# Bell's theorem, entanglement, quantum teleportation and all that

Prof. Anthony J. Leggett (University of Illinois at Urbana-champaign, USA)

16.04.2007 at 17:15

## About:

One of the most surprising aspects of quantum mechanics is that under certain circumstances it does not allow individual physical systems, even when isolated, to possess properties in their own right. This feature, first clearly appreciated by John Bell in 1964, has in the last three decades been tested experimentally and found (in most people's opinion) to be spectacularly confirmed. More recently it has been realized that it permits various operations which are classically impossible, such as "teleportation" and secure-in- principle cryptography. This talk is a very basic introduction to the subject, which requires only elementary quantum mechanics.

## Short Biography

Professor Anthony J. Leggett, a faculty member of the University of Illinois at Urbana-Champaign since 1983, is widely recognized as a world leader in the theory of low-temperature physics. He was awarded the Nobel Prize in Physics in 2003 (jointly with Alexei A. Abrikosov and Vitaly L. Ginzburg) for his pioneering work on superfluidity.

Anthony Leggett has shaped the theoretical understanding of normal and superfluid helium liquids and other strongly coupled superfluids. He set directions for research in the quantum physics of macroscopic dissipative systems and use of condensed systems to test the foundations of quantum mechanics. His research interests lie mainly within the fields of theoretical condensed matter physics and the foundations of quantum mechanics. He has been particularly interested in the possibility of using special condensed-matter systems, such as Josephson devices, to test the validity of the extrapolation of the quantum formalism to the macroscopic level; this interest has led to a considerable amount of technical work on the application of quantum mechanics to collective variables and in particular on ways of incorporating dissipation into the calculations. He is also interested in the theory of superfluid liquid 3He, especially under extreme nonequilibrium conditions, in high-temperature superconductivity, and in the newly realized system of Bose-condensed atomic gases.

Audimax - LMU - Geschwister-Scholl-Platz 1 - 80333 Muenchen