IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0356660

Hao Peng, Zidi Wang, Yanggang Cheng, Bo Zhang, Ming Zhong, Shenghong Li, Dandan Zhao, Wei Wang

{"title":"Competitive spreading dynamics under sentinel intervention in higher-order community networks.","authors":"Hao Peng, Zidi Wang, Yanggang Cheng, Bo Zhang, Ming Zhong, Shenghong Li, Dandan Zhao, Wei Wang","doi":"10.1063/5.0356660","DOIUrl":"https://doi.org/10.1063/5.0356660","url":null,"abstract":"Misinformation spreading on social networks is jointly shaped by community structure, higher-order reinforcement, and intervention. We formulate a sentinel-triggered competitive susceptible-infected-susceptible-AB model on a simplicial complex with two equal-sized communities. Sentinels respond to local misinformation exposure by temporarily becoming truth sources, coupling local detection and corrective response with higher-order reinforcement and cross-community invasion. We derive a heterogeneous mean-field description and compare its predictions with Monte Carlo simulations. The results reveal extinction, community-localized persistence, and network-wide spreading, separated by discontinuous transitions and initial-condition-dependent hysteresis in the examined parameter ranges. Increasing the sentinel fraction or the pairwise truth-spreading strength suppresses the high-misinformation state, whereas a higher sentinel activation threshold delays the response. Intercommunity coupling promotes misinformation invasion under weak intervention but can support truth spreading when sentinel intervention is sufficiently strong. Extensions to unequal community sizes and more general community structures remain topics for future work.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149179713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bargaining-based cost sharing shapes the evolution of cooperation in snowdrift games. 基于讨价还价的成本分担决定了雪堆游戏中合作的演变。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0355932

Zijun Li, Haojie Xu, Pengfei Zuo, Yongshuai Wang, Chengyi Xia

{"title":"Bargaining-based cost sharing shapes the evolution of cooperation in snowdrift games.","authors":"Zijun Li, Haojie Xu, Pengfei Zuo, Yongshuai Wang, Chengyi Xia","doi":"10.1063/5.0355932","DOIUrl":"https://doi.org/10.1063/5.0355932","url":null,"abstract":"Cost sharing in the snowdrift game is usually determined only by the strategies of interacting individuals. However, in many collective tasks, the division of cost also depends on whether the participants can reach an acceptable agreement. We, therefore, propose a bargaining-based snowdrift game in which each individual has a bargaining parameter describing the fraction of the cost that the individual would prefer the other participant to bear. In a cooperator-defector interaction, the cost is shared only when their bargaining preferences are compatible; otherwise, the cooperator bears the full cost. We derive a mean-field replicator equation with strategy mutation and examine the model through numerical simulations in well-mixed and networked populations. The results show that cooperation decreases as the cost increases. Distributions concentrated at lower bargaining parameters promote cooperation by increasing the probability of successful cost sharing and reducing the payoff disadvantage of cooperators. Distributions with the same mean can produce different cooperation levels, indicating that the shape of the bargaining-parameter distribution is important. Weak mutation has little effect on the ordering among distributions, whereas strong mutation reduces their differences. Increasing network connectivity generally promotes the cooperation, and the effect of bargaining heterogeneity remains consistent across different network structures. These results show that negotiated cost sharing can influence the evolution of cooperation.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149104831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Second-order consistency for learning chaotic dynamics via randomized Jacobian matching. 随机雅可比匹配学习混沌动力学的二阶一致性。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0347780

Shinhoo Kang, Hai V Nguyen, Tan Bui-Thanh

{"title":"Second-order consistency for learning chaotic dynamics via randomized Jacobian matching.","authors":"Shinhoo Kang, Hai V Nguyen, Tan Bui-Thanh","doi":"10.1063/5.0347780","DOIUrl":"https://doi.org/10.1063/5.0347780","url":null,"abstract":"Short-horizon accuracy does not ensure that a learned chaotic system has correct long-time dynamics. Trajectory (zeroth-order) matching constrains vector-field values, and Jacobian (first-order) matching constrains local tangent dynamics, but neither determines how the Jacobian varies away from supervised states. A model may be locally accurate while drifting toward spurious attractors and distorting long-time statistics. We show that second-order supervision mitigates these failures. Because forming full Hessian tensors is computationally prohibitive in high dimensions, we propose model-constrained randomized Jacobian matching, which compares the Jacobians of the true and learned vector fields at randomly perturbed inputs. A Taylor expansion shows that the expected randomized Jacobian loss decomposes into the Jacobian mismatch plus a Hessian mismatch scaled by the noise variance, implicitly enforcing second-order consistency at O(d2) memory cost without forming the O(d3) Hessian tensor. In Lorenz 63 with minimal temporal supervision, second-order supervision reduces invariant-measure error and Lyapunov-spectrum mean squared error in both paired comparisons and recovers the constant Hessian norm of the true bilinear field. Across five training seeds, explicit Hessian matching produces catastrophic Lyapunov outliers for four of five seeds, whereas randomized Jacobian matching produces none among 5000 on-attractor rollouts. It also has the largest threshold in a directional capture scan, possibly reflecting the neighborhood coverage of its perturbed inputs. In coupled Lorenz 96, first-order methods enter spurious high-amplitude regimes as forcing increases, while second-order methods retain accurate marginals. Randomized Jacobian matching costs about the same as explicit Hessian matching on Lorenz 63 and 40% less on Lorenz 96, with no reference Hessian evaluations during training.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stationary and switching synchronization states in an ensemble of four nonidentical phase oscillators with repulsive couplings. 具有排斥耦合的四个非同相振荡器系综中的稳态和开关同步态。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0315156

