Physical Review E最新文献

{"title":"Fluid-network relations: Decay laws meet with spatial self-similarity, scale invariance, and control scaling.","authors":"Yang Tian, Pei Sun, Yizhou Xu","doi":"10.1103/PhysRevE.110.064314","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064314","url":null,"abstract":"<p><p>Diverse implicit structures of fluids have been discovered recently, providing opportunities to study the physics of fluids applying network analysis. Although considerable work has been devoted to identifying the informative network structures of fluids, we are limited to a primary stage of understanding what kinds of information these identified networks can convey about fluids. An essential question is how the mechanical properties of fluids are embodied in the topological properties of networks or vice versa. Here, we tackle this question by revealing a set of fluid-network relations that quantify the interactions between fundamental fluid-flow properties (e.g., kinetic energy and enstrophy decay laws) and defining network characteristics (e.g., spatial self-similarity, scale-invariance, and control scaling). We first analyze spatial self-similarity in its classic and generalized definitions, which reflect, respectively, whether vortical interactions or their spatial imbalance extents are self-similar in fluid flows. The deviation extents of networks from self-similar states exhibit power-law scaling behaviors with respect to fluid-flow properties, suggesting that the diversity among vortices is an indispensable basis of self-similar fluid flows. Then, the same paradigm is adopted to investigate scale-invariance using renormalization groups, which reveals that the breaking extents of scale-invariance in networks, similar to those of spatial self-similarity, follow power-law scaling with respect to fluid-flow properties. Finally, we define a control problem in networks to study the propagation of perturbations through vortical interactions over different ranges. The minimum cost of controlling vortical networks scales exponentially with range diameters (i.e., control distances), whose growth rates experience temporal decays. We show that this temporal decay speed is fully determined by fluid-flow properties in power-law scaling behaviors. In sum, all these discovered fluid-network relations sketch a picture in which we can study the implicit structures of fluids and quantify their interactions with fluid dynamics.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064314"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143365082","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":"Semi-Markov processes in open quantum systems. III. Large deviations of first-passage-time statistics.","authors":"Fei Liu, Shihao Xia, Shanhe Su","doi":"10.1103/PhysRevE.110.064145","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064145","url":null,"abstract":"<p><p>In a specific class of open quantum systems with finite and fixed numbers of collapsed quantum states, the semi-Markov process method is used to calculate the large deviations of the first passage time statistics. The core formula is an equation of poles, which is also applied in determining the scaled generating functions (SCGFs) of the counting statistics. For simple counting variables, the SCGFs of the first passage time statistics are derived by finding the largest modulus of the roots of this equation with respect to the z-transform parameter and then calculating its logarithm. The procedure is analogous to that of solving for the SCGFs of the counting statistics. However, for current-like variables, the method generally fails unless the equation of pole is simplified to a quadratic form. The fundamental reason for this lies in the nonuniqueness between the roots and the region of convergence for the joint transform. We illustrate these results via a resonantly driven two-level quantum system, where for several counting variables the solutions to the SCGFs of the first passage time are analytically obtained. Furthermore, we apply these functions to investigate quantum violations of the classical kinetic and thermodynamic uncertainty relations.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064145"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143365095","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":"Surfing droplets on nanoscopic films driven by surface acoustic waves.","authors":"N S Satpathi, L Malik, S Nandy, T Sujith, L Y Yeo, A K Sen","doi":"10.1103/PhysRevE.110.065108","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.065108","url":null,"abstract":"<p><p>Formation of micron-sized droplets on open surfaces continues to remain a challenge in microfluidics. The problem is even stiffer for highly spreading liquids. Here, we report the formation of microdroplets from a nanoscopically thick film of low surface tension and low-viscosity liquid following its spreading under high-frequency nanoscale acoustic wave excitation. Uniquely, these droplets are observed to \"surf\" on a thin air layer atop the liquid film along the direction of the acoustic wave. Using theoretical scaling and numerical simulations we explore this remarkable behavior and show that the droplet generates via shear-driven pinch off from spatially periodic fluid protrusions in the film, specified by the acoustic excitation wavelength in the solid (λ_{SAW}). We also predict the drop size (d_{d}) and noncoalesced drop velocity (U_{d}) from theory and find an excellent match with experiments. Further, the drop \"surfing\" dynamics is found to be a consequence of the acoustic radiation pressure imposed on the droplets as the wave is transmitted through the film and into the overlying air phase.