Physical Review最新文献_第10页

Propagation of generalized Korteweg–de Vries solitons along large-scale waves 广义Korteweg-de Vries孤子沿大尺度波的传播

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054205

A. M. Kamchatnov, D. V. Shaykin

引用次数: 0

Effect of collaborative-filtering-based recommendation algorithms on opinion polarization 基于协同过滤的推荐算法对意见极化的影响

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054304

Alessandro Bellina, Claudio Castellano, Paul Pineau, Giulio Iannelli, Giordano De Marzo

{"title":"Effect of collaborative-filtering-based recommendation algorithms on opinion polarization","authors":"Alessandro Bellina, Claudio Castellano, Paul Pineau, Giulio Iannelli, Giordano De Marzo","doi":"10.1103/physreve.108.054304","DOIUrl":"https://doi.org/10.1103/physreve.108.054304","url":null,"abstract":"A central role in shaping the experience of users online is played by recommendation algorithms. On the one hand they help retrieving content that best suits users taste, but on the other hand they may give rise to the so-called ``filter bubble'' effect, favoring the rise of polarization. In the present paper we study how a user-user collaborative-filtering algorithm affects the behavior of a group of agents repeatedly exposed to it. By means of analytical and numerical techniques we show how the system stationary state depends on the strength of the similarity and popularity biases, quantifying respectively the weight given to the most similar users and to the best rated items. In particular, we derive a phase diagram of the model, where we observe three distinct phases: disorder, consensus, and polarization. In the last users spontaneously split into different groups, each focused on a single item. We identify, at the boundary between the disorder and polarization phases, a region where recommendations are nontrivially personalized without leading to filter bubbles. Finally, we show that our model well reproduces the behavior of users on the online music platform last.fm. This analysis paves the way to a systematic analysis of recommendation algorithms by means of statistical physics methods and opens the possibility of devising less polarizing recommendation algorithms.","PeriodicalId":20121,"journal":{"name":"Physical Review","volume":"92 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135679117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analytical approach to higher-order correlation functions in U(1) symmetric systems U(1)对称系统中高阶相关函数的解析方法

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreva.108.053703

Zhi-Guang Lu, Cheng Shang, Ying Wu, Xin-You Lü

引用次数: 1

Numerical simulations of granular dam break: Comparison between discrete element, Navier-Stokes, and thin-layer models 颗粒溃坝的数值模拟:离散元、Navier-Stokes和薄层模型的比较

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054902

Hugo A. Martin, Marc Peruzzetto, Sylvain Viroulet, Anne Mangeney, Pierre-Yves Lagrée, Stéphane Popinet, Bertrand Maury, Aline Lefebvre-Lepot, Yvon Maday, François Bouchut

{"title":"Numerical simulations of granular dam break: Comparison between discrete element, Navier-Stokes, and thin-layer models","authors":"Hugo A. Martin, Marc Peruzzetto, Sylvain Viroulet, Anne Mangeney, Pierre-Yves Lagrée, Stéphane Popinet, Bertrand Maury, Aline Lefebvre-Lepot, Yvon Maday, François Bouchut","doi":"10.1103/physreve.108.054902","DOIUrl":"https://doi.org/10.1103/physreve.108.054902","url":null,"abstract":"Granular flows occur in various contexts, including laboratory experiments, industrial processes, and natural geophysical flows. To investigate their dynamics, different kinds of physically based models have been developed. These models can be characterized by the length scale at which dynamic processes are described. Discrete models use a microscopic scale to individually model each grain, Navier-Stokes models use a mesoscopic scale to consider elementary volumes of grains, and thin-layer models use a macroscopic scale to model the dynamics of elementary columns of fluids. In each case, the derivation of the associated equations is well-known. However, few studies focus on the extent to which these modeling solutions yield mutually coherent results. In this article, we compare the simulations of a granular dam break on a horizontal or inclined planes for the discrete model convex optimization contact dynamics (COCD), the Navier-Stokes model Basilisk, and the thin-layer depth-averaged model SHALTOP. We show that, although all three models allow reproducing the temporal evolution of the free surface in the horizontal case (except for SHALTOP at the initiation), the modeled flow dynamics are significantly different, and, in particular, during the stopping phase. The stresses measured at the flow's bottom, reflecting the flow dynamics, are in relatively good agreement, but significant variations are obtained with the COCD model due to complex and fast-varying granular lattices. Similar conclusions are drawn using the same rheological parameters to model a granular dam break on an inclined plane. This comparison exercise is essential for assessing the limits and uncertainties of granular flow modeling.","PeriodicalId":20121,"journal":{"name":"Physical Review","volume":"78 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135678788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamics, statistics, and task allocation of foraging ants 觅食蚁的动态、统计与任务分配

