These proceedings comprise the plenary lectures and poster contributions of the 'Heinz von Foerster Conference 2011' on Emergent Quantum Mechanics (EmerQuM11), which was held at the University of Vienna, 11?13 November 2011. With the 5th International Heinz von Foerster Conference convened at the occasion of von Foerster's 100th birthday, the organizers opted for a twin conference to take place at the Large and Small Ceremonial Halls of the University's main building, respectively. The overall topic was chosen as 'Self-Organization and Emergence', a topic to which von Foerster was an early contributor. While the first conference ('Self-Organization and Emergence in Nature and Society') addressed a more general audience, the second one ('Emergent Quantum Mechanics') was intended as a specialist meeting with a contemporary topic that could both serve as an illustration of von Foerster's intellectual heritage and, more generally, point towards future directions in physics. We thus intended to bring together many of those physicists who are interested in or are working on attempts to understand quantum mechanics as emerging from a suitable classical (or, more generally, deeper level) physics. EmerQuM11 was organized by the Austrian Institute for Nonlinear Studies (AINS), with essential support from the Wiener Institute for Social Science Documentation and Methodology (WISDOM), the Department of Contemporary History at the University of Vienna, and the Heinz von Foerster-Gesellschaft. There were a number of individuals who contributed to the smooth course of our meeting and whom I would like to sincerely thank: Christian Bischof, Thomas Elze, Marianne Ertl, Gertrud Hafner, Werner Korn, Angelika Krawanja, Florian Krug and his team, Sonja Lang, Albert M?ller, Ilse M?ller, Irene M?ller, Karl M?ller, Armin Reautschnig, Marion Schirrmacher, Anton Staudinger, Roman Zlabinger, and, last but not least, my AINS colleagues Siegfried Fussy, Herbert Schwabl and Johannes Mesa Pascasio, the latter in particular for his invaluable technical help with these proceedings. Funds made available by the Federal Ministry of Science and Research (BMWF), the City of Vienna MA7 Science Funding, the Faculty of Historical and Cultural Studies, Blaha Office Furniture, and Padma AG Zurich are gratefully acknowledged. As for the nature of the search for a 'deeper level' foundation of quantum mechanics, a first difficulty already arises with respect to the question: Where do we start? One may look for quite different points of departure, such as an encompassing theory of quantum gravity. Or one may find arguments for the necessity to base one's approach at least on a relativistic formulation of the problem. Or one may discard searching for general principles for the time being, and develop an explicit physical model first. And so on. In fact, this is actually what is happening today in different research programs for emergent quantum mechanics, a fact which is also reflected in the rich variety of approaches presented at our meeting. This may be considered a very welcome situation, reminding us of Heinz von Foerster's dictum: 'Act always so as to increase the number of choices.' However, some may view this variety also as a drawback: There is not (yet?) a single, definite alternative theory that would challenge orthodox positions, for example, by providing different experimental predictions. However, the prevailing orthodoxy has shown throughout the 20th century to the present day, that a too restrictive attitude towards theoretical alternatives can lead to almost a standstill in coping with the serious shortcomings and contradictions of present-day physics. Many of us remember famous quantum physicists repeating in an almost mantra-like fashion that quantum theory, or experimental evidence, 'excludes hidden variables as a possibility', along with a reference to some or other newly found 'impossibility proof'. Yet we also recall John Bell's famous counter-statement: 'What is proved by impossibility proofs is lack of imagination.' In this sense, therefore, our task is to make use of the variety of the different approaches offered, for it is in scrutinizing each of them that a chance for further progress and understanding may emerge. The papers collected in these proceedings essentially follow the order of the plenary talks during the conference program, with the addition of the poster presentations. Prior to the contributions to EmerQuM11, the very first paper of these proceedings presents the opening lecture by Yves Couder who addressed both twin conferences with his talk on wave-particle duality in a classical system. (Although he was not able to participate personally, the contribution of Robert Carroll, a member of the academic advisory board, is included here. Regrettably, the lectures by John Bush, Marek Czachor, Mark Everitt, Felix Finster, and Lee Smolin could not be included, partly for copyright reasons.) Finally, I would like to thank Sarah Toms and Graham Douglas and their team at IOP Publishing (Bristol) for their friendly advice and help during the preparation of these proceedings. Vienna, April 2012 Gerhard Gr?ssing
