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In this article, we investigate the relativistic quantum dynamics of spin-$\frac{1}{2}$ particles in (1+2)-dimensional G\"{u}rses space-time backgrounds, and analyze the effects on the eigenvalues. We solve the Dirac equation using the…

General Relativity and Quantum Cosmology · Physics 2019-11-05 Faizuddin Ahmed

The increased demand for online prediction and the growing availability of large data sets drives the need for computationally efficient models. While exact Gaussian process regression shows various favorable theoretical properties…

Machine Learning · Computer Science 2021-08-02 Armin Lederer , Alejandro Jose Ordonez Conejo , Korbinian Maier , Wenxin Xiao , Jonas Umlauft , Sandra Hirche

We present four frequently used finite difference methods and establish the error bounds for the discretization of the Dirac equation in the massless and nonrelativistic regime, involving a small dimensionless parameter $0< \varepsilon \ll…

Numerical Analysis · Mathematics 2021-05-03 Ying Ma , Jia Yin

A Gaussian quantum theory of bosonic modes has been widely used to describe quantum optical systems, including coherent Ising machines (CIMs) that consist of $\chi^{(2)}$ degenerate optical parametric oscillators (DOPOs) as nonlinear…

Quantum Physics · Physics 2024-03-04 Yoshitaka Inui , Edwin Ng , Yoshihisa Yamamoto

We discuss the Dirac equation in a curved 5-dimensional spherically symmetric space-time. The angular part of the solutions is thoroughly studied, in a formulation suited for extending to rotating space-times with equal angular momenta. It…

General Relativity and Quantum Cosmology · Physics 2014-10-29 Y. Brihaye , T. Delsate , N. Sawado , H. Yoshii

Within the past two decades, Gaussian process regression has been increasingly used for modeling dynamical systems due to some beneficial properties such as the bias variance trade-off and the strong connection to Bayesian mathematics. As…

Systems and Control · Electrical Eng. & Systems 2021-02-11 Thomas Beckers

We consider the initial/boundary value problem for a diffusion equation involving multiple time-fractional derivatives on a bounded convex polyhedral domain. We analyze a space semidiscrete scheme based on the standard Galerkin finite…

Numerical Analysis · Mathematics 2015-06-18 Bangti Jin , Raytcho Lazarov , Yikan Liu , Zhi Zhou

A general procedure for construction of the formalism of quantum beam optics for any particle is reviewed. The quantum formalism of spin-1/2 particle beam optics is presented starting {\em ab initio} with the Dirac equation. As an example…

Accelerator Physics · Physics 2017-08-23 Sameen Ahmed Khan

We consider Friedlander's wave equation in two space dimensions in the half-space x > 0 with the boundary condition u(x,y,t)=0 when x=0. For a Gaussian beam w(x,y,t;k) concentrated on a ray path that is tangent to x=0 at (x,y,t)=(0,0,0) we…

Analysis of PDEs · Mathematics 2017-07-13 James Ralston , Neelesh Tiruviluamala

A new method to solve the Dirac equation on a 3D lattice is proposed, in which the variational collapse problem is avoided by the inverse Hamiltonian method and the fermion doubling problem is avoided by performing spatial derivatives in…

Nuclear Theory · Physics 2017-02-14 Z. X. Ren , S. Q. Zhang , J. Meng

We consider the propagation of Gaussian beams in a waveguide with gain and loss in the paraxial approximation governed by the Schr\"odinger equation. We derive equations of motion for the beam in the semiclassical limit that are valid when…

Quantum Physics · Physics 2016-01-29 Eva-Maria Graefe , Alexander Rush , Roman Schubert

In many areas of science and engineering, discovering the governing differential equations from the noisy experimental data is an essential challenge. It is also a critical step in understanding the physical phenomena and prediction of the…

Methodology · Statistics 2026-05-12 Jiuhai Chen , Lulu Kang , Guang Lin

Mean-field SDEs, also known as McKean-Vlasov equations, are stochastic differential equations where the drift and diffusion depend on the current distribution in addition to the current position. We describe an efficient numerical method…

Numerical Analysis · Mathematics 2017-04-25 Peter Kloeden , Tony Shardlow

A basic problem in linear particle optics is to find a symplectic transformation that brings the (symmetric) beam matrix to a special diagonal form, called normal form. The conventional way to do this involves an eigenvalue-decomposition of…

Mathematical Physics · Physics 2015-02-10 Herbert E. Müller

This work is concerned with the accuracy of Gaussian beam superpositions, which are asymptotically valid high frequency solutions to linear hyperbolic partial differential equations and the Schr\"odinger equation. We derive Sobolev and max…

Numerical Analysis · Mathematics 2015-11-02 Hailiang Liu , Olof Runborg , Nicolay M. Tanushev

Numerical simulation of complex optical structures enables their optimization with respect to specific objectives. Often, optimization is done by multiple successive parameter scans, which are time consuming and computationally expensive.…

Computational Physics · Physics 2017-07-27 P. -I. Schneider , X. Garcia Santiago , C. Rockstuhl , S. Burger

The Lewis and Riesenfeld method has been investigated, by Ramos et al in Ref.[1], for quantum systems governed by time-dependent PT symmetric Hamiltonians and particularly where the quantum system is a particle submitted to action of a…

Quantum Physics · Physics 2020-03-18 Walid Koussa , Mustapha Maamache

We investigate the Dirac time-dependent variational method using a Gaussian trial functional for an infinite one dimensional system of Bosons interacting through a repulsive contact interaction. The method produces a set of non-linear time…

Condensed Matter · Physics 2009-10-30 Arthur K. Kerman , Paolo Tommasini

We introduce the concept of numerical Gaussian processes, which we define as Gaussian processes with covariance functions resulting from temporal discretization of time-dependent partial differential equations. Numerical Gaussian processes,…

Machine Learning · Statistics 2017-03-31 Maziar Raissi , Paris Perdikaris , George Em Karniadakis

We investigate the radiation emitted by an ultrarelativistic electron traveling in a 1-dimensional parabolic potential. Having in mind a simplified model for beamstrahlung, we consider the realistic case of the electron motion being highly…

High Energy Physics - Phenomenology · Physics 2018-08-29 Tobias N. Wistisen , Antonino Di Piazza
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