发布求助
文献互助 智能选刊 最新文献

Journal of Statistical Mechanics: Theory and Experiment最新文献

筛选
英文 中文
The simplified energy landscape of the φ 4 model and the phase transition φ 4 模型的简化能谱和相变
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-09 DOI: 10.1088/1742-5468/ad5437
Fabrizio Baroni
{"title":"The simplified energy landscape of the φ 4 model and the phase transition","authors":"Fabrizio Baroni","doi":"10.1088/1742-5468/ad5437","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5437","url":null,"abstract":"The on-lattice φ4 model is a paradigmatic example of a continuous real-variable model undergoing a continuous symmetry-breaking phase transition (SBPT). Here, we study the -symmetric mean-field case without the quadratic term in the local potential. We show that the -SBPT is not affected by the quadratic term and that the potential energy landscape is greatly simplified from a geometric–topological viewpoint. In particular, only three critical points exist to confront, with a number growing as eN (N is the number of degrees of freedom) of the model with a negative quadratic term. We focus on the properties of the equipotential surfaces with the aim to deepen the link between SBPTs and the essential properties of a potential that is capable of entailing them. The results are interpreted in view of of some recent achievements regarding rigorous necessary and sufficient conditions for a -SBPT.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"166 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141576016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A supersymmetric quantum perspective on the explicit large deviations for reversible Markov jump processes, with applications to pure and random spin chains 从超对称量子视角看可逆马尔可夫跃迁过程的显式大偏差，以及对纯自旋链和随机自旋链的应用
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-09 DOI: 10.1088/1742-5468/ad526d
Cécile Monthus
{"title":"A supersymmetric quantum perspective on the explicit large deviations for reversible Markov jump processes, with applications to pure and random spin chains","authors":"Cécile Monthus","doi":"10.1088/1742-5468/ad526d","DOIUrl":"https://doi.org/10.1088/1742-5468/ad526d","url":null,"abstract":"The large deviations at various levels that are explicit for Markov jump processes satisfying detailed balance are revisited in terms of the supersymmetric quantum Hamiltonian H that can be obtained from the Markov generator via a similarity transformation. We first focus on the large deviations at level 2 for the empirical density of the configurations C seen during a trajectory over the large time window , and rewrite the explicit Donsker–Varadhan rate function as the matrix element involving the square-root ket . (The analog formula is also discussed for reversible diffusion processes as a comparison.) We then consider the explicit rate functions at higher levels, in particular for the joint probability of the empirical density and the empirical local activities characterizing the density of jumps between two configurations . Finally, the explicit rate function for the joint probability of the empirical density and of the empirical total activity that represents the total density of jumps of a long trajectory is written in terms of the two matrix elements and , where represents the off-diagonal part of the supersymmetric Hamiltonian H. This general framework is then applied to pure or random spin chains with single-spin-flip or two-spin-flip transition rates, where the supersymmetric Hamiltonian H corresponds to quantum spin chains with local interactions involving Pauli matrices of two or three neighboring sites. It is then useful to introduce the quantum density matrix associated with the empirical density in order to rewrite the various rate functions in terms of reduced density matrices involving only two or three neighboring sites.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"17 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141576017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Level statistics of the one-dimensional dimerized Hubbard model 一维二聚化哈伯德模型的电平统计
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-04 DOI: 10.1088/1742-5468/ad5270
Karin Haderlein, David J Luitz, Corinna Kollath and Ameneh Sheikhan
{"title":"Level statistics of the one-dimensional dimerized Hubbard model","authors":"Karin Haderlein, David J Luitz, Corinna Kollath and Ameneh Sheikhan","doi":"10.1088/1742-5468/ad5270","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5270","url":null,"abstract":"The statistical properties of level spacings provide valuable insights into the dynamical properties of a many-body quantum systems. We investigate the level statistics of the Fermi–Hubbard model with dimerized hopping amplitude and find that after taking into account translation, reflection, spin and η pairing symmetries to isolate irreducible blocks of the Hamiltonian, the level spacings in the limit of large system sizes follow the distribution expected for hermitian random matrices from the Gaussian orthogonal ensemble. We show this by analyzing the distribution of the ratios of consecutive level spacings in this system, its cumulative distribution and quantify the deviations of the distributions using their mean, standard deviation and skewness.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"11 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Many-sided Poisson–Voronoi cells with only Gabriel neighbors 只有加布里埃尔邻居的多面泊松-沃罗诺伊小区