These proceedings comprise the plenary lectures and poster contributions of the 'Heinz von Foerster Conference 2011' on Emergent Quantum Mechanics (EmerQuM11), which was held at the University of Vienna, 11?13 November 2011. With the 5th International Heinz von Foerster Conference convened at the occasion of von Foerster's 100th birthday, the organizers opted for a twin conference to take place at the Large and Small Ceremonial Halls of the University's main building, respectively. The overall topic was chosen as 'Self-Organization and Emergence', a topic to which von Foerster was an early contributor. While the first conference ('Self-Organization and Emergence in Nature and Society') addressed a more general audience, the second one ('Emergent Quantum Mechanics') was intended as a specialist meeting with a contemporary topic that could both serve as an illustration of von Foerster's intellectual heritage and, more generally, point towards future directions in physics. We thus intended to bring together many of those physicists who are interested in or are working on attempts to understand quantum mechanics as emerging from a suitable classical (or, more generally, deeper level) physics. EmerQuM11 was organized by the Austrian Institute for Nonlinear Studies (AINS), with essential support from the Wiener Institute for Social Science Documentation and Methodology (WISDOM), the Department of Contemporary History at the University of Vienna, and the Heinz von Foerster-Gesellschaft. There were a number of individuals who contributed to the smooth course of our meeting and whom I would like to sincerely thank: Christian Bischof, Thomas Elze, Marianne Ertl, Gertrud Hafner, Werner Korn, Angelika Krawanja, Florian Krug and his team, Sonja Lang, Albert M?ller, Ilse M?ller, Irene M?ller, Karl M?ller, Armin Reautschnig, Marion Schirrmacher, Anton Staudinger, Roman Zlabinger, and, last but not least, my AINS colleagues Siegfried Fussy, Herbert Schwabl and Johannes Mesa Pascasio, the latter in particular for his invaluable technical help with these proceedings. Funds made available by the Federal Ministry of Science and Research (BMWF), the City of Vienna MA7 Science Funding, the Faculty of Historical and Cultural Studies, Blaha Office Furniture, and Padma AG Zurich are gratefully acknowledged. As for the nature of the search for a 'deeper level' foundation of quantum mechanics, a first difficulty already arises with respect to the question: Where do we start? One may look for quite different points of departure, such as an encompassing theory of quantum gravity. Or one may find arguments for the necessity to base one's approach at least on a relativistic formulation of the problem. Or one may discard searching for general principles for the time being, and develop an explicit physical model first. And so on. In fact, this is actually what is happening today in different research programs for emergent quantum mechanics, a fact which is also reflected in the rich variety of approaches presented at our meeting. This may be considered a very welcome situation, reminding us of Heinz von Foerster's dictum: 'Act always so as to increase the number of choices.' However, some may view this variety also as a drawback: There is not (yet?) a single, definite alternative theory that would challenge orthodox positions, for example, by providing different experimental predictions. However, the prevailing orthodoxy has shown throughout the 20th century to the present day, that a too restrictive attitude towards theoretical alternatives can lead to almost a standstill in coping with the serious shortcomings and contradictions of present-day physics. Many of us remember famous quantum physicists repeating in an almost mantra-like fashion that quantum theory, or experimental evidence, 'excludes hidden variables as a possibility', along with a reference to some or other newly found 'impossibility proof'. Yet we also recall John Bell's famous counter-statement: 'What is proved by impossibility proofs is lack of imagination.' In this sense, therefore, our task is to make use of the variety of the different approaches offered, for it is in scrutinizing each of them that a chance for further progress and understanding may emerge. The papers collected in these proceedings essentially follow the order of the plenary talks during the conference program, with the addition of the poster presentations. Prior to the contributions to EmerQuM11, the very first paper of these proceedings presents the opening lecture by Yves Couder who addressed both twin conferences with his talk on wave-particle duality in a classical system. (Although he was not able to participate personally, the contribution of Robert Carroll, a member of the academic advisory board, is included here. Regrettably, the lectures by John Bush, Marek Czachor, Mark Everitt, Felix Finster, and Lee Smolin could not be included, partly for copyright reasons.) Finally, I would like to thank Sarah Toms and Graham Douglas and their team at IOP Publishing (Bristol) for their friendly advice and help during the preparation of these proceedings. Vienna, April 2012 Gerhard Gr?ssing