A V Bobrova, G V Osipov

{"title":"Stationary and switching synchronization states in an ensemble of four nonidentical phase oscillators with repulsive couplings.","authors":"A V Bobrova, G V Osipov","doi":"10.1063/5.0315156","DOIUrl":"https://doi.org/10.1063/5.0315156","url":null,"abstract":"This study investigates the collective dynamics (phase synchronization, instantaneous frequencies synchronization, and mean frequencies synchronization) in an ensemble of four nonidentical phase oscillators with repulsive coupling. We use the Kuramoto-Sakaguchi system of ordinary differential equations as our mathematical model. Depending on the coupling strength in the presence of a small mismatch of the natural frequencies, all possible states of frequency synchronization were found: 4:0 (global), 3:1, 2:2, and 2:1:1 (cluster). It is shown that these states can be classified into two main types depending on the evolution of the instantaneous frequencies: stationary (4:0 and 2:2), characterized by constancy of phase mismatch and instantaneous frequencies, and switching (3:1 and 2:1:1), in which metastable processes with periodic switching of synchronous states are observed: For different time intervals, different types of locking of instantaneous frequencies of oscillator pairs and different types of phase mismatch were observed. A novel effect of collective dynamics-self-organized emergence of slow-fast behavior in the ensemble of elements which, if decoupled, exhibit uniform temporal evolution-was demonstrated. The rather long time intervals during which the distances between some oscillators stay nearly constant alternate with short epochs of rapid evolution, involving the break up of clusters and their subsequent reassembly. For the 4:0 and 2:2 states, analytical expressions for the synchronization frequencies were derived. The presence of bistability has been revealed depending on the initial conditions of different synchronization states at the same parameters: sets of individual frequencies and value of coupling strength.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149191614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stability analysis of power systems with voltage dynamics based on an invariant probability distribution. 基于不变概率分布的电压动态电力系统稳定性分析。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0333267

Rui Hu, Chunmei Ma, Hai Xiang Lin, Kaihua Xi

{"title":"Stability analysis of power systems with voltage dynamics based on an invariant probability distribution.","authors":"Rui Hu, Chunmei Ma, Hai Xiang Lin, Kaihua Xi","doi":"10.1063/5.0333267","DOIUrl":"https://doi.org/10.1063/5.0333267","url":null,"abstract":"To maintain the transient stability, which is crucial for the proper functioning of power systems, the fluctuations in frequency, voltage, and phase difference need to be within a required secure range. In this study, based on the third-order model of synchronous machines, we model stochastic disturbances by the Brownian motion and use the variance in the invariant probability distribution of a Gaussian process corresponding to the power systems to characterize the state fluctuations. A procedure for calculating these variance matrices is formulated, with which the interplay of the fluctuations between the phase angle dynamics and the voltage dynamics is investigated. It is revealed that increasing line capacity helps improve the phase angle stability but may also lead to more serious voltage fluctuations. Based on the invariant probability distribution, an optimization framework is established to increase the probability of the state staying in the required secure range. Simulations show that the optimization framework can significantly extend the mean first hitting time of the state to the boundary of the required secure set, thus effectively enhancing the transient stability.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149191639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum: "Small sample learning classifies Parkinson's disease patients based on their walking behavior" [Chaos 35, 123125 (2025)]. 勘误：“基于行走行为的小样本学习对帕金森病患者进行分类”[Chaos 35,123125(2025)]。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0359637

Md Mehedi Hasan, Takaaki Hattori, Yoshito Hirata

引用次数: 0

Generative recurrence analysis and metric learning for detection of atrial fibrillation from short ECG data. 基于短心电数据的房颤检测的生成递归分析与度量学习。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0337012

