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
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
Presented in this volume are the Invited Lectures and the Contributed Papers of the Seventh International Workshop on Decoherence, Information, Complexity and Entropy – DICE 2014 , held at Castello Pasquini, Castiglioncello (Tuscany), September 15-19, 2014. These proceedings are intended to reflect the lively exchange of ideas during the meeting for the interested public and the wider scientific community, as well as to provide a document of the scientific works presented. The number of participants has continued to grow, which may correspond to an increasing attraction, if not need, of such conference: Our very intention has always been to bring together leading researchers, advanced students, and renowned scholars from various areas, in order to stimulate new ideas and their exchange across the borders of specialization. In this way, the series of meetings successfully continued from the beginning with DICE 2002, followed by DICE 2004, DICE 2006, DICE 2008, DICE 2010, and DICE 2012. This time, DICE 2014 brought together more than 120 participants representing more than 30 countries. It has been a great honour and inspiration that we had with us Nobel Prize laureate Gerard 't Hooft (Utrecht - Keynote Lecture ''The Cellular Automaton Interpretation and Bell's Theorem'' ), Fields Medal winner Alain Connes (Paris - Keynote Lecture ''Quanta of geometry'' ), Professor Avshalom Elitzur (Rehovot - Keynote Lecture ''Voices of silence, novelties of noise: on some quantum hairsplitting methods with nontrivial consequences'', in this volume) and Professor Mario Rasetti (Torino - Keynote Lecture ''The topological field theory of data: a possible new venue for data mining'' , in this volume). The opening Keynote Lecture ''History of electroweak symmetry breaking'' was presented by Sir Tom Kibble (London), co-discoverer of the Higgs mechanism, Sakurai Prize laureate and winner of, i.a., Dirac and Einstein Medals.
The application of quantum mechanics to information related fields such as communication, computation and cryptography is a fast growing line of research that has been witnessing an outburst of theoretical and experimental results, with possible practical applications. On the one hand, quantum cryptography with its impact on secrecy of transmission is having its first important actual implementations; on the other hand, the recent advances in quantum optics, ion trapping, BEC manipulation, spin and quantum dot technologies allow us to put to direct test a great deal of theoretical ideas and results. These achievements have stimulated a reborn interest in various aspects of quantum mechanics, creating a unique interplay between physics, both theoretical and experimental, mathematics, information theory and computer science. In viewof all these developments, it appeared timely to organize a meeting where graduate students and young researchers could be exposed to the fundamentals of the theory, while senior experts could exchange their latest results. The activity was structured as a school followed by a workshop, and took place at The Abdus Salam International Center for Theoretical Physics (ICTP) and The International School for Advanced Studies (SISSA) in Trieste, Italy, from 12–23 June 2006. The meeting was part of the activity of the Joint European Master Curriculum Development Programme in Quantum Information, Communication, Cryptography and Computation, involving the Universities of Cergy–Pontoise (France), Chania (Greece), Leuven (Belgium), Rennes1 (France) and Trieste (Italy). This special issue of Journal of Physics A: Mathematical and Theoretical collects 22 contributions from well known experts who took part in the workshop. They summarize the present day status of the research in the manifold aspects of quantum information. The issue is opened by two reviewarticles, the first byGAdesso and F Illuminati discussing entanglement in continuous variable systems, the second by T Prosen, discussing chaos and complexity in quantum systems. Both topics have theoretical as well as experimental relevance and are likely to witness a fast growing development in the near future. The remaining contributions present more specific and very recent results. They involve the study of the structure of quantum states and their estimation (B Baumgartner et al, C King et al, S Olivares et al, D Petz et al and W van Dam et al), of entanglement generation and its quantification (G Brida et al, F Ciccarello et al, G Costantini et al, O Romero-Isart et al, D Rossini et al, A Serafini et al and D Vitali et al), of randomness related effects on entanglement behaviour (I Akhalwaya et al, O Dahlsten et al and L Viola et al), and of abstract and applied aspects of quantum computation and communication (K Audenart, G M D'Ariano et al, N Datta et al, L C Kwek et al and M Nathanson et al). We would like to express our gratitude to the European Commission, the Abdus Salam ICTP, SISSA and Eurotech SpA (Amaro, Udine, Italy) for financial and/or logistic support. Special thanks also go to the workshop secretary Marina De Comelli, and the secretaries of the Department of Theoretical Physics, University of Trieste, Sabrina Gaspardis and Rosita Glavina for their precious help and assistance.
