{"title":"Time Irreversibility in Statistical Mechanics","authors":"Dominique Levesque, Nicolas Sourlas","doi":"10.1007/s10955-025-03467-0","DOIUrl":"10.1007/s10955-025-03467-0","url":null,"abstract":"<div><p>One of the important questions in statistical mechanics is how irreversibility (time’s arrow) occurs when Newton equations of motion are time reversal invariant. One objection to irreversibility is based on Poincaré’s recursion theorem: a classical Hamiltonian confined system returns after some time, so-called Poincaré recurrence time (PRT), close to its initial configuration. Boltzmann’s reply was that for a <span>(N sim 10^{23} )</span> macroscopic number of particles, PRT is very large and exceeds the age of the universe. In this paper we compute for the first time, using molecular dynamics, a typical recurrence time <i>T</i>(<i>N</i>) for a realistic case of a gas of <i>N</i> particles. We find that <span>(T(N) sim N^z exp (y N) )</span> and determine the exponents <i>y</i> and <i>z</i> for different values of the particle density and temperature. We also compute <i>y</i> analytically using Boltzmann’s hypotheses. We find an excellent agreement with the numerical results. This agreement validates Boltzmann’s hypotheses, not yet mathematically proven. We establish that <i>T</i>(<i>N</i>) exceeds the age of the Universe for a relatively small number of particles, much smaller than <span>( 10^{23} )</span>.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 7","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145144772","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}
{"title":"Matrix Product States as Observations of Entangled Hidden Markov Models","authors":"Abdessatar Souissi","doi":"10.1007/s10955-025-03472-3","DOIUrl":"10.1007/s10955-025-03472-3","url":null,"abstract":"<div><p>This paper reveals the intrinsic structure of Matrix Product States (MPS) by establishing their deep connection to entangled hidden Markov models (EHMMs). It is demonstrated that a significant class of MPS can be derived as the outcomes of EHMMs, showcasing their underlying quantum correlations. Additionally, a lower bound is derived for the relative entropy between the EHMM-observation process and the corresponding MPS, providing a quantitative measure of their informational divergence. Conversely, it is shown that every MPS is naturally associated with an EHMM, further highlighting the interplay between these frameworks. These results are supported by illustrative examples from quantum information, emphasizing their importance in understanding entanglement, quantum correlations, and tensor network representations.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 7","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143706","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}
{"title":"Elephant Random Walk with Polynomially Decaying Steps","authors":"Yuzaburo Nakano","doi":"10.1007/s10955-025-03461-6","DOIUrl":"10.1007/s10955-025-03461-6","url":null,"abstract":"<div><p>In this paper, we introduce a variation of the elephant random walk whose steps are polynomially decaying. At each time <i>k</i>, the walker’s step size is <span>(k^{-gamma })</span> with <span>(gamma >0)</span>. We investigate effects of the step size exponent <span>(gamma )</span> and the memory parameter <span>(alpha in [-1,1])</span> on the long-time behavior of the walker. For fixed <span>(alpha )</span>, it admits phase transition from divergence to convergence (localization) at <span>(gamma _{c}(alpha )=max {alpha ,1/2})</span>. This means that large enough memory effect can shift the critical point for localization. Moreover, we obtain quantitative limit theorems which provide a detailed picture of the long-time behavior of the walker.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165620","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}
{"title":"Quantum Concentration Inequalities and Equivalence of the Thermodynamical Ensembles: An Optimal Mass Transport Approach","authors":"Giacomo De Palma, Davide Pastorello","doi":"10.1007/s10955-025-03464-3","DOIUrl":"10.1007/s10955-025-03464-3","url":null,"abstract":"<div><p>We prove new concentration inequalities for quantum spin systems which apply to any local observable measured on any product state or on any state with exponentially decaying correlations. Our results do not require the spins to be arranged in a regular lattice, and cover the case of observables that contain terms acting on spins at arbitrary distance. Moreover, we introduce a local <span>(W_1)</span> distance, which quantifies the distinguishability of two states with respect to local observables. We prove a transportation-cost inequality stating that the local <span>(W_1)</span> distance between a generic state and a state with exponentially decaying correlations is upper bounded by a function of their relative entropy. Finally, we apply such inequality to prove the equivalence between the canonical and microcanonical ensembles of quantum statistical mechanics and the weak eigenstate thermalization hypothesis for the Hamiltonians whose Gibbs states have exponentially decaying correlations.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165619","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}
{"title":"Moderate Deviation Principles for the WASEP","authors":"Linjie Zhao","doi":"10.1007/s10955-025-03470-5","DOIUrl":"10.1007/s10955-025-03470-5","url":null,"abstract":"<div><p>We study the weakly asymmetric simple exclusion process on the integer lattice. Under suitable constraints on the strength of the weak asymmetry of the dynamics, we prove moderate deviation principles for the fluctuation fields when the process starts from stationary measures. As an application, we obtain sample path moderate deviation principles for the occupation time of the process in one dimension.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164994","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}
