational methods for finding approximate solutions to the Fokker-Planck equation, especially in cases lacking detailed balance. These schemes fall into two classes: those in which a Hermitian operator is constructed from…

Condensed Matter · Physics 2009-10-28 T. Blum , A. J. McKane

We study an approximation scheme based on a second quantization method for a chemical master equation. Small systems, such as cells, could not be studied by the traditional rate equation approach because fluctuation effects are very large…

Chemical Physics · Physics 2010-06-18 Jun Ohkubo

Sharp-momentum transition matrix elements for scattering from a short-range Gaussian potential are computed using a real-time path integral. The computation is based on a numerical implementation of a new interpretation of the path integral…

High Energy Physics - Lattice · Physics 2018-09-10 W. N. Polyzou , Ekaterina Nathanson

Discretizations of the Feynman-Kac path integral representation of the quantum mechanical density matrix are investigated. Each infinite-dimensional path integral is approximated by a Riemann integral over a finite-dimensional function…

Statistical Mechanics · Physics 2007-05-23 Stephen D. Bond , Brian B. Laird , Benedict J. Leimkuhler

It is shown that a relativistic multiple scattering theory for hadron-nucleus scattering can be consistently formulated in four-dimensions in the context of meson exchange. We give a multiple scattering series for the optical potential and…

Nuclear Theory · Physics 2008-11-26 Khin Maung Maung , John W. Norbury , Trina Coleman

We report a variational approach to the nonlinearly screened interaction of charged particles with a many-electron system. This approach has been developed by introducing a modification of the Schwinger variational principle of scattering…

Materials Science · Physics 2009-11-11 V. U. Nazarov , S. Nishigaki , J. M. Pitarke , C. S. Kim

We make a relativistic extension of the one-dimensional J-matrix method of scattering. The relativistic potential matrix is a combination of vector, scalar, and pseudo-scalar components. These are non-singular short-range potential…

Quantum Physics · Physics 2020-09-14 A. D. Alhaidari

This article provides a new theory for the analysis of forward and backward particle approximations of Feynman-Kac models. Such formulae are found in a wide variety of applications and their numerical (particle) approximation are required…

Statistics Theory · Mathematics 2014-11-17 Hock Peng Chan , Pierre Del Moral , Ajay Jasra

Asymptotic behavior of the scattering amplitude for two scalar particles by scalar, vector and tensor exchanges at high energy and fixed momentum transfers is reconsidered in quantum field theory. In the framework of the quasi-potential…

High Energy Physics - Theory · Physics 2008-05-02 Nguyen Suan Han , Nguyen Nhu Xuan

Following Feynman's treatment of the non-relativistic polaron problem, similar techniques are used to study relativistic field theories: after integrating out the bosonic degrees of freedom the resulting effective action is formulated in…

High Energy Physics - Theory · Physics 2007-05-23 R. Rosenfelder , C. Alexandrou , A. W. Schreiber

The one-sided bouncer and the symmetric bouncer involve a one-dimensional particle in a piecewise linear potential. For such problems, the time-dependent quantum mechanical propagator cannot be found in closed form. The semiclassical…

Quantum Physics · Physics 2021-09-29 Yen Lee Loh , Chee Kwan Gan

On the basis of the eikonal approximation of quantum scattering theory, the problem of fast charged particles scattering in a thin crystal when particles fall along one its plane of atoms and in a thin layer of amorphous matter is…

Mesoscale and Nanoscale Physics · Physics 2019-08-05 N. F. Shul'ga , V. D. Koriukina

We present a practical $S$-matrix to potential inversion procedure for coupled-channel scattering. The inversion technique developed is applied to non-diagonal $S^J_{ll'}$ for spin one projectiles, yielding a tensor interaction $T_{\rm R}$,…

Nuclear Theory · Physics 2009-10-31 S. G. Cooper , V. I. Kukulin , R. S. Mackintosh , V. N. Pomerantsev

The transition-matrix ($T$-matrix) approach provides a general formalism to study scattering problems in various areas of physics, including acoustics (scalar fields) and electromagnetics (vector fields), and is related to the theory of the…

Optics · Physics 2016-02-08 Eric C. Le Ru , Walter R. C. Somerville , Baptiste Auguié

This paper introduces a framework for simulating finite dimensional representations of (jump) diffusion sample paths over finite intervals, without discretisation error (exactly), in such a way that the sample path can be restored at any…

Methodology · Statistics 2016-02-10 Murray Pollock , Adam M. Johansen , Gareth O. Roberts

We investigate, by numerical simulation, the path probability of non dissipative mechanical systems undergoing stochastic motion. The aim is to search for the relationship between this probability and the usual mechanical action. The model…

Statistical Mechanics · Physics 2015-06-17 T. L. Lin , R. Wang , W. P. Bi , A. El Kaabouchi , C. Pujos , F. Calvayrac , Q. A. Wang

Many integral equation-based methods are available for problems of time-harmonic electromagnetic scattering from perfect electric conductors. Among the many challenges that arise in such calculations are the avoidance of spurious…

Numerical Analysis · Mathematics 2025-07-17 Felipe Vico , Leslie Greengard , Michael O'Neil , Manas Rachh

Study of scattering process in the nonlocal interaction framework leads to an integro-differential equation. The purpose of the present work is to develop an efficient approach to solve this integro-differential equation with high degree of…

Nuclear Theory · Physics 2018-08-09 N. J. Upadhyay , A. Bhagwat

We introduce a nonperturbative approximation scheme for performing scattering calculations in two dimensions that involves neglecting the contribution of the evanescent waves to the scattering amplitude. This corresponds to replacing the…

Quantum Physics · Physics 2023-07-21 Farhang Loran , Ali Mostafazadeh

For distinguishable particles it is well known that Brownian motion and a Feynman-Kac functional can be used to calculate the path integral (for imaginary times) for a general class of scalar potentials. In order to treat identical…

Condensed Matter · Physics 2009-10-28 L. F. Lemmens , F. Brosens , J. T. Devreese