Decoherence and the Quantum Theory of the Classical
Starts 16 May 2017 16:30
Ends 16 May 2017 18:00
Central European Time
ICTP, Trieste, Italy
Leonardo Building - Budinich Lecture Hall
Strada Costiera 11
34151 Trieste, Italy
Wojciech Hubert Zurek is a leading authority on quantum theory, especially decoherence and non-equilibrium dynamics of symmetry breaking and resulting defect generation (known as the Kibble-Zurek mechanism). He was educated in Kraków, Poland and Austin, Texas (Ph.D. 1979). He spent two years at Caltech as a Tolman Fellow. In 1984 he started at Los Alamos as Oppenheimer Fellow, and was elected Laboratory Fellow in 1996. He was an External Professor at the Santa Fe Institute and co-organized the Quantum Coherence and Decoherence and the Quantum Computing and Chaos programs at UCSB's Institute for Theoretical Physics. In 2005 he received the Alexander von Humboldt Prize, in 2009 Marian Smoluchowski Medal (highest prize of the Polish Physical Society), and in 2010 Albert Einstein Professorship Prize of the Ulm University. Among the books are Quantum theory and Measurement (1983, co-edited with John Wheeler) and Complexity, Entropy, and Physics of Information (1990).
Abstract: I will describe three insights into the transition from quantum to classical. After a brief discussion of decoherence I will give (i) a minimalist (and decoherence-free) derivation of preferred states. Such pointer states define events (e.g., measurement outcomes) without appealing to Born's rule . Probabilities and (ii) Born’s rule can be then derived from the symmetries of entangled quantum states. With probabilities at hand one can analyze information flows from the system to the environment in course of decoherence. They explain how (iii) robust “classical reality” arises from the quantum substrate by accounting for all the symptoms of objective existence of preferred pointer states of quantum systems through the redundancy of their records in the environment. Taken together, and in the right order, these three advances (i)-(iii) elucidate quantum origins of the classical.