These proceedings present the Invited Lectures and Contributed Papers of the Fourth International Workshop on Decoherence, Information, Complexity and Entropy – DICE 2008, held at Castello Pasquini, Castiglioncello (Tuscany), 22–26 September 2008. We deliver these proceedings as a means to document to the interested public, to the wider scientific community, and to the participants themselves the stimulating exchange of ideas at this conference. The steadily growing number of participants, among them acclaimed scientists in their respective fields, show its increasing attraction and a fruitful concept, based on bringing leading researchers together and in contact with a mix of advanced students and scholars. Thus, this series of meetings successfully continued from the beginning with DICE 2002, (Decoherence and Entropy in Complex Systems ed H-T Elze Lecture Notes in Physics 633 (Berlin: Springer, 2004)) followed by DICE 2004 (Proceedings of the Second International Workshop on Decoherence, Information, Complexity and Entropy – DICE 2004 ed H-T Elze Braz. Journ. Phys. 35, 2A & 2B (2005) pp 205–529; free access at: www.sbfisica.org.br/bjp) and by DICE 2006, (Proceedings of the Third International Workshop on Decoherence, Information, Complexity and Entropy – DICE 2006 eds H-T Elze, L Diosi and G Vitiello Journal of Physics: Conference Series 67 (2007); free access at: http://www.iop.org/EJ/toc/1742-6596/67/1) uniting about one hundred participants from more than twenty different countries worldwide this time. It has been a great honour and inspiration for all of us to have Professor Sir Roger Penrose from the Mathematical Institute at the University of Oxford with us, who presented the lecture ``Black holes, quantum theory and cosmology'' (included in this volume). Discussions under the wider theme ``From Quantum Mechanics through Complexity to Spacetime: the role of emergent dynamical structures'' took place in the very pleasant and inspiring atmosphere of Castello Pasquini, which – with its beautiful surroundings, overlooking a piece of Tuscany's coast, and with splendid weather throughout – was conducive to the success of the meeting. The 5-day program was grouped according to the following topics: Quantum Physics and Some Important Questions it Raises Emergent Dynamics, from Quantum to Brain and Beyond Exploring Quantum Mechanics Atomistic Theories of Spacetime Quantum-Entanglement/Gravity/Cosmology A Public Roundtable Discussion formed an integral part of the program under the theme ``Dialoghi sulla complessita' – dall' atomo all' Universo'' and with the participation of physicists and philosophers: F T Arecchi (Firenze), L Fronzoni (Pisa), A M Iacono (Pisa), F Luccio (Pisa) and G Vitiello (Salerno, coordinator). This event drew a large audience, who participated in the lively discussions until late in the evening. The workshop has been organized by L Diosi (Budapest), H-T Elze (Pisa, chair), L Fronzoni (Pisa), J Halliwell (London) and G Vitiello (Salerno), with great help from our conference secretaries M Pesce-Rollins (Siena) and L Baldini (Pisa) and from our students F Caravelli and E Di Nardo, both from Pisa. Several institutions and sponsors generously supported the workshop and their representatives and, in particular, the citizens of Rosignano/Castiglioncello are deeply thanked for the help and kind hospitality: Comune di Rosignano A Nenci (Sindaco di Rosignano), S Scarpellini (Segreteria sindaco), D Del Seppia (Assessore allo Sviluppo Economico del Comune di Rosignano), A Franchi (Assessore al turismo del Comune di Rosignano/Presidente dell' associazione Armunia), A Corsini (Ufficio economato del Comune di Rosignano). REA Rosignano Energia Ambiente s.p.a. F Ghelardini (Presidente della REA), A Cecchini (Ufficio - Responsabile stampa della REA). Solvay Chimica Italia s.a. Dott S Piccoli (Responsabile Relazioni Esterne, Solvay Rosignano), G Becherucci (Comunicazione e Relazioni Esterne). Associazione Armunia M Paganelli (Direttore), G Mannari (Programmazione). Special thanks go to G Mannari for her advice and great help in all the many practical matters that had to be dealt with, in order to run the meeting at Castello Pasquini smoothly. Funds made available by Universita di Pisa, by Domus Galilaeana (Pisa), Centro Interdisciplinare per lo Studio dei Sistemi Complessi – CISSC (Pisa), Dipartimento di Matematica e Informatica (Universita di Salerno), Istituto Italiano per gli Studi Filosofici – IISF (Napoli), and by IOP Publishing (Bristol) are gratefully acknowledged. Last but not least, special thanks go to L Pesce (Vitrium Galleria, Populonia) for her artwork (``Art and Science'') displayed during the conference at Castello Pasquini. The research papers presented at the workshop, often incorporating further developments since then, or presenting original new work, have been edited by L Diosi, H-T Elze, L Fronzoni, J J Halliwell and G Vitiello, with major assistance from J Yearsley (London), which we gratefully acknowledge. They are collected here, essentially following the program of the workshop, however, divided into Invited Lectures (we regret that lectures by E Arimondo, N Gisin, and W Schleich could not be reproduced here) and Contributed Papers, respectively. In the name of all participants, we would like to thank Dr J Schwarz and G Douglas (IOP Publishing, Bristol), and their collaborators, for friendly advice, always immediate help during the editing process, and for their efforts making the Journal of Physics: Conference Series available to all. Budapest, Pisa, London and Salerno, May 2009 Lajos Diosi, Hans-Thomas Elze, Leone Fronzoni, Jonathan Halliwell and Giuseppe Vitiello
