English
Related papers

Related papers: Symplectic integrators with adaptive time steps

200 papers

Accelerated gradient methods have had significant impact in machine learning -- in particular the theoretical side of machine learning -- due to their ability to achieve oracle lower bounds. But their heuristic construction has hindered…

Computation · Statistics 2018-02-16 Michael Betancourt , Michael I. Jordan , Ashia C. Wilson

Symplectic quantization is a functional approach to quantum field theory that allows sampling of quantum fluctuations directly in Minkowski space time by means of a generalized Hamiltonian dynamics in an extra time variable $\tau$ which, at…

High Energy Physics - Lattice · Physics 2026-03-06 Martina Giachello , Francesco Scardino , Giacomo Gradenigo

Relativistic dynamics of a charged particle in time-dependent electromagnetic fields has theoretical significance and a wide range of applications. It is often multi-scale and requires accurate long-term numerical simulations using…

Plasma Physics · Physics 2018-10-24 Ruili Zhang , Yulei Wang , Yang He , Jianyuan Xiao , Jian Liu , Hong Qin , Yifa Tang

Stiff and chaotic differential equations are challenging for time-stepping numerical methods. For explicit methods, the required time step resolution significantly exceeds the resolution associated with the smoothness of the exact solution…

Numerical Analysis · Mathematics 2024-02-28 Jan Scheffel

Modern N-body techniques for planetary dynamics are generally based on symplectic algorithms specially adapted to the Kepler problem. These methods have proven very useful in studying planet formation, but typically require the timestep for…

Astrophysics · Physics 2009-11-13 D. S. McNeil , R. P. Nelson

The choice of numerical integrator in approximating solutions to dynamic partial differential equations depends on the smallest time-scale of the problem at hand. Large-scale deformations in elastic solids contain both shear waves and bulk…

Numerical Analysis · Mathematics 2025-02-21 Edward M. Terrell , Boyce E. Griffith

We show that symplectic Runge-Kutta methods provide effective symplectic integrators for Hamiltonian systems with index one constraints. These include the Hamiltonian description of variational problems subject to position and velocity…

Numerical Analysis · Mathematics 2014-02-28 Robert I McLachlan , Klas Modin , Olivier Verdier , Matt Wilkins

We study the synchronous dynamics of the Hopfield model when a random antisymmetric part is added to the otherwise symmetric synaptic matrix. We use a generating functional technique to derive analytical expressions for the order parameters…

Disordered Systems and Neural Networks · Physics 2007-05-23 Manoranjan P. Singh

In this paper, we combine the method of multiple scales and the method of matched asymptotic expansions to construct uniformly-valid asymptotic solutions to autonomous and non-autonomous difference equations in the neighbourhood of a…

Dynamical Systems · Mathematics 2016-01-14 Cameron L. Hall , Christopher J. Lustri

We investigate the stochastic modified equation which plays an important role in the stochastic backward error analysis for explaining the mathematical mechanism of a numerical method. The contribution of this paper is threefold. First, we…

Numerical Analysis · Mathematics 2019-07-08 Chuchu Chen , Jialin Hong , Chuying Huang

In this report, we propose a new adaptive time filter algorithm for the unsteady Stokes/Darcy model. First we present a first order ${\theta}$-scheme with the variable time step which is one parameter family of Linear Multi-step methods and…

Numerical Analysis · Mathematics 2022-08-29 Yi Qin , Yang Wang , Yi Li , Jian Li

Exponential integrators are time stepping schemes which exactly solve the linear part of a semilinear ODE system. This class of schemes requires the approxima- tion of a matrix exponential in every step, and one successful modern method is…

Numerical Analysis · Mathematics 2016-08-09 Daniel Stone , Gabriel Lord

By exploiting the error functions of explicit symplectic integrators for solving separable Hamiltonians, I show that it is possible to develop explicit, time-reversible symplectic integrators for solving non-separable Hamiltonians of the…

Computational Physics · Physics 2009-09-25 Siu A. Chin

Adaptive time stepping methods for metastable dynamics of the Allen Cahn and Cahn Hilliard equations are investigated in the spatially continuous, semi-discrete setting. We analyse the performance of a number of first and second order…

Numerical Analysis · Mathematics 2020-06-01 Xinyu Cheng , Dong Li , Keith Promislow , Brian Wetton

We construct numerical integrators for Hamiltonian problems that may advantageously replace the standard Verlet time-stepper within Hybrid Monte Carlo and related simulations. Past attempts have often aimed at boosting the order of accuracy…

Numerical Analysis · Mathematics 2015-04-10 Sergio Blanes , Fernando Casas , J. M. Sanz-Serna

We examine the use of synchronization as a mechanism for extracting parameter and state information from experimental systems. We focus on important aspects of this problem that have received little attention previously, and we explore them…

We consider symplectic time integrators in numerical General Relativity and discuss both free and constrained evolution schemes. For free evolution of ADM-like equations we propose the use of the Stoermer-Verlet method, a standard…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ronny Richter , Christian Lubich

In this article, we develop a posteriori error analysis of a nonconforming finite element method for a linear quadratic elliptic distributed optimal control problem with two different set of constraints, namely (i) integral state constraint…

Optimization and Control · Mathematics 2021-08-09 Kamana Porwal , Pratibha Shakya

This paper presents an adaptive symplectic integrator, SQQ-PTQ, developed on the basis of the fixed-step symplectic integrator SQQ. To mitigate the Runge phenomenon, SQQ-PTQ employs Chebyshev interpolation for approximating the action,…

Numerical Analysis · Mathematics 2025-07-22 Keqi Ye , Zizhe Cai , Mingji Wang , Kun Yang , Xiaodong Liu

In this work, we propose a numerical approach for simulations of large deformations of interfaces in a level set framework. To obtain a fast and viable numerical solution in both time and space, temporal discretization is based on the…

General Mathematics · Mathematics 2023-05-30 Aymen Laadhari , Ahmad Deeb