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Related papers: Approximation for a Toy Defective Ising Model

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This work introduces a new general approach for the numerical analysis of stable equilibria to second order mean field games systems in cases where the uniqueness of solutions may fail. For the sake of simplicity, we focus on a simple…

Analysis of PDEs · Mathematics 2024-10-30 Jules Berry , Olivier Ley , Francisco J Silva

Thermodynamic properties of the ferromagnetic Ising model on the hierarchical pentagon lattice is studied by means of the tensor network methods. The lattice consists of pentagons, where 3 or 4 of them meet at each vertex. Correlation…

Statistical Mechanics · Physics 2024-07-08 Takumi Oshima , Tomotoshi Nishino

This paper presents a homogenization framework for elastomeric metamaterials exhibiting long-range correlated fluctuation fields. Based on full-scale numerical simulations on a class of such materials, an ansatz is proposed that allows to…

Soft Condensed Matter · Physics 2018-10-29 O. Rokoš , M. M. Ameen , R. H. J. Peerlings , M. G. D. Geers

The classical transverse field Ising spin- glass model with short-range interactions is investigated beyond the mean- field approximation for a real d- dimensional lattice. We use an appropriate nontrivial modification of the Bethe- Peierls…

Disordered Systems and Neural Networks · Physics 2009-10-31 K Walasek , K Lukierska- Walasek , L De Cesare , I Rabuffo

In the first of two articles, we present here a novel mesoscopic micromagnetic approach for simulating materials composed of ferromagnetic and antiferromagnetic phases. Starting with the atomistic modeling of quasi one-dimensional systems,…

Materials Science · Physics 2023-10-02 Sergey Erokhin , Dmitry Berkov , Andreas Michels

The ground state energy and entropy of the dilute mean field Ising model is computed exactly by a single order parameter. An analogous exact solution is obtained in presence of a magnetic field with random locations. Results allow for a…

Disordered Systems and Neural Networks · Physics 2015-05-19 Maurizio Serva

We investigate the possibility to model a metasurface, defined as a zero-thickness sheet of surface polarization currents, by a thin slab, characterized by a subwavelength thickness and usual voluminal medium parameters. First, we elaborate…

Applied Physics · Physics 2020-05-05 Mojtaba Dehmollaian , Yousef Vahabzadeh , Karim Achouri , Christophe Caloz

The ferromagnetic Ising model is a model of a magnetic material and a central topic in statistical physics. It also plays a starring role in the algorithmic study of approximate counting: approximating the partition function of the…

Data Structures and Algorithms · Computer Science 2021-11-05 Charlie Carlson , Ewan Davies , Alexandra Kolla , Will Perkins

We consider a dynamic mean-field ferromagnetic model in the low-temperature regime in the neighborhood of the zero magnetization state. We study the random time it takes for the system to make a decision, i.e., to exit the neighborhood of…

Probability · Mathematics 2010-05-28 Yuri Bakhtin

This work proposes a hybrid modeling framework based on recurrent neural networks (RNNs) and the finite element (FE) method to approximate model discrepancies in time dependent, multi-fidelity problems, and use the trained hybrid models to…

Computational Engineering, Finance, and Science · Computer Science 2024-02-20 Moritz von Tresckow , Herbert De Gersem , Dimitrios Loukrezis

This work focuses on model preparation for electrostatic simulations of CAD designs to realize a rapid virtual prototyping concept. We present a boundary element method (BEM) allowing discontinuous fields between surfaces. The corresponding…

Computational Engineering, Finance, and Science · Computer Science 2024-12-13 Benjamin Marussig , Thomas Rüberg , Jürgen Zechner , Lars Kielhorn , Thomas-Peter Fries

We use the mean-field approximation to simplify the master equation for sympathetic cooling of Bosons. For the mean single-particle occupation numbers, this approach yields the same equations as the factorization assumption introduced in an…

Condensed Matter · Physics 2009-11-07 S. J. Wang , M. C. Nemes , A. N. Salgueiro , H. A. Weidenmueller

We present results of a Monte Carlo study for the ferromagnetic Ising model with long range interactions in two dimensions. This model has been simulated for a large range of interaction parameter $\sigma$ and for large sizes. We observe…

Statistical Mechanics · Physics 2012-07-06 Marco Picco

Mixed finite element methods are considered for a ferrofluid flow model with magnetization paralleled to the magnetic field. The ferrofluid model is a coupled system of the Maxwell equations and the incompressible Navier-Stokes equations.…

Numerical Analysis · Mathematics 2022-08-11 Yongke Wu , Xiaoping Xie

We consider a one dimensional ferromagnetic Ising spin system with interactions that correspond to a $1/r^2$ long range perturbation of the usual Kac model. We apply a coarse graining procedure, widely used for higher-dimensional finite…

Mathematical Physics · Physics 2015-05-19 Marzio Cassandro , Immacolata Merola , Maria Eulalia Vares

We present a resummed mean-field approximation for inferring the parameters of an Ising or a Potts model from empirical, noisy, one- and two-point correlation functions. Based on a resummation of a class of diagrams of the small correlation…

Disordered Systems and Neural Networks · Physics 2016-10-19 Hugo Jacquin , A. Rancon

The Equal Filling Approximation, a procedure widely used in mean field calculations to treat the dynamics of odd nuclei in a time reversal invariant way, is justified as the consequence of a variational principle over an average energy…

Nuclear Theory · Physics 2008-11-26 Sara Perez-Martin , L. M. Robledo

We apply to the Random Field Ising Model at zero temperature (T= 0) the perturbative loop expansion around the Bethe solution. A comparison with the standard epsilon-expansion is made, highlighting the key differences that make the new…

Disordered Systems and Neural Networks · Physics 2020-02-06 Maria Chiara Angelini , Carlo Lucibello , Giorgio Parisi , Federico Ricci-Tersenghi , Tommaso Rizzo

We use the Markov chain approximation method to construct approximations for the solution of the mean field game (MFG) with reflecting barriers studied in Bayraktar, Budhiraja, and Cohen (2017). The MFG is formulated in terms of a…

Optimization and Control · Mathematics 2018-08-28 Erhan Bayraktar , Amarjit Budhiraja , Asaf Cohen

We introduce a family of Galerkin finite element methods which are constructed via recovery operators over element-wise discontinuous approximation spaces. This new family, termed collectively as recovered finite element methods (R-FEM) has…

Numerical Analysis · Mathematics 2018-03-14 Emmanuil H. Georgoulis , Tristan Pryer