讲座题目：The transition to synchronization of networked dynamical systems
主讲人：Stefano Boccaletti 教授
主持人：周杰 副教授
开始时间：2024-11-04 9:30
讲座地址：闵行校区物理楼226报告厅
主办单位：物理与电子科学学院
报告人简介：
Italian CNR, in Florence. His major scientific interests are i) pattern formation and competition in extended media, ii) control and synchronization of chaos, and iii) the structure and dynamics of complex networks. He is Editor in Chief of the Journal “Chaos, Solitons and Fractals” (Elsevier) from 2013, and member of the Academia Europaea since 2016. He was elected member of the Florence City Council from 1995 to 1999. Boccaletti has published 352 papers in peer-reviewed international Journals, which received more than 35,000 citations (Google Scholar). His h factor is 70 and his i-10 index is 227. With more than 12,300 citations, the monograph “Complex Networks: Structure and Dynamics”, published by Boccaletti in Physics Reports on 2006 converted into the most quoted paper ever appeared in the Annals of that Journal.
报告内容：
From brain dynamics and neuronal firing, to power grids or financial markets, synchronization of networked unitsis the collective behavior characterizing the normal functioning of most natural and man made systems.As a control parameter (typically the coupling strength in each link of the network) increases, a transition occursbetween a fully disordered and gaseous-like phase (where the units evolve in a totally incoherent manner) to an ordered or solid-like phase (in which, instead, all units follow the same trajectory in time).The transition between such two phases can be discontinuous and irreversible, or smooth, continuous, and reversible.The first case is known as Explosive Synchronization, and refers to an abrupt onset of synchronization followingan infinitesimally small change in the control parameter. The second case is the most commonly observed one, and corresponds to a second-order phase transition, resulting in intermediate states emerging in between the two phases. Namely, the path to synchrony is here characterized by a sequence of events where structured states emerge made of different functional modules (or clusters), each one evolving in unison. In my talk, I will assume that, during the transition, the synchronous solution of each cluster does not differ substantially from thatof the entire network and, under such an approximation, I will introduce a (simple, effective, and limited in computational demand) method which is able to: i) predict the entire sequence of events that are taking place during the transition, ii) identify exactly which graph's node is belonging to each of the emergent clusters, and iii) provide a well approximated calculation of the critical coupling strength value at which each of such clusters is observed to synchronize, iv) use the cluster properties to suitably control and tame cluster synchronization. I will also demonstrate that, under the assumed approximation, the sequence of events is in fact universal, in that it is independent of the specific dynamical system operating in each network's node and depends, instead, only on the graph's structure.
