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We propose a hierarchical splitting approach to differential equations that provides a design principle for constructing splitting methods for $N$-split systems by iteratively applying splitting methods for two-split systems. We analyze the…

Numerical Analysis · Mathematics 2026-01-21 Kevin Schäfers , Michael Günther

A fixed time-step variational integrator cannot preserve momentum, energy, and symplectic form simultaneously for nonintegrable systems. This barrier can be overcome by treating time as a discrete dynamic variable and deriving adaptive…

Numerical Analysis · Mathematics 2022-08-17 Harsh Sharma , Jeff Borggaard , Mayuresh Patil , Craig Woolsey

We present a new time integrator for articulated body dynamics. We formulate the governing equations of the dynamics using only the position variables and recast the position-based articulated dynamics as an optimization problem. Our…

Robotics · Computer Science 2018-07-24 Zherong Pan , Dinesh Manocha

Splitting schemes are numerical integrators for Hamiltonian problems that may advantageously replace the St\"ormer-Verlet method within Hamiltonian Monte Carlo (HMC) methodology. However, HMC performance is very sensitive to the step size…

Numerical Analysis · Mathematics 2022-12-02 F. Diele , C. Marangi , C. Tamborrino , C. Tarantino

We present a family of multistep integrators based on the Adams-Bashforth methods. These schemes can be constructed for arbitrary convergence order with arbitrary step size variation. The step size can differ between different subdomains of…

Numerical Analysis · Mathematics 2020-06-19 William Throwe , Saul A. Teukolsky

This paper formulates variational integrators for finite element discretizations of deformable bodies with heat conduction in the form of finite speed thermal waves. The cornerstone of the construction consists in taking advantage of the…

Mathematical Physics · Physics 2014-03-18 Pablo Mata A , Adrian J Lew

We present a new implicit asymptotic preserving time integration scheme for charged-particle orbit computation in arbitrary electromagnetic fields. The scheme is built on the Crank-Nicolson integrator and continues to recover full-orbit…

Computational Physics · Physics 2020-07-15 Lee F. Ricketson , Luis Chacón

When fitting N-body models to astronomical data - including transit times, radial velocity, and astrometric positions at observed times - the derivatives of the model outputs with respect to the initial conditions can help with model…

Earth and Planetary Astrophysics · Physics 2021-09-01 Eric Agol , David M. Hernandez , Zachary Langford

Symplectic integrators are a foundation to the study of dynamical $N$-body phenomena, at scales ranging from from planetary to cosmological. These integrators preserve the Poincar\'e invariants of Hamiltonian dynamics. The $N$-body…

Earth and Planetary Astrophysics · Physics 2019-10-09 David M. Hernandez

We present a class of non-standard numerical schemes which are modifications of the discrete gradient method. They preserve the energy integral exactly (up to the round-off error). The considered class contains locally exact discrete…

Numerical Analysis · Computer Science 2013-08-08 Jan L. Cieśliński , Bogusław Ratkiewicz

Geometric integrators of the Schr\"{o}dinger equation conserve exactly many invariants of the exact solution. Among these integrators, the split-operator algorithm is explicit and easy to implement, but, unfortunately, is restricted to…

Chemical Physics · Physics 2024-09-26 Seonghoon Choi , Jiří Vaníček

The time-symmetric block time--step (TSBTS) algorithm is a newly developed efficient scheme for $N$--body integrations. It is constructed on an era-based iteration. In this work, we re-designed the TSBTS integration scheme with dynamically…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 M. Kaplan , H. Saygin

We present a new symplectic integrator designed for collisional gravitational $N$-body problems which makes use of Kepler solvers. The integrator is also reversible and conserves 9 integrals of motion of the $N$-body problem to machine…

Instrumentation and Methods for Astrophysics · Physics 2017-03-03 David M. Hernandez , Edmund Bertschinger

A new approach for integration of motion in many-body systems of interacting polyatomic molecules is proposed. It is based on splitting time propagation of pseudo-variables in a modified phase space, while the real translational and…

Statistical Mechanics · Physics 2009-11-13 Igor P. Omelyan

In this paper we propose and investigate a general approach to constructing local energy-preserving algorithms which can be of arbitrarily high order in time for solving Hamiltonian PDEs. This approach is based on the temporal…

Numerical Analysis · Mathematics 2021-03-31 Yuwen Li , Xinyuan Wu

Symplectic N-body integrators are widely used to study problems in celestial mechanics. The most popular algorithms are of 2nd and 4th order, requiring 2 and 6 substeps per timestep, respectively. The number of substeps increases rapidly…

Astrophysics · Physics 2009-10-31 J. E. Chambers , M. A. Murison

In this paper, an implicit nonsymplectic exact energy-preserving integrator is specifically designed for a ten-dimensional phase-space conservative Hamiltonian system with five degrees of freedom. It is based on a suitable…

General Relativity and Quantum Cosmology · Physics 2021-04-16 Shiyang Hu , Xin Wu , Enwei Liang

We present two types of meta-algorithm that can greatly improve the accuracy of existing algorithms for integrating the equations of motion of dynamical systems. The first meta-algorithm takes an integrator that is time-symmetric only for…

Astrophysics · Physics 2007-05-23 Piet Hut , Yoko Funato , Eiichiro Kokubo , Junichiro Makino , Steve McMillan

In this paper structure-preserving time-integrators for rigid body-type mechanical systems are derived from a discrete Hamilton-Pontryagin variational principle. From this principle one can derive a novel class of variational partitioned…

Numerical Analysis · Mathematics 2008-01-08 Nawaf Bou-Rabee , Jerrold E. Marsden

We design a novel, exactly energy-conserving implicit non-symplectic integration method for an eight-dimensional Hamiltonian system with four degrees of freedom. In our algorithm, each partial derivative of the Hamiltonian with respect to…

General Relativity and Quantum Cosmology · Physics 2019-12-30 Shiyang Hu , Xin Wu , Guoqing Huang , Enwei Liang