{"title":"An Update on Lower Bounds for the Critical Values of Oriented Percolation Models","authors":"Olivier Couronné","doi":"10.1007/s10955-025-03466-1","DOIUrl":"10.1007/s10955-025-03466-1","url":null,"abstract":"<div><p>We obtain new lower bounds on the critical points for various models of oriented percolation. The method relies on establishing a stochastic domination of the percolation processes by multitype Galton-Watson trees. This approach can be applied to classical bond and site oriented percolation on <span>(mathbb {Z}^2)</span>, as well as to other lattices, such as inhomogeneous ones, and in three dimensions.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164543","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}
Márton Balázs, Sudeshna Bhattacharjee, Karambir Das, David Harper
{"title":"Road Layout in The KPZ Class","authors":"Márton Balázs, Sudeshna Bhattacharjee, Karambir Das, David Harper","doi":"10.1007/s10955-025-03460-7","DOIUrl":"10.1007/s10955-025-03460-7","url":null,"abstract":"<div><p>We propose a road layout and traffic model, based on last passage percolation (LPP). An easy naïve argument shows that coalescence of traffic trajectories is essential to be considered when observing traffic networks around us. This is a fundamental feature in first passage percolation (FPP) models where nearby geodesics naturally coalesce in search of the easiest passage through the landscape. Road designers seek the same in pursuing cost savings, hence FPP geodesics are straightforward candidates to model road layouts. Unfortunately no detailed knowledge is rigorously available on FPP geodesics. To address this, we use exponential LPP instead to build a stochastic model of road traffic and prove certain characteristics thereof. Cars start from every point of the lattice and follow half-infinite geodesics in random directions. Exponential LPP is known to be in the KPZ universality class and it is widely expected that FPP shares very similar properties, hence our findings should equally apply to FPP-based modelling. We address several traffic-related quantities of this model and compare our theorems to real life road networks.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12152071/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fractional Poisson Random Fields on (mathbb {R}^2_+)","authors":"Kuldeep Kumar Kataria, Pradeep Vishwakarma","doi":"10.1007/s10955-025-03465-2","DOIUrl":"10.1007/s10955-025-03465-2","url":null,"abstract":"<div><p>We consider a fractional Poisson random field (FPRF) on positive plane. It is defined as a process whose one dimensional distribution is the solution of a system of fractional partial differential equations. A time-changed representation for the FPRF is given in terms of the composition of Poisson random field with a bivariate random process. Some integrals of the FPRF are introduced and studied. Using the Adomian decomposition method, a closed form expression for its probability mass function is obtained in terms of the generalized Wright function. Some results related to the order statistics of random numbers of random variables are presented. Also, we introduce a generalization of Poisson random field on <span>(mathbb {R}^d_+)</span>, <span>(dge 1)</span> which reduces to the Poisson random field in a special case. Later, we define the compound fractional Poisson random field via FPRF. Moreover, a generalized version of it on <span>(mathbb {R}^d_+)</span> is discussed.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163837","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}
Dirk Erhard, Tertuliano Franco, Joedson de Jesus Santana
{"title":"A Strong Large Deviation Principle for the Empirical Measure of Random Walks","authors":"Dirk Erhard, Tertuliano Franco, Joedson de Jesus Santana","doi":"10.1007/s10955-025-03463-4","DOIUrl":"10.1007/s10955-025-03463-4","url":null,"abstract":"<div><p>In this article we show that the empirical measure of certain continuous time random walks satisfies a strong large deviation principle with respect to a topology introduced in [15] by Mukherjee and Varadhan. This topology is natural in models which exhibit an invariance with respect to spatial translations. Our result applies in particular to the case of simple random walk and complements the results obtained in [15] in which the large deviation principle has been established for the empirical measure of Brownian motion.\u0000</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145162822","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}
Sean Groathouse, Christopher Janjigian, Firas Rassoul-Agha
{"title":"Non-Existence of Non-Trivial Bi-Infinite Geodesics in Geometric Last Passage Percolation","authors":"Sean Groathouse, Christopher Janjigian, Firas Rassoul-Agha","doi":"10.1007/s10955-025-03462-5","DOIUrl":"10.1007/s10955-025-03462-5","url":null,"abstract":"<div><p>We show the non-existence of non-trivial bi-infinite geodesics in the solvable last-passage percolation model with i.i.d. geometric weights. This gives the first example of a model with discrete weights where the non-existence of non-trivial bi-infinite geodesics has been proven. Our proofs rely on the structure of the increment-stationary versions of the model, following the approach recently introduced by Balázs, Busani, and Seppäläinen. Most of our results work for a general weights distribution and we identify the two properties of the stationary distributions which would need to be shown in order to generalize the main result to a non-solvable setting.</p></div>","PeriodicalId":667,"journal":{"name":"Journal of Statistical Physics","volume":"192 6","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145162823","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}