DECOHERENCE, CHAOS, THE QUANTUM AND THE CLASSICAL

The key ideas of the environment-induced decoherence approach are revi ewed. Application of decoherence to the transition from quantum to cla ssical in open quantum systems with chaotic classical analogs is descr ibed. The arrow of time is, in this context, a result of the informati on loss to the correlations with the environment. The asymptotic rate of entropy production (which is reached quickly, on the dynamical time scale) is independent of the details of the coupling of the quantum s ystem to the environment, and is set by the Lyapunov exponents. We als o briefly outline the existential interpretation of quantum mechanics, justifying the slogan <<No information without representation>>.