The application of quantum mechanics to information related fields such as communication, computation and cryptography is a fast growing line of research that has been witnessing an outburst of theoretical and experimental results, with possible practical applications. On the one hand, quantum cryptography with its impact on secrecy of transmission is having its first important actual implementations; on the other hand, the recent advances in quantum optics, ion trapping, BEC manipulation, spin and quantum dot technologies allow us to put to direct test a great deal of theoretical ideas and results. These achievements have stimulated a reborn interest in various aspects of quantum mechanics, creating a unique interplay between physics, both theoretical and experimental, mathematics, information theory and computer science. In view of all these developments, it appeared timely to organize a meeting where graduate students and young researchers could be exposed to the fundamentals of the theory, while senior experts could exchange their latest results. The activity was structured as a school followed by a workshop, and took place at The Abdus Salam International Center for Theoretical Physics (ICTP) and The International School for Advanced Studies (SISSA) in Trieste, Italy, from 12–23 June 2006. The meeting was part of the activity of the Joint European Master Curriculum Development Programme in Quantum Information, Communication, Cryptography and Computation, involving the Universities of Cergy–Pontoise (France), Chania (Greece), Leuven (Belgium), Rennes1 (France) and Trieste (Italy). This special issue of Journal of Physics A: Mathematical and Theoretical collects 22 contributions from well known experts who took part in the workshop. They summarize the present day status of the research in the manifold aspects of quantum information. The issue is opened by two review articles, the first by G Adesso and F Illuminati discussing entanglement in continuous variable systems, the second by T Prosen, discussing chaos and complexity in quantum systems. Both topics have theoretical as well as experimental relevance and are likely to witness a fast growing development in the near future. The remaining contributions present more specific and very recent results. They involve the study of the structure of quantum states and their estimation (B Baumgartner et al , C King et al , S Olivares et al , D Petz et al and W van Dam et al ), of entanglement generation and its quantification (G Brida et al , F Ciccarello et al , G Costantini et al , O Romero-Isart et al , D Rossini et al , A Serafini et al and D Vitali et al ), of randomness related effects on entanglement behaviour (I Akhalwaya et al , O Dahlsten et al and L Viola et al ), and of abstract and applied aspects of quantum computation and communication (K Audenart, G M D'Ariano et al , N Datta et al , L C Kwek et al and M Nathanson et al ). We would like to express our gratitude to the European Commission, the Abdus Salam ICTP, SISSA and Eurotech SpA (Amaro, Udine, Italy) for financial and/or logistic support. Special thanks also go to the workshop secretary Marina De Comelli, and the secretaries of the Department of Theoretical Physics, University of Trieste, Sabrina Gaspardis and Rosita Glavina for their precious help and assistance.
The fourth International Workshop on `Mysteries, Puzzles and Paradoxes in Quantum Mechanics' was held from 27 August to 1 September 2001, at the Palazzo Feltrinelli in Gargnano, Italy, as were the first three, on the shore of Lake Garda. It continued the tradition of the previous workshops in seeking a deeper understanding of the foundations of quantum mechanics. After more than 75 years, this field of investigation is still active and able to stimulate both intense discussions and interesting physics research, involving many physicists from quite different fields. For that reason, this special issue of Journal of Optics B: Quantum and Semiclassical Optics confronts many different aspects of quantum mechanics, as afforded from many different points of view. There is, however, a common theme pervading all the contributions, which provided the main focus of this workshop, namely, interference. We have followed Richard Feynman, according to whom quantum interference is a `phenomenon which is impossible, absolutely impossible, to explain in any classical way, and which has in it the heart of quantum mechanics. In reality it contains the only mystery.' The workshop investigated many aspects of interference phenomena in various fields of optical, atomic and molecular physics. The progressive degradation of interference effects, i.e. quantum decoherence, was also investigated in its various forms, both experimentally and theoretically. In fact, this special issue demonstrates another distinguishing feature of the series of `Mysteries, Puzzles and Paradoxes in Quantum Mechanics', namely, the close connection between theoretical and experimental contributions. This strong interconnection is becoming more and more important nowadays, because of the impressive technological advances which have made it possible to verify experimentally in a laboratory what the founding fathers of quantum mechanics considered only as `Gedanken' experiments. The intense debate and lively atmosphere of the workshop is reflected by the 44 contributions to this special issue, involving more than 90 authors. We would like to give special thanks to Giovanna La Pietra, the real cornerstone of all four of the workshops; without her continuous assistance, they would have not been possible. Finally, special thanks are due to the Scientific Secretary of the workshop, Dr Stefano Olivares, for his invaluable help, both in organizing the meeting and in the preparation of this special issue. Rodolfo Bonifacio Università di Milano, Italy David Vitali Università di Camerino, Italy Guest Editors