Informational-statistical thermodynamics of a complex system

We apply a statistical-thermodynamic approach to the study of a particular physical system (two sets of nonlinearly coupled oscillators), driven far a way from equilibrium. Such a system displays a kind of complex behavior con sisting in the so-called Frohlich effect leading in steady-state conditions to a nonequilibrium phase condensation resembling the Bose-Einstein conden sation of systems in equilibrium. A kind of "two-fluid model" arises: the " normal nonequilibrium phase" and Frohlich condensate or "nonequilibrium sup erphase," which is shown to be an attractor of the system. We work out some aspects of the irreversible thermodynamics of this dissipative complex sys tem. Particular nonlinear properties are discussed and Lyapunov exponents d etermined. This kind of system gives a good modeling of polar vibration mod es in polymers and biopolymers. (C) 2000 American Institute of Physics. [S0 021-9606(00)50808-3].