THE THEORY OF THE
QUANTUM
WORLD
Proceedings of the 25th Solvay Conference on Physics
THE THEORY OF THE
QUANTUM
WORLD
Brussels, Belgium 1922 October 2011
Editors
David Gross
Director, Kavli Institute for Theoretical Physics
University of California, Santa Barbara, USA
Marc Henneaux
Universit Libre de Bruxelles
Director, International Solvay Institutes, Belgium
Alexander Sevrin
Vrije Universiteit Brussel
Also at the Universiteit Antwerpen and the KULeuven
Deputydirector, International Solvay Institutes, Belgium
World Scientific
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THE THEORY OF THE QUANTUM WORLD
Proceedings of the 25th Solvay Conference on Physics
Copyright 2013 by World Scientific Publishing Co. Pte. Ltd.
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ISBN 9789814440639
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The International Solvay Institutes
Board of Directors
Members
Mr. Jean-Marie Solvay
President
Prof. Franz Bingen
Vice-President and Emeritus-Professor at the VUB
Prof. Lode Wyns
Secretary and Vice-Rector for Research at the VUB
Mr. Philippe Busquin
Minister of State and Former European Commissioner
Prof. Eric De Keuleneer
Solvay Brussels School of Economics & Management
Mr. Bernard de Laguiche
Chief Financial Officer of Solvay S.A.
Mr. Alain Delchambre
President of the Administrative Board of the ULB
Baron Daniel Janssen
Honorary Chairman of the Board of Directors of Solvay S.A.
Mr. Eddy Van Gelder
President of the Administrative Board of the VUB
Honorary Members
Baron Andr Jaumotte
Honorary Director of the Solvay Institutes, Honorary Rector,
Honorary President of the ULB
Mr. Jean-Marie Piret
Emeritus Attorney General of the Supreme Court of Appeal
and Honorary Principal Private Secretary to the King
Prof. Jean-Louis Vanherweghem
Former President of the Administrative Board of the ULB
Prof. Irina Veretennicoff
Emeritus Professor at the VUB
Guest Members
Prof. Marc Henneaux
Director and Professor at the ULB
Prof. Alexander Sevrin
Deputy Director, Professor at the VUB and Scientific Secretary of the
Committee for Physics
Prof. Franklin Lambert
Emeritus Professor at the VUB
Prof. Anne De Wit
Professor at the ULB and Scientific Secretary of the Committee for Chemistry
Prof. Herv Hasquin
Permanent Secretary of the Royal Academy of Sciences, Letters and Fine Arts
of Belgium
Prof. Gry van Outryve dYdewalle
Permanent Secretary of the Royal Flemish Academy of Belgium for Sciences
and the Arts
Director
Prof. Marc Henneaux
Professor at the ULB
Solvay Scientific Committee for Physics
Prof. David Gross (Chair)
Kavli Institute for Theoretical Physics (Santa Barbara, USA)
Prof. Roger Blandford
Stanford University (USA)
Prof. Steven Chu
Stanford University (USA)
Prof. Robbert Dijkgraaf
Universiteit van Amsterdam (The Netherlands)
Prof. Bert Halperin
Harvard University (Cambridge, USA)
Prof. Giorgio Parisi
Universit`a la Sapienza (Roma, Italy)
Prof. Pierre Ramond
University of Florida (Gainesville, USA)
Prof. Gerard t Hooft
Spinoza Instituut (Utrecht, The Netherlands)
Prof. Klaus von Klitzing
Max-Planek-Institut (Stuttgart, Germany)
Prof. Peter Zoller
Universitt Innsbruck (Austria)
Prof. Alexander Sevrin (Scientific Secretary)
Vrije Universiteit Brussel (Belgium)
In Memoriam Jacques Solvay (1920-2010)
It is with great sadness that the Board of Directors of the International SolvayInstitutes for Physics and Chemistry, founded by Ernest Solvay, learned of thepassing away of its President, Jacques Solvay on April 29, 2010.
Throughout his life, Jacques Solvay demonstrated a keen interest for scientificresearch and supported and encouraged the development of science at the highestlevel.
Jacques Solvay was the inaugural President of the Board of Directors of theInternational Solvay Institutes upon their creation in 1970. From as early as thefifties, he expressed his strong intention to continue the work initiated by his greatgrandfather,Ernest Solvay, by becoming an active member of the administrativecommittees of the Institute for Physics and the Institute for Chemistry prior totheir merger.
Under his direction and that of Ilya Prigogine with whom he shared a commonpurpose the Institutes broadened their activities and developed new research directions.At the same time, Jacques Solvay maintained a strong focus on the SolvayConferences for Physics and Chemistry, an activity which he kept close to his heart.The hospitality which Mr. and Mrs. Solvay extended to the participants contributedgreatly to the prestige and the success of these events.
With the passing of Jacques Solvay, the international scientific community losesa great friend of science. The Institutes will keep a vivid and grateful memoryof Jacques Solvay and offer their condolences to his widow and the whole SolvayFamily.
To honor the memory of Jacques Solvay, the Board of Directors created theInternational Jacques Solvay Chair for Physics. The Board of Directors expressestheir gratitude to the Solvay Family which supported this initiative.
Hotel Mtropole (Brussels), 19-22 October 2011
The Theory of the Quantum World
Chair: Professor David Gross
The 25th Solvay Conference on Physics took place in Brussels from October19 through October 22, 2011 celebrating one century of tradition and scientificexcellence initiated by Lorentz at the 1st Solvay Conference on Physics in 1911(Premier Conseil de Physique Solvay). The conference was preceded by an AcademicSession Why Curiosity Driven Science? in the presence of His Royal Highness KingAlbert II of Belgium. The conference was followed by a public event entitled TheFuture of Physics. William Phillips and Frank Wilczek each delivered a lecture anda panel of scientists led by David Gross and consisting of Alain Aspect, Gerard tHooft, William Phillips, Subir Sachdev, Frank Wilczek and Peter Zoller answeredquestions from the audience.
The organization of the 25th Solvay Conference has been made possible thanksto the generous support of the Solvay Family, the Solvay Company, the UniversitLibre de Bruxelles, the Vrije Universiteit Brussel, the Belgian National Lottery, theFoundation David and Alice Van Buuren, the Belgian Science Policy Office, theCommunaut francaise de Belgique, de Actieplan Wetenschapscommunicatie of theVlaamse Regering, the City of Brussels, the Max-Planck-Gesellschaft and the HtelMtropole.