Journal of Physics Complexity最新文献_第8页

Spatial patterns and biodiversity in rock-paper-scissors models with regional unevenness 具有区域不均匀性的石头剪刀布模型的空间格局与生物多样性

IF 2.7

Journal of Physics Complexity Pub Date : 2023-05-15 DOI: 10.1088/2632-072X/acd610

J. Menezes, M. Tenorio

{"title":"Spatial patterns and biodiversity in rock-paper-scissors models with regional unevenness","authors":"J. Menezes, M. Tenorio","doi":"10.1088/2632-072X/acd610","DOIUrl":"https://doi.org/10.1088/2632-072X/acd610","url":null,"abstract":"Climate changes may affect ecosystems destabilising relationships among species. We investigate the spatial rock-paper-scissors models with a regional unevenness that reduces the selection capacity of organisms of one species. Our results show that the regionally weak species predominates in the local ecosystem, while spiral patterns appear far from the region, where individuals of every species play the rock-paper-scissors game with the same strength. Because the weak species controls all local territory, it is attractive for the other species to enter the local ecosystem to conquer the territory. However, our stochastic simulations show that the transitory waves formed when organisms of the strong species reach the region are quickly destroyed because of local strength unbalance in the selection game rules. Computing the effect of the topology on population dynamics, we find that the prevalence of the weak species becomes more significant if the transition of the selection capacity to the area of uneven rock-paper-scissors rules is smooth. Finally, our findings show that the biodiversity loss due to the arising of regional unevenness is minimised if the transition to the region where the cyclic game is unbalanced is abrupt. Our results may be helpful to biologists in comprehending the consequences of changes in the environmental conditions on species coexistence and spatial patterns in complex systems.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47541588","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

Mitigation of adversarial attacks on voter model dynamics by network heterogeneity 利用网络异质性缓解对选民模型动力学的对抗性攻击

IF 2.7

Journal of Physics Complexity Pub Date : 2023-05-04 DOI: 10.1088/2632-072X/acd296

Katsumi Chiyomaru, Kazuhiro Takemoto

{"title":"Mitigation of adversarial attacks on voter model dynamics by network heterogeneity","authors":"Katsumi Chiyomaru, Kazuhiro Takemoto","doi":"10.1088/2632-072X/acd296","DOIUrl":"https://doi.org/10.1088/2632-072X/acd296","url":null,"abstract":"Voter model dynamics in complex networks are vulnerable to adversarial attacks. In particular, the voting outcome can be inverted by adding extremely small perturbations that are strategically generated in social networks, even when one opinion is dominant over the other. However, the mitigation of adversarial attacks on the voter model dynamics in complex networks has not been thoroughly investigated. Thus, we examined network structures that could mitigate adversarial attacks using model networks and real-world networks, considering that the network structure affects the voter model dynamics. Numerical simulations demonstrated that the heterogeneity of node degrees in the networks (degree heterogeneity) significantly mitigates adversarial attacks. In particular, for complex networks with a power-law degree distribution P(k)∼k−γ , the mitigation effect is significant for γ⩽3 . However, the mitigation effect of the degree heterogeneity was relatively weak for large and dense networks. The degree correlation and clustering in the networks exhibited almost no mitigation effect. The results enhance our understanding of how opinion dynamics and collective decision-making are distorted in social networks and may be useful for considering defense strategies against adversarial attacks.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43411827","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

Estimating prediction horizon of reservoir computer on L63 system when observed variables are incomplete L63系统观测变量不完全时储层计算机预测层位估计

IF 2.7

Journal of Physics Complexity Pub Date : 2023-05-03 DOI: 10.1088/2632-072X/acd21c

Yu Huang, Zuntao Fu

引用次数: 0

Neglecting complex network structures underestimates delays in a large-capital project 忽略复杂的网络结构低估了大型项目的延迟

IF 2.7

Journal of Physics Complexity Pub Date : 2023-04-20 DOI: 10.1088/2632-072X/accef0

C. Ellinas, D. Avraam, C. Nicolaides

引用次数: 0

Smallworldness in hypergraphs 超图中的小世界性

IF 2.7

Journal of Physics Complexity Pub Date : 2023-04-18 DOI: 10.1088/2632-072X/acf430

Tanu Raghav, S. Boccaletti, S. Jalan

引用次数: 0

Effects of active noise on transition-path dynamics 有源噪声对过渡路径动力学的影响

IF 2.7

Journal of Physics Complexity Pub Date : 2023-04-12 DOI: 10.1088/2632-072X/accc69

K. Goswami, R. Metzler

{"title":"Effects of active noise on transition-path dynamics","authors":"K. Goswami, R. Metzler","doi":"10.1088/2632-072X/accc69","DOIUrl":"https://doi.org/10.1088/2632-072X/accc69","url":null,"abstract":"We propose an extension of the existing model describing a biomolecular reaction such as protein folding or ligand binding which is usually visualised as the barrier crossing of a diffusing particle in a double-well potential. In addition to the thermal noise, an active noise modelled in terms of an Ornstein–Uhlenbeck process is introduced to the dynamics. Within this framework, we investigate the transition-path properties of an underdamped particle surmounting an energy barrier, and we show explicitly how these properties are affected by the activity and persistence of the particle. Our theoretical study suggests that an active particle can cross the barrier at comparatively shorter timescales by lowering the (effective) barrier height. In particular, we study how the persistence time of the active force alters the transition-path time (TPT) at different friction limits. Interestingly, in one of our models we find a nonmonotonic behaviour of the TPT which is absent in the overdamped limit. The framework presented here can be useful in designing a reaction in a non-equilibrium environment, particularly inside a living biological cell in which active fluctuations keep the system out of equilibrium.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42356466","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: 3

