An attempted model for dynamic centrality in complex networks

Scott A. Hill, Physics, University of Dallas

A recent paper (Braha and Bar-Yam, Complexity 12(2):1-5 2006) discovered the phenomenon of dynamic centrality in a scale-free email network, where the network was scale-free even on a daily basis, but with hubs that shifted from day to day. This raises two questions: (1) why should the aggregate of a set of scale-free networks also be scale-free, and (2) why should the daily networks be scale-free at all, since they form over a timespan presumably too short for certain nodes to become "popular" as in the rich-get-richer model. This talk will address these questions, by presenting a possible theoretical model for dynamic centrality.