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-2","pages":"065108"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366730","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":"Zero-temperature Monte Carlo simulations of two-dimensional quantum spin glasses guided by neural network states.","authors":"L Brodoloni, S Pilati","doi":"10.1103/PhysRevE.110.065305","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.065305","url":null,"abstract":"<p><p>A continuous-time projection quantum Monte Carlo algorithm is employed to simulate the ground state of a short-range quantum spin-glass model, namely, the two-dimensional Edwards-Anderson Hamiltonian with transverse field, featuring Gaussian nearest-neighbor couplings. We numerically demonstrate that guiding wave functions based on self-learned neural networks suppress the population control bias below modest statistical uncertainties, at least up to a hundred spins. By projecting a two-fold replicated Hamiltonian, the spin overlap is determined. A finite-size scaling analysis is performed to estimate the critical transverse field where the spin-glass transition occurs, as well as the critical exponents of the correlation length and the spin-glass susceptibility. For the latter two, good agreement is found with recent estimates from the literature for different random couplings. We also address the spin-overlap distribution within the spin-glass phase, finding that, for the workable system sizes, it displays a nontrivial double-peak shape with large weight at zero overlap.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-2","pages":"065305"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366742","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":"Biophysical model for joint analysis of chromatin and RNA sequencing data.","authors":"Catherine Felce, Gennady Gorin, Lior Pachter","doi":"10.1103/PhysRevE.110.064405","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064405","url":null,"abstract":"<p><p>The assay for transposase-accessible chromatin using sequencing (ATAC-seq) can be used to identify open chromatin regions, providing complementary information to RNA-seq which measures gene expression by sequencing. Single-cell multiome methods offer the possibility of measuring both modalities simultaneously in cells, raising the question of how to analyze them jointly, and also the extent to which the information they provide is better than unregistered data, where single-cell ATAC-seq and single-cell RNA-seq are performed on the same sample, but on different cells. We propose and motivate a biophysical model for chromatin dynamics and subsequent transcription that can be used to parametrize multiome data, and use it to assess the benefits of multiome data over unregistered single-cell RNA-seq and single-cell ATAC-seq. We also show that our model provides a biophysically grounded approach to the integration of chromatin accessibility data with other modalitie, and apply the model to single-cell ATAC-seq data.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064405"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366436","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":"Chaotic dynamics in a galactic multipolar halo with a compact primary.","authors":"Yeasin Ali, Suparna Roychowdhury","doi":"10.1103/PhysRevE.110.064202","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064202","url":null,"abstract":"<p><p>Observational evidence strongly supports the existence of a Super Massive Black Hole at the Galactic center, surrounded by dense stellar clusters. Modeling galactic centers with intricate structures like shells and rings pose challenges, prompting the use of simplified models such as a spherical monopole potential with a multipolar halo mass distribution. This approach, employing a multipolar expansion model, provides versatility for numerical analyses, revealing the complex dynamics of stars in this region. Pseudopotentials like Paczynsky-Wiita and Artemova-Bjornsson-Novikov are utilized to simulate the impacts of strong gravity from nonrotating and rotating compact objects respectively, elucidating their influence on stellar dynamics. Chaos naturally arises due to noncentral forces, visualized using the Poincaré section technique. Of particular importance is the utilization of the Smaller Alignment Index (SALI), a powerful nonlinear dynamical tool, which categorizes particle orbits as escaping, regular, sticky, or chaotic. We exhaustively examine all combinations of multipolar moments up to the octupolar term along with spin using this tool, which had not been studied earlier. SALI provides a straightforward yet efficient method for assessing the interplay between the system's different multipolar moments, their combinations, and spin. Thus, our findings offer insights into the dynamics of compact objects enshrouded in a halo mass distribution and lay the groundwork for understanding complex astrophysical systems in galactic centers.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064202"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366457","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":"Run-and-tumble particle with saturating rates.","authors":"Kavita Jain, Sakuntala Chatterjee","doi":"10.1103/PhysRevE.110.064110","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064110","url":null,"abstract":"<p><p>We consider a run-and-tumble particle whose speed and tumbling rate are space dependent on an infinite line. Unlike most of the previous work on such models, here we make the physical assumption that at large distances, these rates saturate to a constant. For our choice of rate functions, we show that a stationary state exists, and the exact steady-state distribution decays exponentially or faster and can be unimodal or bimodal. The effect of boundedness of rates is seen in the mean-squared displacement of the particle that displays qualitative features different from those observed in the previous studies where it approaches the stationary-state value monotonically in time; in contrast, here we find that if the initial position of the particle is sufficiently far from the origin, then the variance in its position either varies nonmonotonically or plateaus before reaching the stationary state. These results are captured quantitatively by the exact solution of the Green's function when the particle has uniform speed but the tumbling rates change as a step function in space; the insights provided by this limiting case are found to be consistent with the numerical results for the general model.