  We extend the concept of generalized synchronization of chaos, a phenomenon
that occurs in driven dynamical systems, to the context of autonomous
spatiotemporal systems. It means a situation where the chaotic state variables
in an autonomous system can be synchronized to each other but not to a coupling
function defined from them. The form of the coupling function is not crucial;
it may not depend on all the state variables nor it needs to be active for all
times for achieving generalized synchronization. The procedure is based on the
analogy between a response map subject to an external drive acting with a
probability p and an autonomous system of coupled maps where a global
interaction between the maps takes place with this same probability. It is
shown that, under some circumstances, the conditions for stability of
generalized synchronized states are equivalent in both types of systems. Our
results reveal the existence of similar minimal conditions for the emergence of
generalized synchronization of chaos in driven and in autonomous spatiotemporal
systems.
