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Related papers: Adaptive Numerical Solution of Kadanoff-Baym Equat…

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In various fields of natural science, the chaotic systems of differential equations are considered more than 50 years. The correct prediction of the behaviour of solutions of dynamical model equations is important in understanding of…

Dynamical Systems · Mathematics 2020-11-24 Alexander N. Pchelintsev

The extraordinary quantum properties of nonequilibrium systems governed by dissipative dynamics have become a focal point in contemporary scientific inquiry. The Nonequilibrium Green's Functions (NEGF) theory provides a versatile method for…

Materials Science · Physics 2024-02-19 Gianluca Stefanucci

The path integral formalism is the building block of many powerful numerical methods for quantum impurity problems. However, existing fermionic path integral based numerical calculations have only been performed in either the imaginary-time…

Strongly Correlated Electrons · Physics 2024-10-10 Ruofan Chen , Chu Guo

In this contribution we develop an efficient reduced order model for solving parametrized linear-quadratic optimal control problems with linear time-varying state system. The fully reduced model combines reduced basis approximations of the…

Numerical Analysis · Mathematics 2024-08-29 Hendrik Kleikamp , Lukas Renelt

An algorithm is proposed for finding numerical solutions of a kinetic equation that describes an infinite system of point articles placed in $\mathbb{R}^d (d \geq 1)$. The particles perform random jumps with pair wise repulsion, in the…

Dynamical Systems · Mathematics 2020-08-03 Igor Omelyan , Yuri Kozitsky , Krzysztof Pilorz

A set of algorithms is presented for efficient numerical calculation of the time evolution of classical dynamical systems. Starting with a first approximation for solving the differential equations that has a "reversible" character, we show…

Classical Physics · Physics 2017-03-22 Charles Schwartz

Computing numerical solutions to fractional differential equations can be computationally intensive due to the effect of non-local derivatives in which all previous time points contribute to the current iteration. In general, numerical…

Numerical Analysis · Mathematics 2016-05-04 Christopher L. MacDonald , Nirupama Bhattacharya , Brian P. Sprouse , Gabriel A. Silva

Active learning parallelization is widely used, but typically relies on fixing the batch size throughout experimentation. This fixed approach is inefficient because of a dynamic trade-off between cost and speed -- larger batches are more…

Machine Learning · Computer Science 2024-10-15 Masaki Adachi , Satoshi Hayakawa , Martin Jørgensen , Xingchen Wan , Vu Nguyen , Harald Oberhauser , Michael A. Osborne

Bayesian estimation approaches, which are capable of combining the information of experimental data from different likelihood functions to achieve high precisions, have been widely used in phase estimation via introducing a controllable…

Quantum Physics · Physics 2021-07-02 Yuxiang Qiu , Min Zhuang , Jiahao Huang , Chaohong Lee

We present a simple and easy to implement method for the numerical solution of a rather general class of Hamilton-Jacobi-Bellman (HJB) equations. In many cases, the considered problems have only a viscosity solution, to which, fortunately,…

Computational Finance · Quantitative Finance 2011-02-17 Jan Hendrik Witte , Christoph Reisinger

In this work, we present a multiple-scale perturbation technique suitable for the study of open quantum systems, which is easy to implement and in few iterative steps allows us to find excellent approximate solutions. For any time-local…

Quantum Physics · Physics 2019-04-30 D. N. Bernal-García , B. A. Rodríguez , H. Vinck-Posada

Considered herein is a modified Newton method for the numerical solution of nonlinear equations where the Jacobian is approximated using a complex-step derivative approximation. We show that this method converges for sufficiently small…

Numerical Analysis · Mathematics 2024-10-03 Dimitrios Mitsotakis

We perform an analysis of a number of approximations and methods used in numerical simulations of real-time Kadanoff-Baym equations based on truncations of the 2PI effective action. We compare the loop expansion to the 1/N expansion and…

High Energy Physics - Phenomenology · Physics 2024-09-11 Anders Tranberg , Gerhard Ungersbäck

This work deals with the problem of choosing a time step for the numerical solution of boundary value problems for parabolic equations. The problem solution is derived using the fully implicit scheme, whereas a time step is selected via…

Numerical Analysis · Computer Science 2013-11-13 Petr N. Vabishchevich

The description of quantum many-body dynamics is extremely challenging on classical computers, as it can involve many degrees of freedom. On the other hand, the time evolution of quantum states is a natural application for quantum computers…

Quantum Physics · Physics 2025-08-20 Ronen Weiss , Alessandro Baroni , Joseph Carlson , Ionel Stetcu

We demonstrate an approach to the numerical solution of nonlinear stochastic differential equations with Markovian switching. Such equations describe the stochastic dynamics of processes where the drift and diffusion coefficients are…

Numerical Analysis · Mathematics 2024-08-28 Cónall Kelly , Kate O'Donovan

Markov chain Monte Carlo algorithms have important applications in counting problems and in machine learning problems, settings that involve estimating quantities that are difficult to compute exactly. How much can quantum computers speed…

Quantum Physics · Physics 2020-02-10 Aram W. Harrow , Annie Y. Wei

We consider a family of variable time-stepping Dahlquist-Liniger-Nevanlinna (DLN) schemes, which is unconditional non-linear stable and second order accurate, for the Allen-Cahn equation. The finite element methods are used for the spatial…

Numerical Analysis · Mathematics 2024-10-01 YiMing Chen , Dianlun Luo , Wenlong Pei , Yulong Xing

The method of choice for integrating the equations of motion of the general N-body problem has been to use an individual time step scheme. For the sake of efficiency, block time steps have been the most popular, where all time step sizes…

Astrophysics · Physics 2009-11-11 Junichiro Makino , Piet Hut , Murat Kaplan , Hasan Saygin

We have presented some practical consequences on the molecular-dynamics simulations arising from the numerical algorithm published recently in paper Int. J. Mod. Phys. C 16, 413 (2005). The algorithm is not a finite-difference method and…

Exactly Solvable and Integrable Systems · Physics 2015-06-26 B. Brzostowski , M. R. Dudek , B. Grabiec , T. Nadzieja