Delivered at Trieste on the occasion of the 25th Anniversary of the International Centre for Theoretical Physics, 2 November 1989 The video of this lecture is available here . Please see the PDF for the transcript of the lecture. General remarks by Angelo Bassi and GianCarlo Ghirardi During the autumn of 1989 the International Centre for Theoretical Physics, Trieste, celebrated the 25th anniversary of its creation. Among the many prestigious speakers, who delivered extremely interesting lectures on that occasion, was the late John Stewart Bell. All lectures have been recorded on tape. We succeeded in getting a copy of John's lecture. In the lecture, many of the arguments that John had lucidly stressed in his writings appear once more, but there are also extremely interesting new remarks which, to our knowledge, have not been presented elsewhere. In particular he decided, as pointed out by the very choice of the title of his lecture, to call attention to the fact that the theory presents two types of difficulties, which Dirac classified as first and second class. The former are those connected with the so-called macro-objectification problem, the latter with the divergences characterizing relativistic quantum field theories. Bell describes the precise position of Dirac on these problems and he stresses appropriately how, contrary to Dirac's hopes, the steps which have led to a partial overcoming of the second class difficulties have not helped in any way whatsoever to overcome those of the first class. He then proceeds to analyse the origin and development of the Dynamical Reduction Program and draws attention to the problems that still affect it, in particular that of a consistent relativistic generalization. When the two meetings Are there quantum jumps? and On the present status of Quantum Mechanics were organized in Trieste and Losinj (Croatia), on 5–10 September 2005, it occurred to us that this lecture, which has never been published, might represent an extremely interesting historical record for all the participants who certainly shared with us a great admiration for this outstanding scientist and deep thinker. Accordingly, with the permission of the Abdus Salam International Centre for Theoretical Physics, and with thanks to the financial support of the Consorzio per la Fisica of the Trieste University, we have produced from the original record a DVD which has been given to all participants although, unfortunately, the video tape of the event was not particularly good. Taking into account that the participants to the meetings represented only a very small subset of those scientists who might be interested in hearing what John Bell said in probably his last lecture, we considered that it would be useful for the scientific community interested in foundational problems to publish the text of this lecture in order to make it accessible to everybody. The lecture was preceded by a presentation by the Chairman, Alain Aspect, which we have also included. Due to the aforementioned low quality of the recording it has not been easy to pass from the tape to the text we are presenting below, and we have to thank, for her precious collaboration, Dr Julia Filingeri who did most of the work, as well as Mrs Anne Gatti from ICTP, Professors Detlef Düurr and Sheldon Goldstein, and the staff of IOP Publishing who contributed in an essential way in deciphering some particularly difficult passages. Obviously, we take full responsibility for any possible inappropriate rendering of the original talk. We thank the Abdus Salam International Centre for Theoretical Physics for authorizing IOP Publishing to publish this important document. Some final remarks are in order. Firstly, we have put in square brackets parenthetical remarks that John made while reading sentences from his transparencies. We have also indicated by parenthetical ellipsis (...) very short parts of the speech (usually one word) which we have not been able to decipher. We have included a picture (figure 1) shown by him, taking it from the tape image which is of rather poor quality (we apologize for this) and three figures taken from his transparencies. Moreover, to help the reader in grasping the various points John Stewart Bell brilliantly raised in his talk we have divided the paper into six sections whose titles have been chosen by us to summarize the most crucial points of his argument. Presentation by the Chairman, Alain Aspect It is a great pleasure and an honour to introduce Professor Bell. When looking to my old papers I discovered that this 25th anniversary of the ICTP also coincides with the famous paper in which appeared, for the first time, inequalities that are now known as Bell's inequalities so it's a very good opportunity to have a talk by John Bell here. Many of us have been strongly influenced by this work of John Bell because he has shown us that quantum mechanics is much more difficult to understand that we thought it was. I am sure that today he will again raise some questions which are very embarrassing but that we have definitely to face.
