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The Subnuclear Series • Volume 39 Proceedings of the International School of Subnuclear Physics NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS Edited by Antonino Zichichi World Scientific The Subnuclear Series • Volume 39 Proceedings of the International School of Subnuclear Physics NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS THE SUBNUCLEAR SERIES Series Editor: ANTONINO ZICHICHI, European Physical Society, Geneva, Switzerland 1. 1963 STRONG, ELECTROMAGNETIC, AND WEAK INTERACTIONS 2. 1964 SYMMETRIES IN ELEMENTARY PARTICLE PHYSICS 3. 1965 RECENT DEVELOPMENTS IN PARTICLE SYMMETRIES 4. 1966 STRONG AND WEAK INTERACTIONS 5. 1967 HADRONS AND THEIR INTERACTIONS 6. 1968 THEORY AND PHENOMENOLOGY IN PARTICLE PHYSICS 7. 1969 SUBNUCLEAR PHENOMENA 8. 1970 ELEMENTARY PROCESSES AT HIGH ENERGY 9. 1971 PROPERTIES OF THE FUNDAMENTAL INTERACTIONS 10. 1972 HIGHLIGHTS IN PARTICLE PHYSICS 11. 1973 LAWS OF HADRONIC MATTER 12. 1974 LEPTON AND HADRON STRUCTURE 13. 1975 NEW PHENOMENA IN SUBNUCLEAR PHYSICS 14. 1976 UNDERSTANDING THE FUNDAMENTAL CONSTITUENTS OF MATTER 15. 1977 THE WHYS OF SUBNUCLEAR PHYSICS 16. 1978 THE NEW ASPECTS OF SUBNUCLEAR PHYSICS 17. 1979 POINTLIKE STRUCTURES INSIDE AND OUTSIDE HADRONS 18. 1980 THE HIGH-ENERGY LIMIT 19. 1981 THE UNITY OF THE FUNDAMENTAL INTERACTIONS 20. 1982 GAUGE INTERACTIONS: Theory and Experiment 21. 1983 HOW FAR ARE WE FROM THE GAUGE FORCES? 22. 1984 QUARKS, LEPTONS, AND THEIR CONSTITUENTS 23. 1985 OLD AND NEW FORCES OF NATURE 24. 1986 THE SUPERWORLDI 25. 1987 THE SUPERWORLD II 26. 1988 THE SUPERWORLD III 27. 1989 THE CHALLENGING QUESTIONS 28. 1990 PHYSICS UP TO 200 TeV 29. 1991 PHYSICS AT THE HIGHEST ENERGY AND LUMINOSITY: To Understand the Origin of Mass 30. 1992 FROM SUPERSTRINGS TO THE REAL SUPERWORLD 31. 1993 FROM SUPERSYMMETRY TO THE ORIGIN OF SPACE-TIME 32. 1994 FROM SUPERSTRING TO PRESENT-DAY PHYSICS 33. 1995 VACUUM AND VACUA: The Physics of Nothing 34. 1996 EFFECTIVE THEORIES AND FUNDAMENTAL INTERACTIONS 35. 1997 HIGHLIGHTS OF SUBNUCLEAR PHYSICS: 50 Years Later 36. 1998 FROM THE PLANCK LENGTH TO THE HUBBLE RADIUS 37. 1999 BASICS AND HIGHLIGHTS IN FUNDAMENTAL PHYSICS 38. 2000 THEORY AND EXPERIMENT HEADING FOR NEW PHYSICS 39. 2001 NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS Volume 1 was published by W. A. Benjamin, Inc., New York; 2-8 and 11-12 by Academic Press, New York and London; 9-10 by Editrice Compositon, Bologna; 13-29 by Plenum Press, New York and London; 30-39 by World Scientific, Singapore. The Subnuclear Series • Volume 39 Proceedings of the International School of Subnuclear Physics NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS Edited by Antonino Zichichi European Physical Society Geneva, Switzerland Vfe World Scientific wb New Jersey • London • SI New Jersey • London • Singapore • Hong Kong Published by World Scientific Publishing Co. Pte. Ltd. 5 Toh Tuck Link, Singapore 596224 USA office: Suite 202, 1060 Main Street, River Edge, NJ 07661 UK office: 57 Shelton Street, Covent Garden, London WC2H 9HE Library of Congress Cataloging-in-Publication Data International School of Subnuclear Physics (39th : 2001 : Erice, Italy) New fields and strings in subnuclear physics : proceedings of the International School of Subnuclear Physics / edited by Antonino Zichichi. p. cm. - (The subnuclear series ; v. 39) Includes bibliographical references. ISBN 9812381864 1. String models - Congresses. 2. Gauge fields (Physics) - Congresses. 3. Particles (Nuclear physics) — Congresses. I. Zichichi, Antonino. II. Title. III. Series. QC794.6.S85 157 2001 539.7'2-dc21 2002033156 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. Copyright © 2002 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system now known or to be invented, without written permission from the Publisher. For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA. In this case permission to photocopy is not required from the publisher. Printed in Singapore by Uto-Print PREFACE During August/September 2001, a group of 75 physicists from 51 laboratories in 15 countries met in Erice to participate in the 39th Course of the International School of Subnuclear Physics. The countries represented