  A novel regime of synchronization, called remote synchronization, where the
peripheral nodes form a phase synchronized cluster not including the hub, was
recently observed in star motifs. We show the existence of a more general
dynamical state of remote synchronization in arbitrary networks of coupled
oscillators. This state is characterized by the synchronization of pairs of
nodes that are not directly connected via a physical link or any sequence of
synchronized nodes. This phenomenon is almost negligible in networks of phase
oscillators as its underlying mechanism is the modulation of the amplitude of
those intermediary nodes between the remotely synchronized units. Our findings
thus show the ubiquity and robustness of these states and bridge the gap from
their recent observation in simple toy graphs to complex networks.