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054306

Nuoya Zhang, Ee Hou Yong

{"title":"Dynamics, statistics, and task allocation of foraging ants","authors":"Nuoya Zhang, Ee Hou Yong","doi":"10.1103/physreve.108.054306","DOIUrl":"https://doi.org/10.1103/physreve.108.054306","url":null,"abstract":"Ant foraging is one of the most fascinating examples of cooperative behavior observed in nature. It is well studied from an entomology viewpoint, but there is currently a lack of mathematical synthesis of this phenomenon. We address this by constructing an ant foraging model that incorporates simple behavioral rules within three task groups of the ant colony during foraging (foragers, transporters, and followers), pheromone trails, and memory effects. The motion of an ant is modeled as a discrete correlated random walk, with a characteristic zigzag path that is congruent with experimental data. We simulate the foraging cycle, which consists of ants searching for food, transporting food, and depositing chemical trails to recruit and orient more ants (en masse) to the food source. This allows us to gain insights into the basic mechanism of the cooperative interactions between ants and the dynamical division of labor within an ant colony during foraging to achieve optimal efficiency. We observe a disorder-order phase transition from the start to the end of a foraging process, signaling collective motion at the population level. Finally, we present a set of time delay ODEs that corroborates with numerical simulations.","PeriodicalId":20121,"journal":{"name":"Physical Review","volume":"180 1‐2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135679375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Time-delay-induced spiral chimeras on a spherical surface of globally coupled oscillators 全局耦合振子球面上的延时诱导螺旋嵌合体

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054204

Ryong-Son Kim, Chol-Ung Choe

引用次数: 0

Intercellular competitive growth dynamics with microenvironmental feedback 微环境反馈下的细胞间竞争生长动力学

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.054105

De-Ming Liu, Zhi-Xi Wu, Jian-Yue Guan

{"title":"Intercellular competitive growth dynamics with microenvironmental feedback","authors":"De-Ming Liu, Zhi-Xi Wu, Jian-Yue Guan","doi":"10.1103/physreve.108.054105","DOIUrl":"https://doi.org/10.1103/physreve.108.054105","url":null,"abstract":"Normal life activities between cells rely crucially on the homeostasis of the cellular microenvironment, but aging and cancer will upset this balance. In this paper we introduce the microenvironmental feedback mechanism to the growth dynamics of multicellular organisms, which changes the cellular competitive ability and thereby regulates the growth of multicellular organisms. We show that the presence of microenvironmental feedback can effectively delay aging, but cancer cells may grow uncontrollably due to the emergence of the tumor microenvironment (TME). We study the effect of the fraction of cancer cells relative to that of senescent cells on the feedback rate of the microenvironment on the lifespan of multicellular organisms and find that the average lifespan shortened is close to the data for non-Hodgkin's lymphoma in Canada from 1980 to 2015. We also investigate how the competitive ability of cancer cells affects the lifespan of multicellular organisms and reveal that there is an optimal value of the competitive ability of cancer cells allowing the organism to survive longest. Interestingly, the proposed microenvironmental feedback mechanism can give rise to the phenomenon of Parrondo's paradox: When the competitive ability of cancer cells switches between a too-high and a too-low value, multicellular organisms are able to live longer than in each case individually. Our results may provide helpful clues for targeted therapies aimed at the TME.","PeriodicalId":20121,"journal":{"name":"Physical Review","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135678787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Speed limit, dissipation bound, and dissipation-time trade-off in thermal relaxation processes 热弛豫过程中的速度限制、耗散边界和耗散时间权衡

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.l052103

Jie Gu

引用次数: 1

Hydrogen and hydrogenlike-ion bound states and hyperfine splittings: Finite-nuclear-size effects 氢和类氢离子束缚态和超细分裂:有限核尺寸效应

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreva.108.052804

Igor Kuzmenko, Tetyana Kuzmenko, Y. Avishai, Y. B. Band

引用次数: 0

Formation and properties of spatially inhomogeneous plasma density gratings 空间非均匀等离子体密度光栅的形成与特性

Physical Review Pub Date : 2023-11-06 DOI: 10.1103/physreve.108.055204

G. Lehmann, K. H. Spatschek

{"title":"Formation and properties of spatially inhomogeneous plasma density gratings","authors":"G. Lehmann, K. H. Spatschek","doi":"10.1103/physreve.108.055204","DOIUrl":"https://doi.org/10.1103/physreve.108.055204","url":null,"abstract":"Volume plasma density gratings receive increasing interest since, compared to solid-state optical media, they posses significantly higher damage thresholds. The gratings are produced by counterpropagating laser pulses in underdense plasma. When analyzing their optical properties, usually they are assumed to be homogeneous in space. The latter assumption, however, breaks down, especially when the gratings are produced by short high-power laser pump pulses. Then, generically the plasma grating posses an inhomogeneous envelope which results from the superposition of the pump pulses envelopes. The present paper discusses the effect of grating inhomogeneity on reflection and transmission of probe pulses. A Gaussian plasma density grating becomes an apodized grating which offers significant improvement over homogeneous gratings due to side-lobe suppression while maintaining reflectivity and a narrow bandwidth. On the other hand, the reflected probe pulses receive a chirp which depends on the spatial scale. For a Gaussian grating a cubic spectral phase appears. Numerical particle-in-cell simulations are supported by theoretical analysis based on coupled mode equations as well as an effective medium approach.","PeriodicalId":20121,"journal":{"name":"Physical Review","volume":"7 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135590257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0