On the positivity condition in the nonunitary transformation theory of irreversibility
Abstract
The Misra–Prigogine–Courbage Nonunitary Transformation Theory of Irreversibility is revisited in connection with the role played by the fundamental positivity preserving condition of the associated semigroup evolution. Comparisons between various viewpoints referring to general context of non-Markovian formulations are given. Some recent criticism of the Misra–Prigogine–Courbage theory regarding attempts to derive irreversibility and the approach to equilibrium without any approximations and/or loss of information is corrected. © 1993 John Wiley & Sons, Inc.