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We examine the relation between inter-particle interactions and real-time equilibration in one-dimensional lattice systems with hard-core constraints. Focusing on the roles of interactions, our results demonstrate that in the presence of…

Quantum Gases · Physics 2025-03-04 Wei-Han Li

We investigate chaos in mixed-phase-space Hamiltonian systems using time series of the finite- time Lyapunov exponents. The methodology we propose uses the number of Lyapunov exponents close to zero to define regimes of ordered…

Chaotic Dynamics · Physics 2015-06-16 R. M. da Silva , C. Manchein , M. W. Beims , E. G. Altmann

Motivated by recent experiments, we model the dynamics of bright solitons formed by cold gases in quasi-1D traps. A dynamical variational ansatz captures the far-from equilibrium excitations of these solitons. Due to a separation of scales,…

Quantum Gases · Physics 2019-06-05 Daniel Longenecker , Erich J. Mueller

A new method is proposed for integrating the equations of motion of an elastic filament. In the standard finite-difference and finite-element formulations the continuum equations of motion are discretized in space and time, but it is then…

Computational Physics · Physics 2009-11-13 Anthony JC Ladd , Gaurav Misra

When numerically integrating canonical Hamiltonian systems, the long-term conservation of some of its invariants, among which the Hamiltonian function itself, assumes a central role. The classical approach to this problem has led to the…

Numerical Analysis · Mathematics 2012-06-21 Luigi Brugnano , Felice Iavernaro , Donato Trigiante

To a very good approximation, particularly for hadron machines, charged-particle trajectories in accelerators obey Hamiltonian mechanics. During routine storage times of eight hours or more, such particles execute some $10^{8}$ revolutions…

Accelerator Physics · Physics 2022-11-02 Dan T. Abell , Alex J. Dragt

The aim of this paper is to introduce a class of Hamiltonian autonomous systems in dimension 4 which are completely integrable and their dynamics is described in all details. They have an equilibrium point which is stable for some rare…

Dynamical Systems · Mathematics 2014-02-04 Gaetano Zampieri

Simulation of many-particle system evolution by molecular dynamics takes to decrease integration step to provide numerical scheme stability on the sufficiently large time interval. It leads to a significant increase of the volume of…

Numerical Analysis · Mathematics 2016-05-19 Eduard G. Nikonov

A new Monte-Carlo method for long-range interacting systems is presented. This method consists of eliminating interactions stochastically with the detailed balance condition satisfied. When a pairwise interaction $V_{ij}$ of a $N$-particle…

Disordered Systems and Neural Networks · Physics 2015-05-13 Munetaka Sasaki , Fumitaka Matsubara

We present the results of simulation of the chaotic dynamics of quantized vortices in the bulk of superfluid He II. Evolution of vortex lines is calculated on the base of the Biot-Savart law. The dissipative effects appeared from the…

Condensed Matter · Physics 2016-08-31 L. P. Kondaurova , S. K. Nemirovskii , M. V. Nedoboiko

Taking advantage of the flexibility of the variational method with coordinate transformations, we derive a self-consistent set of equations of motion from a discretized Lagrangian to study kinetic plasmas using a Fourier decomposed…

Computational Physics · Physics 2014-11-04 A. B. Stamm , B. A. Shadwick

Temporal evolutions toward thermal equilibria are numerically investigated in a Hamiltonian system with many degrees of freedom which has second order phase transition. Relaxation processes are studied through local order parameter, and…

chao-dyn · Physics 2009-10-28 Yoshiyuki Y. Yamaguchi

Stochastic contact Hamiltonian systems are a class of important mathematical models, which can describe the dissipative properties with odd dimensions in the stochastic environment. In this article, we investigate the numerical dynamics of…

Numerical Analysis · Mathematics 2024-11-19 Qingyi Zhan , Jinqiao Duan , Xiaofan Li , Lijin Wang

Long ranged electrostatic interactions are time consuming to calculate in molecular dynamics and Monte-Carlo simulations. We introduce an algorithmic framework for simulating charged particles which modifies the dynamics so as to allow…

Statistical Mechanics · Physics 2009-09-07 A. C. Maggs , V. Rossetto

For the calculation of the partition function $\mathcal{Z}$ of small, isolated and interacting many body systems an improvement with respect to previous formulations is presented. By including anharmonicities and employing a variational…

Nuclear Theory · Physics 2009-11-10 Christian Rummel , Helmut Hofmann

We develop physically admissible lattice models in the harmonic approximation which define by Hamilton's variational principle fractional Laplacian matrices of the forms of power law matrix functions on the n -dimensional periodic and…

Mathematical Physics · Physics 2016-10-13 T. M. Michelitsch , B. A. Collet , A. P. Riascos , A. F. Nowakowski , F. C. G. A. Nicolleau

We present a technique for optimizing hundreds of thousands of variational parameters in variational quantum Monte Carlo. By introducing iterative Krylov subspace solvers and by multiplying by the Hamiltonian and overlap matrices as they…

Strongly Correlated Electrons · Physics 2013-05-30 Eric Neuscamman , C. J. Umrigar , Garnet Kin-Lic Chan

Lattice gas automata with collision rules that violate the conditions of semi-detailed-balance exhibit algebraic decay of equal time spatial correlations between fluctuations of conserved densities. This is shown on the basis of a…

Condensed Matter · Physics 2009-10-28 H. J. Bussemaker , M. H. Ernst

Recently, there has been an increasing interest in modelling and computation of physical systems with neural networks. Hamiltonian systems are an elegant and compact formalism in classical mechanics, where the dynamics is fully determined…

Numerical Analysis · Mathematics 2022-06-28 Elena Celledoni , Andrea Leone , Davide Murari , Brynjulf Owren

In ergodic quantum systems, physical observables have a non-relaxing component if they "overlap" with a conserved quantity. In interacting microscopic models, how to isolate the non-relaxing component is unclear. We compute exact dynamical…

Statistical Mechanics · Physics 2019-11-13 Matteo Bellitti , Siddhardh Morampudi , Chris R. Laumann
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