Collective Chaos in a Population of Globally Coupled Oscillators

Different forms of collective chaos are found in a large population of globally coupled identical oscillators of the complex Ginzburg-Landau type. Under certain conditions, the entire population splits into three point-clusters, and their coupled dynamics generates chaos of low dimension. It also occurs that all these clusters are fused into one continuous distribution in the form of a closed loop. This object exhibits stretching-and-folding behavior charcteristic to chaos, whose interpretation is provided from the approximate equivalence of our system to an ensemble of independent oscillators driven by a common periodic field. It is found that collective chaos also arises when fused and point clusters coexist.