English
Related papers

Related papers: Adaptive stepsize and instabilities in complex Lan…

200 papers

The measured time series from complex systems are renowned for their intricate stochastic behavior, characterized by random fluctuations stemming from external influences and nonlinear interactions. These fluctuations take diverse forms,…

Statistical Mechanics · Physics 2025-03-19 Pyei Phyo Lin , Matthias Wächter , Joachim Peinke , M. Reza Rahimi Tabar

We study numerical methods for sampling probability measures in high dimension where the underlying model is only approximately identified with a gradient system. Extended stochastic dynamical methods are discussed which have application to…

Numerical Analysis · Mathematics 2016-03-08 Benedict Leimkuhler , Xiaocheng Shang

We analyze a specific class of random systems that are driven by a symmetric L\'{e}vy stable noise. In view of the L\'{e}vy noise sensitivity to the confining "potential landscape" where jumps take place (in other words, to environmental…

Statistical Mechanics · Physics 2015-06-11 M. Zaba , P. Garbaczewski , V. Stephanovich

Although stable solutions of dynamical systems are typically considered more important than unstable ones, unstable solutions have a critical role in the dynamical integrity of stable solutions. In fact, usually, basins of attraction…

Chaotic Dynamics · Physics 2024-08-15 Giuseppe Habib

This paper proposes a novel approach to adaptive step sizes in stochastic gradient descent (SGD) by utilizing quantities that we have identified as numerically traceable -- the Lipschitz constant for gradients and a concept of the local…

Optimization and Control · Mathematics 2024-09-19 Frederik Köhne , Leonie Kreis , Anton Schiela , Roland Herzog

This work is concerned with the dynamics of a class of slow-fast stochastic dynamical systems with non-Gaussian stable L\'evy noise with a scale parameter. Slow manifolds with exponentially tracking property are constructed, eliminating the…

Dynamical Systems · Mathematics 2017-07-18 Shenglan Yuan , Jianyu Hu , Xianming Liu , Jinqiao Duan

Transition pathways of stochastic dynamical systems are typically approximated by instantons. Here we show, using a dynamical system containing two competing pathways, that at low-to-intermediate temperatures, instantons can fail to capture…

Statistical Mechanics · Physics 2022-08-05 Lukas Kikuchi , Ronojoy Adhikari , Julian Kappler

Lattice simulations of non-zero density QCD introduce the so-called sign problem (complex or negative probabilities), which invalidates importance sampling methods. To circumvent this, we use the Complex Langevin Equation (CLE), to measure…

High Energy Physics - Lattice · Physics 2023-03-01 Michael W. Hansen , Dénes Sexty

We present a theoretical analysis of some popular adaptive Stochastic Gradient Descent (SGD) methods in the small learning rate regime. Using the stochastic modified equations framework introduced by Li et al., we derive effective…

Machine Learning · Statistics 2025-09-29 Luca Callisti , Marco Romito , Francesco Triggiano

The physical significance of the stochastic processes associated to the generalized Gibbs ensembles is scrutinized here with special attention to the thermodynamic fluctuations of small systems. The contact with the environment produces an…

Statistical Mechanics · Physics 2024-09-04 Amilcare Porporato , Salvatore Calabrese , Lamberto Rondoni

Monte Carlo sampling for Bayesian posterior inference is a common approach used in machine learning. The Markov Chain Monte Carlo procedures that are used are often discrete-time analogues of associated stochastic differential equations…

Machine Learning · Statistics 2020-02-14 Xiaocheng Shang , Zhanxing Zhu , Benedict Leimkuhler , Amos J. Storkey

The properties of molecules and materials containing light nuclei are affected by their quantum mechanical nature. Modelling these quantum nuclear effects accurately requires computationally demanding path integral techniques. Considerable…

Chemical Physics · Physics 2020-04-22 Venkat Kapil , David M. Wilkins , Jinggang Lan , Michele Ceriotti

We present the reweighted complex Langevin method, which enlarges the applicability range of the complex Langevin method by reweighting the complex trajectories. In this reweighting procedure both the auxiliary and target ensembles have a…

High Energy Physics - Lattice · Physics 2017-01-06 Jacques Bloch , Johannes Meisinger , Sebastian Schmalzbauer

We conduct a comprehensive investigation into the dynamics of gradient descent using large-order constant step-sizes in the context of quadratic regression models. Within this framework, we reveal that the dynamics can be encapsulated by a…

Machine Learning · Computer Science 2023-10-04 Xuxing Chen , Krishnakumar Balasubramanian , Promit Ghosal , Bhavya Agrawalla

We analyst in detail a new approach to the monitoring and forecasting of the onset of transitions in high dimensional complex systems (see Phys. Rev. Lett . vol. 113, 264102 (2014)) by application to the Tangled Nature Model of evolutionary…

Adaptation and Self-Organizing Systems · Physics 2015-08-03 Duccio Piovani , Jelena Grujic , Henrik Jeldtoft Jensen

In this work an approximated path integral model describing the dynamics of a inextensible chain is presented. To this purpose, the nonlinear constraints which enforce the property of inextensibility of the chain are relaxed and are just…

Statistical Mechanics · Physics 2010-09-20 Franco Ferrari , Maciej Pyrka

We propose an adaptive biasing algorithm aimed at enhancing the sampling of multimodal measures by Langevin dynamics. The underlying idea consists in generalizing the standard adaptive biasing force method commonly used in conjunction with…

Analysis of PDEs · Mathematics 2010-08-23 Chris Chipot , Tony Lelièvre

Properties of systems driven by white non-Gaussian noises can be very different from these systems driven by the white Gaussian noise. We investigate stationary probability densities for systems driven by $\alpha$-stable L\'evy type noises,…

Statistical Mechanics · Physics 2009-11-13 B. Dybiec , E. Gudowska-Nowak , I. M. Sokolov

In the landscape of approaches toward the simulation of Lattice Models with complex action the Complex Langevin (CL) appears as a straightforward method with a simple, well defined setup. Its applicability, however, is controlled by certain…

High Energy Physics - Lattice · Physics 2018-04-18 Gert Aarts , Kirill Boguslavski , Manuel Scherzer , Erhard Seiler , Dénes Sexty , Ion-Olimpiu Stamatescu

Formulated is a new systematic method for obtaining higher order corrections in numerical simulation of stochastic differential equations (SDEs), i.e., Langevin equations. Random walk step algorithms within a given order of finite $\Delta…

High Energy Physics - Lattice · Physics 2009-10-28 H. Nakajima , S. Furui
‹ Prev 1 4 5 6 7 8 10 Next ›