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-02 DOI: 10.1088/1742-5468/ad5434
H J Hilhorst
{"title":"Many-sided Poisson–Voronoi cells with only Gabriel neighbors","authors":"H J Hilhorst","doi":"10.1088/1742-5468/ad5434","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5434","url":null,"abstract":"Let be the probability for a planar Poisson–Voronoi cell to be n-sided and have only Gabriel neighbors. Using an exact coordinate transformation followed by scaling arguments and a mean-field type calculation, we obtain the asymptotic expansion of in the limit of large n. We determine several statistical properties of a many-sided cell obeying this ‘Gabriel condition.’ In particular, the cell perimeter, when parametrized as a function of the polar angle θ, behaves as a Brownian bridge on the interval . We point out similarities and differences with related problems in random geometry.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"49 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Extraction of nonlinearity in neural networks with Koopman operator 利用库普曼算子提取神经网络中的非线性问题
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-02 DOI: 10.1088/1742-5468/ad5713
Naoki Sugishita, Kayo Kinjo and Jun Ohkubo
{"title":"Extraction of nonlinearity in neural networks with Koopman operator","authors":"Naoki Sugishita, Kayo Kinjo and Jun Ohkubo","doi":"10.1088/1742-5468/ad5713","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5713","url":null,"abstract":"Nonlinearity plays a crucial role in deep neural networks. In this paper, we investigate the degree to which the nonlinearity of the neural network is essential. For this purpose, we employ the Koopman operator, extended dynamic mode decomposition, and the tensor-train format. The Koopman operator approach has been recently developed in physics and nonlinear sciences; the Koopman operator deals with the time evolution in the observable space instead of the state space. Since we can replace the nonlinearity in the state space with the linearity in the observable space, it is a hopeful candidate for understanding complex behavior in nonlinear systems. Here, we analyze learned neural networks for the classification problems. As a result, the replacement of the nonlinear middle layers with the Koopman matrix yields enough accuracy in numerical experiments. In addition, we confirm that the pruning of the Koopman matrix gives sufficient accuracy even at high compression ratios. These results indicate the possibility of extracting some features in the neural networks with the Koopman operator approach.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"31 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Integrated modeling of crowd groups based on spatial distribution of members 基于成员空间分布的人群群体综合建模
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-02 DOI: 10.1088/1742-5468/ad5712
Bin Yu, Dongxiu Ou and Jianhong Ye
{"title":"Integrated modeling of crowd groups based on spatial distribution of members","authors":"Bin Yu, Dongxiu Ou and Jianhong Ye","doi":"10.1088/1742-5468/ad5712","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5712","url":null,"abstract":"An integrated framework supporting both leader-follower and leaderless groups is proposed. The concept of subgroup is supported so that chains of groups can exist. This allows to model complicated group relationships in crowd simulations. To model group related dynamics, rules are proposed. A detailed explanation of implementation of these rules is given. To validate the proposed framework, two sets of numerical experiments are conducted, using experimental data collected by previous researchers. In one set of experiments, small leader-follower groups without subgroups are considered. In the other set, groups are leaderless and can be small or large with zero or more subgroups. The impact of crowd groups on fundamental diagrams is also experimented. The conducted experiments indicate that the proposed framework can reproduce results that are quite comparable to practical values, thus the framework’s efficacy is validated within a certain range.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"194 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Exact solutions to macroscopic fluctuation theory through classical integrable systems 通过经典可积分系统实现宏观波动理论的精确解
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-07-02 DOI: 10.1088/1742-5468/ad485e
Kirone Mallick, Hiroki Moriya and Tomohiro Sasamoto
