Modern Studies of Basic Quantum Concepts and Phenomena (NS 104)

June 14-17, 1997
Gimo Herrgård, Gimo, Sweden
Organizers: Professor Erik B. Karlsson (Chairman), Associate Professor Erkki Brändas, Professor Osvaldo Goscinski and Professor Carl Nordling, Uppsala University; Professor Bengt Nagel and Associate Professor Göran Lindblad, Royal Institute of Technology, Stockholm; and Professor Gösta Ekspong, Stockholm University.

Although quantum mechanics existed for more than 70 years, its inner structure and applicability are still being discussed. The fathers of quantum mechanics presented "Gedanken experiments" that have only been possible to carry out over the past 10-15 years, thanks to various technological developments. These experiments have answered many questions but have also led to new ones requiring further and more detailed studies of fundamental quantum phenomena, such as locality and reversibility. Symposium participants explained the refined measuring methods that led to this knowledge, as well as the resulting conclusions about the nature of light and matter (knowledge that, in many cases, may be used for technical applications in the near future).

Interferometric methods can be applied nowadays not only to photons, but also to particle waves (electrons, neutrons and atoms as a whole). Individual atoms can be captured and controlled in traps or cavities and be made to couple quantum mechanically to each other via photon or phonon fields. Electronic circuits can be built so small that they approach atomic dimensions. Wave function coherence plays a crucial role in theoretical descriptions of these "new" systems, and much of the symposium was devoted to the conditions governing quantum mechanical coherence and its preservation.

The conditions that govern coherence also play a vital role in existing proposals for "quantum computers," which were discussed at the symposium both in terms of technical design and their information theory aspects. Other interesting aspects are the potential this offers in cryptogarphy, as well as the sensational concept of "teleportation."

The natural limitations of measuring technology have always been a key point in quantum mechanics. Here too, major progress has recently been achieved, under certain circumstances enabling researchers to improve the accuracy of measurements of a certain magnitude (at the expense of accuracy in another). This will be important, for example, in recording gravitational waves from cosmic explosions.

The participants agreed that today this field is in a highly interesting phase of development and that the timing of the symposium was very well chosen in light of future work. Symposium contributions have been published in the journal Physica Scripta and as a separate volume in cooperation with World Scientific, Singapore.

Participants
Yakir Aharonov Tel Aviv University, Israel	Adrian Kent University of Cambridge UK
Mauritz Andersson Institutionen för Kvantkemi Uppsala, Sweden	Jeff Kimble Caltech, USA
Alain Aspect Institut d'Optique, France	Peter L. Knight Imperial College London, UK
Anders Bárány Stockholm University Stockholm, Sweden	Paul G. Kwiat Los Alamos National Lab., USA
Ingemar Bengtsson Stockholm Universty, Stockholm, Sweden	Rolf Landauer IBM Thomas J. Watson Research Center, USA
Charles H. Bennett IBM Research Division, USA	Anthony Leggett University of Illinois USA
Gunnar Björk KTH, Stockholm, Sweden	Jon Magne Leinaas Fysisk Institut, Oslo, Norway
Vladimir Braginsky Moscow State University, Russia	Göran Lindblad KTH, Stockholm, Sweden
Erkki Brändas Institutionen för Kvantkemi Uppsala, Sweden	Leonard Mandel University of Rochester USA
Henrik Carlsen Institutionen för Kvantkemi Uppsala, Sweden	Jürgen Mlynek Universität Konstanz Germany
Raymond Chiao University of California, Berkeley, Calif., USA	Bengt Nagel Fysiska Insitutionen Uppsala, Sweden
Tord Claeson Fysiska Inst., CTH Göteborg, Sweden	Carl Nordling Fysiska Insitutionen Uppsala, Sweden
Claude Cohen-Tannoudji Ecole Normale Supérieure France	Asher Peres Technion, Israel
Michel Devoret CEA, Saclay, France	Helmut Rauch Atominstitut der Österreichischen Unversitäten, Austria
C. A. Driesmann Techniscke Universität Berlin, Germany	Wolfgang Schleich Univesität Ulm, Germany
Artur K. Ekert Oxford University, UK	Marlan O. Scully Texas A & M University USA
Gösta Ekspong Stockholm University, Stockholm, Sweden	Bo-Sture Skargerstam Norwegian University of Science and Technology Trondheim, Norway
Edward Fry Texas A & M University, USA	Stig Stenholm Fysiska Institutionen Uppsala, Sweden
Daniel M. Greenberger CCNY, New York, USA	Sune Svanberg Lunds Tekniska Högskola Lund, Sweden
Osvaldo Goscinski Institutionen för Kvantkemi Uppsala, Sweden	Hideaki Takanayagi NTT Basic Research Laboratories, Japan
Serge Haroche Ecole Normale Supérieure France	Akira Tonomura Advanced Research Laboratory, Hitachi Ltd. Japan
James B. Hartle USCB, Santa Barbara, USA	Herbert Walther Max-Planck-Institut für Quantenoptik, Germany
Björn Hessmo Institutionen för Kvantkemi Uppsala, Sweden	David Wineland NIST, USA
Yoseph Imry Weizmann Institute for Science, Israel	Yoshihisa Yamamoto Stanford University USA
Cecilia Jarlskog LTH, Lund, Sweden	Anton Zeilenger Innsbruck University Austria
Mats Jonson CTH, Göteborg, Sweden	Peter Zoller Universität Innsbruck Austria
Erik B. Karlsson Fysiska Institutionen Uppsala, Sweden	Wojciech Zurek Los Alamos National Laboratory, USA
Anders Karlsson KTH-Elektrum Kista, Sweden