Detection of synchronised chaos in coupled map networks using symbolic dynamics

We present a method based on symbolic dynamics for the detection of synchronization in networks of coupled maps and distinguishing between chaotic and random iterations. The symbolic dynamics are defined using special partitions of the phase space which prevent the occurrence of certain symbol sequences related to the characteristics of the dynamics. Synchrony in a large network can be detected using measurements from only a single node by checking for the presence of forbidden symbol transitions. The method utilises a relatively short time series of measurements and hence is computationally very fast. Furthermore, it is robust against parameter uncertainties, is independent of the network size, and does not require knowledge of the connection structure.