{"title":"Exact solutions to macroscopic fluctuation theory through classical integrable systems","authors":"Kirone Mallick, Hiroki Moriya and Tomohiro Sasamoto","doi":"10.1088/1742-5468/ad485e","DOIUrl":"https://doi.org/10.1088/1742-5468/ad485e","url":null,"abstract":"We give a short overview of recent developments in exact solutions for macroscopic fluctuation theory by using connections to classical integrable systems. A calculation of the cumulant generating function for a tagged particle is also given, agreeing with a previous result obtained from a microscopic analysis.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"142 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Blackbody heat capacity at constant pressure 恒压下的黑体热容量
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-06-30 DOI: 10.1088/1742-5468/ad4e2b
E S Moreira Jr
{"title":"Blackbody heat capacity at constant pressure","authors":"E S Moreira Jr","doi":"10.1088/1742-5468/ad4e2b","DOIUrl":"https://doi.org/10.1088/1742-5468/ad4e2b","url":null,"abstract":"At first glance, the title of this work seems to be improper. And the reason is well known. Since blackbody pressure depends only on temperature, one cannot take the derivative of the thermodynamic quantities with respect to one of them, keeping the other constant. That is, the heat capacity at constant pressure, CP, as well as, the coefficient of thermal expansion, α, and the isothermal compressibility, κT, are ill-defined quantities. This work will show that when the perfect conducting nature of the walls of a blackbody cavity is taken into account, CP, α and κT are in fact well defined, and they are related by the usual thermodynamic relations, as expected. Two geometries will be considered, namely, a spherical shell and a cubic box. It will be shown that CP, α and κT depend very much on the geometry of the cavity. Issues regarding thermodynamic stability will be addressed, revealing that they also depend on the cavity’s geometry. It is argued that these findings may be amenable to experimental verification.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"4 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of the effect of obstacles on evacuation efficiency in emergencies 障碍物对紧急情况下疏散效率的影响分析
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-06-26 DOI: 10.1088/1742-5468/ad4e2c
Heng Niu, Yuanyuan Zhang, Liang Li, Yanbin Han, Qingtao Hou and Sijie Niu
{"title":"Analysis of the effect of obstacles on evacuation efficiency in emergencies","authors":"Heng Niu, Yuanyuan Zhang, Liang Li, Yanbin Han, Qingtao Hou and Sijie Niu","doi":"10.1088/1742-5468/ad4e2c","DOIUrl":"https://doi.org/10.1088/1742-5468/ad4e2c","url":null,"abstract":"Congestion is one of the factors that affects evacuation efficiency in emergencies. In this study, we focus on shortening the total evacuation time (TET) by setting obstacles near the exit. For this purpose, we add a probability-based obstacle avoidance strategy to modify the original social force model to simulate pedestrians’ obstacle avoidance behaviour. Using the model, we analyse the influence of the number of obstacles, their position and their distance to the wall with the exit on the TET. In addition, we discuss the relationship between the average density at the exit and the TET, which shows that crowd diversion is an effective method to alleviate congestion and shorten the TET. The simulation results show that the evacuation efficiency can be improved by reasonably setting obstacles near the exit. This study can provide some guidance for the management of crowds during emergency evacuations.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"80 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Local detailed balance for active particle models 主动粒子模型的局部详细平衡
IF 2.4 3区 物理与天体物理
Journal of Statistical Mechanics: Theory and Experiment Pub Date : 2024-06-25 DOI: 10.1088/1742-5468/ad5435
Faezeh Khodabandehlou and Christian Maes
{"title":"Local detailed balance for active particle models","authors":"Faezeh Khodabandehlou and Christian Maes","doi":"10.1088/1742-5468/ad5435","DOIUrl":"https://doi.org/10.1088/1742-5468/ad5435","url":null,"abstract":"Starting from a Huxley-type model for an agitated vibrational mode, we propose an embedding of standard active particle models in terms of two-temperature processes. One temperature refers to an ambient thermal bath, and the other temperature effectively describes ‘hot spots,’ i.e. systems with few degrees of freedom showing important population homogenization or even inversion of energy levels as a result of activation. That setup admits to quantitatively specifying the resulting nonequilibrium driving, rendering local detailed balance to active particle models, and making easy contact with thermodynamic features. In addition, we observe that the shape transition in the steady low-temperature behavior of run-and-tumble particles (with the interesting emergence of edge states at high persistence) is stable and occurs for all temperature differences, including close to equilibrium.","PeriodicalId":17207,"journal":{"name":"Journal of Statistical Mechanics: Theory and Experiment","volume":"121 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141517118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信