Chunyu Wu, Suwetha Jahan Maheswary, Rakesh Srivastava, Pon Harshavardhanan, Swagat Samantaray, Zimo Wang, Changqing Cheng

{"title":"Generative recurrence analysis and metric learning for detection of atrial fibrillation from short ECG data.","authors":"Chunyu Wu, Suwetha Jahan Maheswary, Rakesh Srivastava, Pon Harshavardhanan, Swagat Samantaray, Zimo Wang, Changqing Cheng","doi":"10.1063/5.0337012","DOIUrl":"https://doi.org/10.1063/5.0337012","url":null,"abstract":"Electrocardiogram (ECG) signals exhibit complex, nonlinear, and nonstationary dynamics that are not fully captured by conventional time series analysis methods. In this study, we propose a novel framework for atrial fibrillation (AF) detection that integrates a beat-level recurrence representation with supervised metric learning. ECG recordings are first segmented into beat-centered waveforms that serve as effective dynamical states, avoiding the inaccurate estimation of time delay and embedding dimension from short recordings. Rather than constructing conventional recurrence plots from delay-embedded trajectories, the proposed method forms a beat-to-beat dissimilarity matrix using the Jensen-Shannon distance between normalized ECG beat segments. This representation captures variations in beat morphology and rhythm irregularity and provides information complementary to heart rate variability descriptors and recurrence quantification features. A contrastive Gaussian-mixture variational autoencoder learns an eight-component latent distribution with two components assigned to each of the four rhythm classes. Reconstruction, Gaussian-mixture regularization, supervised classification, clustering, and contrastive objectives jointly promote informative, compact, and class-discriminative latent representations. Class-conditional samples drawn from the learned mixture provide balanced synthetic latent representations for classifier training. Evaluated on the four-class PhysioNet/CinC 2017 dataset, the proposed framework achieves an overall accuracy of approximately 94%, with F1 scores of 0.97, 0.95, 0.92, and 0.86 for normal sinus rhythm, AF, other rhythm, and noise, respectively. These results demonstrate the potential of combining beat-level nonlinear dynamics, structured generative modeling, and metric learning for AF detection from short ECG recordings.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149104524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergent multifractality in a multi-asset three-state agent-based market model. 基于三状态主体的多资产市场模型中的突现多重分形。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0347841

Rafał Kowalski, Paweł Oświęcimka, Stanisław Drożdż

{"title":"Emergent multifractality in a multi-asset three-state agent-based market model.","authors":"Rafał Kowalski, Paweł Oświęcimka, Stanisław Drożdż","doi":"10.1063/5.0347841","DOIUrl":"https://doi.org/10.1063/5.0347841","url":null,"abstract":"This work introduces an Ising-inspired, multi-asset, three-state agent-based model designed to explain how multifractality and long-range nonlinear dependencies emerge in financial markets. Agents can take one of three states-buy, sell, or remain inactive-and their decisions depend on local neighbor interactions, global market sentiment, and cross-asset coupling between multiple financial instruments. The model reproduces key empirical market features, such as volatility clustering, heavy-tailed return distributions, long memory in volatility, and broad multifractal spectra, showing that these properties arise naturally from collective agent behavior rather than being imposed externally. A central result is that strong multifractality appears near a critical balance between individual autonomy and collective synchronization. When agents are too independent, the system is nearly monofractal; when they are too strongly coupled, the market \"freezes\" into overly stable states. The richest hierarchical structure emerges near the transition between these regimes, where the system alternates between metastable phases and turbulent rearrangements. Extending the model to multiple assets also generates realistic multiscale cross correlations between returns, suggesting that financial correlations arise mainly from direct interactions among investors and only secondarily from asset prices themselves. Overall, the study provides a mechanistic explanation for how complex multiscale organization in financial markets can emerge from simple microscopic interaction rules. From the perspective of applied soft computing, the proposed framework provides an interpretable and flexible computational intelligence approach for modeling complex adaptive financial systems, offering both predictive insight and a deeper understanding of emergent market behavior.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"36 10","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149179658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergence of cooperation in reactive strategy space through similarity-based interactions. 通过基于相似性的互动，反应策略空间中合作的出现。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0356075

Jiancheng Zhao, Jing Zhang, Zhihai Rong, Xiuli Du, Wen Yang

引用次数: 0

Hidden synchrony in networks through Laplacian-spectrum-based En matrices. 基于拉普拉斯谱的En矩阵的网络隐同步。

IF 3.3 2区数学

Chaos Pub Date : 2026-10-01 DOI: 10.1063/5.0350660

Sajad Jafari, Deivasundari Muthukumar, Karthikeyan Rajagopal, Atiyeh Bayani, Fahimeh Nazarimehr

引用次数: 0

Chaos最新文献