Sparse block-structured random matrices: universality 稀疏块结构随机矩阵:通用性

IF 2.7

Journal of Physics Complexity Pub Date : 2023-03-23 DOI: 10.1088/2632-072X/acc71a

G. M. Cicuta, M. Pernici

引用次数: 0

Online identity as a collective labeling process 网络身份作为一个集体标签的过程

IF 2.7

Journal of Physics Complexity Pub Date : 2023-03-21 DOI: 10.1088/2632-072X/acc62c

Alexander T. J. Barron, Marijn ten Thij, J. Bollen

{"title":"Online identity as a collective labeling process","authors":"Alexander T. J. Barron, Marijn ten Thij, J. Bollen","doi":"10.1088/2632-072X/acc62c","DOIUrl":"https://doi.org/10.1088/2632-072X/acc62c","url":null,"abstract":"Expressing identity socially involves a balance between conformity and innovation. One can adopt existing labels to express belonging to a certain community or introduce new labels to express an individual sense of identity. In such a process of co-creation, the existing identity labels of a community shape one’s sense of identity, while individual expression changes that of a community. Social media has introduced new opportunities to study the expression of collective identity. Here we study the group behavior of individuals defining their identities with hashtag self-labels in their Twitter profiles from mid-2017 through 2019. These timelines of personal self-labeling show behavior incorporating innovation, conservation, and social conformity when defining self. We show that the collective co-labeling of popular concepts in the context of identity, such as #resist and #maga, follow the dynamics of a modified Yule–Simon model balancing novelty and conformity. The dynamics of identity expression resemble the collective tagging processes of folksonomies, indicating a similarity between the collective tagging of external objects and the collective labeling of ourselves. Our work underpins a better understanding of how online environments mediate the evolution of collective identity which plays an increasingly important role in the establishment of community values and identity politics.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44749280","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

Information parity increases on functional brain networks under influence of a psychedelic substance 在迷幻物质的影响下，大脑功能网络的信息平价增加

IF 2.7

Journal of Physics Complexity Pub Date : 2023-03-07 DOI: 10.1088/2632-072X/acc22b

A. Viol, G. Viswanathan, Oleksandra Soldatkina, Fernanda Palhano-Fontes, H. Onias, D. D. de Araujo, Philipp Hoevel

{"title":"Information parity increases on functional brain networks under influence of a psychedelic substance","authors":"A. Viol, G. Viswanathan, Oleksandra Soldatkina, Fernanda Palhano-Fontes, H. Onias, D. D. de Araujo, Philipp Hoevel","doi":"10.1088/2632-072X/acc22b","DOIUrl":"https://doi.org/10.1088/2632-072X/acc22b","url":null,"abstract":"The physical basis of consciousness is one of the most intriguing open questions that contemporary science aims to solve. By approaching the brain as an interactive information system, complex network theory has greatly contributed to understand brain process in different states of mind. We study a non-ordinary state of mind by comparing resting-state functional brain networks of individuals in two different conditions: before and after the ingestion of the psychedelic brew Ayahuasca. In order to quantify the functional, statistical symmetries between brain region connectivity, we calculate the pairwise information parity of the functional brain networks. Unlike the usual approach to quantitative network analysis that considers only local or global scales, information parity instead quantifies pairwise statistical similarities over the entire network structure. We find an increase in the average information parity on brain networks of individuals under psychedelic influences. Notably, the information parity between regions from the limbic system and frontal cortex is consistently higher for all the individuals while under the psychedelic influence. These findings suggest that the resemblance of statistical influences between pair of brain regions activities tends to increase under Ayahuasca effects. This could be interpreted as a mechanism to maintain the network functional resilience.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42305600","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: 1

Growing inequality in systems showing Zipf’s law 系统中不断增长的不平等体现了齐夫定律

IF 2.7

Journal of Physics Complexity Pub Date : 2023-03-02 DOI: 10.1088/2632-072X/acc0c1

Giordano De Marzo, F. Attili, L. Pietronero

{"title":"Growing inequality in systems showing Zipf’s law","authors":"Giordano De Marzo, F. Attili, L. Pietronero","doi":"10.1088/2632-072X/acc0c1","DOIUrl":"https://doi.org/10.1088/2632-072X/acc0c1","url":null,"abstract":"A central problem in economics and statistics is the assessment of income or wealth inequality starting from empirical data. Here we focus on the behavior of Gini index, one of the most used inequality measures, in presence of Zipf’s law, a situation which occurs in many complex financial and economical systems. First, we show that the application of asymptotic formulas to finite size systems always leads to an overestimation of inequality. We thus compute finite size corrections and we show that depending on Zipf’s exponent two distinct regimes can be observed: low inequality, where Gini index is less than one and maximal inequality, where Gini index asymptotically tends to its maximal value one. In both cases, the inequality of an expanding system slowly increases just as effect of growth, with a scaling never faster than the inverse of the size. We test our computations on two real systems, US cities and the cryptocurrency market, observing in both cases an increase of inequality that is completely explained by Zipf’s law and the systems expanding. This shows that in growing complex systems finite size effects must be considered in order to properly assess if inequality is increasing due to natural growth processes or if it is produced by a change in the economical structure of the systems. Finally we discuss how such effects must be carefully considered when analyzing survey data.","PeriodicalId":53211,"journal":{"name":"Journal of Physics Complexity","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43345277","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: 1