by the participants were: Argentina, Austria, Canada, China, Denmark, France, Germany, Greece, Hungary, Israel, Italy, Japan, the Netherlands, Poland, Russia, Singapore, Spain, Sweden, United Kingdom, Ukraine and the United States of America. The School was sponsored by the Academies of Sciences of Estonia, Georgia, Lithuania, Russia and Ukraine; the Chinese Academy of Sciences; the Commission of the European Communities; the European Physical Society (EPS); the Italian Ministry of University and Scientific Research (MURST); the Sicilian Regional Government (ERS); the Weizmann Institute of Science; the World Federation of Scientists and the World Laboratory. The purpose of the School was to focus attention on the theoretical and phenomenological developments in String Theory, as well as in all the other sectors of Subnuclear Physics. Experimental highlights were presented and discussed, as reported in the contents. A new feature of the School, introduced in 1996, is a series of special sessions devoted to "New Talents". This is a serious problem in Experimental Physics where collaborations count several hundreds of participants and it is almost impossible for young fellows to be known. Even if with much less emphasis the problem exists also in Theoretical Physics. So we decided to offer the young fellows a possibility to let them be known. Eleven "new talents" were invited to present a paper, followed by a discussion. Three were given the prize: one for the best presentation; one for an original theoretical work; and one for an original experimental work. These special sessions devoted to New Talents represent the projection of Subnuclear Physics on the axis of the young generation. As every year, the discussion sessions have been the focal point of the School's activity. During the organization and the running of this year's Course, I enjoyed the collaboration of two colleagues and friends, Gerardus 't Hooft and Gabriele Veneziano, who shared with me the Directorship of the Course. I would like to thank them, together with the group of invited scientists and all the people who contributed to the success of this year's Course. vi I hope the reader will enjoy the book as much as the students attending the lectures and discussion sessions. Thanks to the work of the Scientific Secretaries, the discussions have been reproduced as faithfully as possible. At various stages of my work I have enjoyed the collaboration of many friends whose contributions have been extremely important for the School and are highly appreciated. I thank them most warmly. A final acknowledgement to all those in Erice, Bologna and Geneva, who have helped me on so many occasions and to whom I feel very indebted. Antonino Zichichi Geneva, October 2001 CONTENTS Mini-Courses on Basics Lattice QCD Results and Prospects 1 R. D. Kenway Non-Perturbative Aspects of Gauge Theories 27 M. A. Shifinan Non-Perturbative String Theory 34 R. H. Dijkgraaf Strings, Branes and New World Scenarios 46 C. Bachas Neutrinos 56 B. Gavelet Legazpi DGLAP and BFKL Equations Now 68 L. N. Lipatov The Puzzle of the Ultra-High Energy Cosmic Rays 91 /. /. Tkachev Topical Seminar The Structure of the Universe and Its Scaling Properties 113 L. Pietronero Experimental Highlights Experimental Highlights from BNL-RHIC 117 W. A. Zajc Experimental Highlights from CERN R. J. Cashmore 124 Highlights in Subnuclear Physics 129 G. Wolf Experimental Highlights from Gran Sasso Laboratory 178 A. Bettini The Anomalous Magnetic Moment of the Muon 215 V. W. Hughes Experimental Highlights from Super-Kamiokande 273 Y. Totsuka Special Sessions for New Talents Helicity of the W in Single-Lepton tt Events 304 F. Canelli Baryogenesis with Four-Fermion Operators in Low-Scale Models 320 T. Dent Is the Massive Graviton a Viable Possibility? 