Thermodynamics of complex systems

Abstract

The departure from equilibrium as the source of complex behaviour establishes a natural link between the thermodynamics of irreversible processes, on the one hand, and nonlinear dynamic systems, stochastic processes, and the theory of fluctuations, on the other. What thermodynamics can contribute to the understanding of nonlinear behavior arising past the instability threshold of nonequilibrium is instructive to investigate twenty years after this important discovery was made. In this paper, the idea is developed that, in order to meet this challenge, the scope of thermodynamics must be extended by incorporating the concepts and the techniques of nonlinear dynamics and the theory of stochastic processes. Recent results of generalized thermodynamics are presented herein, in particular in connection with the problem of selection of states and the information entropy for a bifurcation.