Several complex systems can be modeled as large networks in which the state of the nodes continuously evolves through interactions among neighboring nodes, forming a high-dimensional nonlinear dynamical system. One of the main challenges of Network Science consists in predicting the impact of network topology and dynamics on the evolution of the states and, especially, on the emergence of collective phenomena, such as synchronization. We address this problem by proposing a Dynamics Approximate Reduction Technique (DART) that maps high-dimensional (complete) dynamics unto low-dimensional (reduced) dynamics while preserving the most salient features, both topological and dynamical, of the original system. DART generalizes recent approaches for dimension reduction by allowing the treatment of complex-valued dynamical variables, heterogeneities in the intrinsic properties of the nodes as well as modular networks with strongly interacting communities. Most importantly, we identify three major reduction procedures whose relative accuracy depends on whether the evolution of the states is mainly determined by the intrinsic dynamics, the degree sequence, or the adjacency matrix. We use phase synchronization of oscillator networks as a benchmark for our threefold method. We successfully predict the synchronization curves for three phase dynamics (Winfree, Kuramoto, theta) on the stochastic block model. Moreover, we obtain the bifurcations of the Kuramoto-Sakaguchi model on the mean stochastic block model with asymmetric blocks and we show numerically the existence of periphery chimera state on the two-star graph. This allows us to highlight the critical role played by the asymmetry of community sizes on the existence of chimera states. Finally, we systematically recover well-known analytical results on explosive synchronization by using DART for the Kuramoto-Sakaguchi model on the star graph.
Optimal synchronization of Kuramoto oscillators: a dimensional reduction approach
最近提出的降维方法研究同步在仓本模型中建立最佳的网络拓扑结构,以促进或抑制同步。该方法的基础是在一个集体坐标的锁相振荡器的时间演化的介绍,在的精神,安东森anquiry。我们证明了仓本网络的最优同步要求二次函数$ω^T L ω$的最大化,其中$ω$代表振荡器的固有频率的向量,和$L$网络的拉普拉斯矩阵。许多最近得到的数值结果可以重新获得解析和更简单的方式从我们的最大化条件。提出了一种计算效率高的{爬山}重布线算法来生成具有最佳同步特性的网络。我们的方法可以很容易地适应的情况下,仓本模型的吸引力和排斥力的相互作用,并再次许多最近的数值结果可以重新推导在一个更简单,更清晰的分析方式。
Vrije Universiteit Amsterdam(阿姆斯特丹自由大学);Universität Hamburg(汉堡大学);Saint Louis University(圣路易斯大学);University of Oxford(牛津大学);University of Exeter(埃克塞特大学);Technische Universität München(慕尼黑工业大学)
Synchronization of Dirac-Bianconi driven oscillators
RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS)(理化学研究所交叉理论与数学科学中心(iTHEMS));Department of Systems and Control Engineering, Institute of Science Tokyo (former Tokyo Tech)(东京科学大学系统控制工程系(原东京工业大学));Department of Applied Mathematics and Computer Science, Universidad de Cantabria(坎塔布里亚大学应用数学与计算机科学系);Department of Complex and Intelligent Systems, Future University Hakodate(函馆未来大学复杂智能系统系);International Research Frontiers Initiative, Institute of Science Tokyo (former Tokyo Tech)(东京科学大学国际研究前沿倡议项目(原东京工业大学))