An extension of classical thermodynamics to non-linear systems and far-from-equilibrium situations in which self-organization may occur. It shows how new forms of order may emerge via state transitions when energy flows exceed the dissipating capacity of an existing structure. The process by which this is achieved is irreversible (i.e., once a new structure emerges, the system cannot return to its initial reference state). Non-linear systems are referred to as dissipative systems in irreversible thermodynamics. Both classical and irreversible thermodynamics have had an impact on the theoretical development of dynamical systems approaches to behaviour and development.
See Bifurcation, Catastrophe theory, Chaos theory, Classical thermodynamics, Dissipative systems, Dynamical systems approaches, First law of thermodynamics, General system theory (GST), Non-linear dynamics, Second law of thermodynamics, Self-organization, Synergetics