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064110"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366476","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":"Criticality in the duration of the quasistationary state of the d-dimensional α-Heisenberg ferromagnet.","authors":"Antonio Rodríguez, Fernando D Nobre, Constantino Tsallis","doi":"10.1103/PhysRevE.110.064131","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064131","url":null,"abstract":"<p><p>The duration of the quasistationary states (QSSs) emerging in the d-dimensional classical inertial α-Heisenberg model, i.e., N three-dimensional rotators whose interactions decay with distance r_{ij} as 1/r_{ij}^{α} (α≥0), is studied through first-principle molecular dynamics. These QSSs appear for the very-long-range interaction regime (0≤α/d≤1), for an average energy per rotator U<U_{c} (U_{c}=5/6), and they do not exist for U>U_{c}. They are characterized by a kinetic temperature T_{QSS}, before a crossover to a second plateau occurring at the Boltzmann-Gibbs temperature T_{BG}>T_{QSS}. We investigate here the behavior of their duration t_{QSS} when U approaches U_{c} from below, for large values of N. The QSS gradually disappears as U→U_{c}, while its duration undergoes a critical phenomenon, namely t_{QSS}∝(U_{c}-U)^{-ξ}. Universality is found for the critical exponent ξ=1.67±0.02 throughout the very-long-range interaction regime.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064131"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366497","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":"Data-driven physics-based modeling of pedestrian dynamics.","authors":"Caspar A S Pouw, Geert G M van der Vleuten, Alessandro Corbetta, Federico Toschi","doi":"10.1103/PhysRevE.110.064102","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064102","url":null,"abstract":"<p><p>Pedestrian crowds encompass a complex interplay of intentional movements aimed at reaching specific destinations, fluctuations due to personal and interpersonal variability, and interactions with each other and the environment. Previous work demonstrated the effectiveness of Langevin-like equations in capturing the statistical properties of pedestrian dynamics in simple settings, such as almost straight trajectories. However, modeling more complex dynamics, such as when multiple routes and origin destinations are involved, remains a significant challenge. In this work, we introduce a novel and generic framework to describe the dynamics of pedestrians in any geometric setting, significantly extending previous works. Our model is based on Langevin dynamics with two timescales. The fast timescale corresponds to the stochastic fluctuations present when a pedestrian is walking. The slow timescale is associated with the dynamics that a pedestrian plans to follow, thus a smoother path without stochastic fluctuations. Employing a data-driven approach inspired by statistical field theories, we learn the complex potentials directly from the data, namely a high-statistics database of real-life pedestrian trajectories. This approach makes the model generic as the potentials can be read from any trajectory data set and the underlying Langevin structure enables physics-based insights. We validate our model through a comprehensive statistical analysis, comparing simulated trajectories with actual pedestrian measurements across five complementary settings of increasing complexity, including a real-life train platform scenario, underscoring its practical societal relevance. We show that our model, by learning the effective potential, captures fluctuation statistics in the dynamics of individual pedestrians, both in dilute (no interaction with other pedestrians) as well as in dense crowds conditions (in presence of interactions). Our results can be reproduced with our generic open-source Python implementation [Pouw et al. (2024) [Software] doi:10.5281/zenodo.13362271] and validated with the supplemented data set [Pouw et al. (2024) [Dataset] doi:10.5281/zenodo.13784588]. Beyond providing fundamental insights and predictive capabilities in pedestrian dynamics, our model could be used to investigate generic active dynamics such as vehicular traffic and collective animal behavior.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064102"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366510","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":"Decentralized multiagent reinforcement learning algorithm using a cluster-synchronized laser network.","authors":"Shun Kotoku, Takatomo Mihana, André Röhm, Ryoichi Horisaki","doi":"10.1103/PhysRevE.110.064212","DOIUrl":"https://doi.org/10.1103/PhysRevE.110.064212","url":null,"abstract":"<p><p>Multiagent reinforcement learning (MARL) studies crucial principles that are applicable to a variety of fields, including wireless networking and autonomous driving. We propose a photonic-based decision-making algorithm to address one of the most fundamental problems in MARL, called the competitive multiarmed bandit (CMAB) problem. Our numerical simulations demonstrate that chaotic oscillations and cluster synchronization of optically coupled lasers, along with our proposed decentralized coupling adjustment, efficiently balance exploration and exploitation while facilitating cooperative decision making without explicitly sharing information among agents. Our study demonstrates how decentralized reinforcement learning can be achieved by exploiting complex physical processes controlled by simple algorithms.</p>","PeriodicalId":48698,"journal":{"name":"Physical Review E","volume":"110 6-1","pages":"064212"},"PeriodicalIF":2.2,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366511","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}