Symmetry-breaking mechanism for the formation of robust and stable chimera patterns.

Synchronization of the dynamics of the individual entities that constitute complex systems has been observed and systematically studied for more than four decades now. An exotic behavior that has triggered scientists' curiosity for a long time is the emergence of chimera states, long-lasting dynamical patterns of coexistence of synchronous and asynchronous clusters of nodes in networked systems. Although many features have been understood so far, many questions remain unanswered. In particular, the stability of such states for finite networks of oscillators and their high sensitivity to the initial conditions have not yet been tackled exhaustively. Here we show that the formation of clustered synchronization can follow a global symmetry-breaking mechanism, which is also responsible for selecting the nature of the final patterns. Through this novel method, we show that it is possible to reconcile the pattern formation process with cluster synchronization, paving the way to a robust mechanism for explaining the formation of stable chimera states in networks of coupled dynamical systems.