Markovian Behaviour and Constrained Maximization of the Entropy in   Chaotic Quantum Systems
  The separation of the Schr\"{o}dinger equation into a Markovian and an interference term provides a new insight in the quantum dynamics of classically chaotic systems. The competition between these two terms determines the localized or diffusive character of the dynamics. In the case of the Kicked Rotor, we show how the constrained maximization of the entropy implies exponential localization. 
A. Romanelli, A.C. Sicardi Schifino, G. Abal, R. Siri and R. Donangelo