Wojciech H. Zurek
Wojciech Hubert Zurek (born 1951) is a theoretical physicist and a leading authority on quantum theory, especially decoherence and non-equilibrium dynamics of symmetry breaking and resulting defect generation (known as Kibble-Zurek mechanism). He is a staff scientist at Los Alamos National Laboratory and also a Laboratory Fellow (a prestigious distinction for a US National Laboratory scientist). Zurek was awarded the Albert Einstein Professorship Prize by the Foundation of the University of Ulm in Germany in 2010.
Zurek pioneered (with Tom W. B. Kibble) a paradigmatic framework for understanding defect generation in non-equilibrium processes, particularly, for understanding topological defects generated when a second-order phase transition point is crossed at a finite rate. The paradigm covers phenomena of enormous varieties and scales, ranging from structure formation in early Universe to vortex generation in superfluids. The key mechanism of critical defect generation is known as Kibble-Zurek mechanism, and the resulting scaling laws as the Kibble-Zurek scaling laws.
He pointed out the fundamental role of environment in determining a set of special basis states immune to environmental decoherence (pointer basis) which defines a classical measuring apparatus unambiguously. His work on decoherence paves a way towards the understanding of emergence of the classical world from the quantum mechanical one, getting rid of ad hoc demarcations between the two, like the one imposed by Niels Bohr in the famous Copenhagen interpretation of Quantum Mechanics. The underlying mechanism proposed and developed by Zurek and his collaborators is known as Quantum Darwinism. His work also has a lot of potential benefit to the emerging field of quantum computing.
Zurek earned his M.Sc. in Kraków, Poland in 1974 and completed his Ph.D. under advisor William C. Schieve at the University of Texas at Austin in 1979. He spent two years at Caltech as a Tolman Fellow, and started at LANL as a J. Oppenheimer Fellow. He was the leader of the Theoretical Astrophysics Group at Los Alamos from 1991 until he was made a Laboratory Fellow in the Theory Division in 1996. Zurek is currently a foreign associate of the Cosmology Program of the Canadian Institute for Advanced Research. He served as a member of the external faculty of the Santa Fe Institute, and has been a visiting professor at the University of California, Santa Barbara. Zurek co-organized the Quantum Coherence and Decoherence as well as the Quantum Computing and Chaos Programs at UCSB's Institute for Theoretical Physics.
He researches decoherence, physics of quantum and classical information, non-equilibrium dynamics of defect generation, foundations of statistical and of quantum physics, and astrophysics. He is also the co-author, along with William Wootters and Dennis Dieks, of a proof stating that a single quantum cannot be cloned (see the no cloning theorem). He also coined the terms einselection and quantum discord. He is a pioneer in information physics, edited an influential book on "Complexity, Entropy and the Physics of Information", and spearheaded the efforts that finally exorcised Maxwell's demon. Zurek showed that the demon can extract energy from its environment for "free" as long as it (a) is able to find structure in the environment, and (b) is able to compress this pattern (whereas the remaining code is more succinct than the brute-force description of the structure). Like this the demon can exploit thermal fluctuations. However, he showed that in thermodynamic equilibrium (the most likely state of the environment), the demon can at best break even, even if the information about the environment is compressed. As a result of his exploration, Zurek suggests to redefine entropy and distinguish between two parts: the part that we already know about the environment (measured in Kolmogorov complexity, and, conditioned on our knowledge, the remaining uncertainty (measured in Shannon entropy).