This special issue of Journal of Physics A: Mathematical and Theoretical appears on the occasion of the 5th International Symposium on Quantum Theory and Symmetries (QTS5), held in Valladolid, Spain, from 22–28 July 2007. This is the fith in a series of conferences previously held in Goslar (Germany) 1999, QTS1; Cracow (Poland) 2001, QTS2; Cincinnati (USA) 2003, QTS3; and Varna (Bulgaria) 2005, QTS4. The QTS5 symposium gathered 181 participants from 39 countries working in different fields of theoretical physics. The spirit of the QTS conference series is to join researchers in a wide variety of topics in theoretical physics, as a way of making accessible recent results and the new lines of different fields. This is based on the feeling that it is good for a physicist to have a general overview as well as expertise in his/her own field. There are many other conferences devoted to specific topics, which are of interest to gain deeper insight in many technical aspects and that are quite suitable for discussions due to their small size. However, we believe that general conferences like this are interesting and worth keeping. We like the talks, in both plenary and parallel sessions, which are devoted to specific topics, to be prepared so as to be accessible to any researcher in any branch of theoretical physics. We think that this objective is compatible with rigour and high standards. As is well known, similar methods and techniques can be useful for many problems in different fields. We hope that this has been appreciated during the sessions of the QTS5 conference. The QTS5 conference offered the following list of topics: 1. Symmetries in string theory, quantum gravity and related topics 2. Symmetries in quantum field theories, conformal and related field theories, lattice and noncommutative theories, gauge theories 3.Quantum computing, information and control 4. Foundations of quantum theory 5. Quantum optics, coherent states, Wigner functions 6. Dynamical and integrable systems 7. Symmetries in condensed matter and statistical physics 8. Symmetries in particle physics, nuclear, atomic and molecular physics 9. Nonlinear quantum mechanics 10. Time asymmetric quantum mechanics 11. SUSY quantum mechanics, PT symmetries and pseudo-Hamiltonians 12. Mathematical methods for symmetries and quantum theories 13. Symmetries in chemistry, biology and other sciences Papers accepted for publication in this issue aim to provide a survey of the state of the art in different fields and contain contributions from plenary speakers. In addition, the issue contains contributions from other participants and it has also been open to other authors whose work fits into the topics of the conference. In any case, all the contributions have been refereed according to the high standards of Journal of Physics A: Mathematical and Theoretical . We are much indebted to several institutions; without their support the organization of the QTS5 symposium would not have been possible. In this respect we acknowledge the Ministerio de Educación of Spain and Junta de Castilla y León for general financial support; to Fundación Universidades de Castilla y León for a number of grants to young researchers who otherwise would not have attended the conference; also to the European Physical Society that provided a number of grants for eastern countries, and to the University of Valladolid where the event took place. We thank IOP Publishing and the staff of Journal of Physics A: Mathematical and Theoretical for the publication of this special issue. In addition, we want to express our gratitude to other members of the Local Organizing Committe of QTS5, who are not Editors of this special issue: Oscar Arratia, Juan A Calzada and Fernando Gómez. Finally, we would like to thank all the participants in the QTS5 conference for their presence, contributions, and for the good atmosphere achieved during their stay. We hope that the experience of spending these days in Valladolid has been most fruitful for all of them.