  We discuss the structure and main features of the nonlinear evolution
equation proposed by this author as the fundamental dynamical law within the
framework of Quantum Thermodynamics. The nonlinear equation generates a
dynamical group providing a unique deterministic description of irreversible,
conservative relaxation towards equilibrium from any non-equilibrium state, and
satisfies a very restrictive stability requirement equivalent to
Hatsopoulos-Keenan statement of the second law of thermodynamics. Here, we
emphasize its mathematical structure and its applicability also within other
contexts, such as Classical and Quantum Statistical Mechanics, and Information
Theory.