329 A. Papazaglou Energy Estimate of Neutrino-Induced Upgoing Muons 340 E. Scapparone Relative Stars in Randall-Sundrun Gravity 348 T. Wiseman Closing Lecture The Ten Challenges of Subnuclear Physics 354 A. Zichichi Closing Ceremony Prizes and Scholarships 379 Participants 382 1 Lattice QCD Results and Prospects Richard Kenway Department of Physics & Astronomy, The University of Edinburgh, The King's Buildings, Edinburgh EH9 3JZ, Scotland Abstract In the Standard Model, quarks and gluons are permanently confined by the strong interaction into hadronic bound states. The values of the quark masses and the strengths of the decays of one quark flavour into another cannot be mea- sured directly, but must be deduced from experiments on hadrons. This requires calculations of the strong-interaction effects within the bound states, which are only possible using numerical simulations of lattice QCD. These are computa- tionally intensive and, for the past twenty years, have exploited leading-edge computing technology. In conjunction with experimental data from B Factories, over the next few years, lattice QCD may provide clues to physics beyond the Standard Model. These lectures provide a non-technical introduction to lattice QCD, some of the recent results, QCD computers, and the future prospects. 1 The need for numerical simulation For almost 30 years, the Standard Model (SM) has provided a remarkably successful quantitative description of three of the four forces of Nature: strong, electromagnetic and weak. Now that we have compelling evidence for neutrino masses, we are beginning, at last, to glimpse physics beyond the SM. This new physics must exist, because the SM does not incorporate a quantum theory of gravity. However, the fact that no experiment has falsified the SM, despite very high precision measurements, suggests that the essential new physics occurs at higher energies than we can explore today, probably around the TeV scale, which will be accessible to the Large Hadron Collider (LHC). Consequently, the SM will probably remain the most appropriate effective theory up to this scale. QCD is part of the SM. On its own, it is a fully self-consistent quantum field theory of quarks and gluons, whose only inputs are the strength of the coupling between these fields and the quark masses. These inputs are presumably determined by the "Theory of Everything" in which the SM is embedded. For now, we must determine them from experiment, although you will see that to do so involves numerical simulation in an essential way, and this could yet reveal problems with the SM at current energies. Given these inputs, QCD is an enormously rich and predictive theory. With today's algorithms, some of the calculations require computers more powerful than have ever been built, although not beyond the capability of existing technology. [...]... recent being [3]), and the textbook by Montvay and Miinster [4] 2 2.1 Lattice QCD Discretisation and confinement Quantum field theory is a marriage of quantum mechanics and special relativity Quantum mechanics involves probabilities, which in a simulation are obtained by generating many realisations of the field configurations and averaging over them We use the Monte Carlo algorithm for this, having transformed... for simulating u and d quarks, and they offer the exciting possibility of extending numerical simulation to chiral theories and possibly 6 even SUSY theories 2.2 Easily computed quantities Lattice QCD enables us to compute n-point correlation functions, ie expectation values of products of fields at n spacetime points, through evaluating the multiple integrals in equation (1) Using the standard relationship... the t quark mass in lattice QCD since, being so high, it can be determined accurately using perturbation theory 4 Hadron structure The distribution of momenta carried by the partons making up a hadron, ie quarks and gluons, can be calculated from first principles in lattice QCD [14] Since these parton distributions have been obtained experimentally from deep inelastic scattering data, in a regime where... 6-dimensional mesh, allowing the 4-dimensional QCD lattices to be mapped in a wide variety of ways, providing flexibility to repartition a machine without recabling The separate Ethernet tree will be used for booting and loading the machine and for parallel I / O The ASIC design is essentially complete and is undergoing tests We plan to have working chips by October 2002 Our first Tflops-scale machine should be... spacing in physical units, a This requires one further experimental input - a dimensionful quantity which can be related via some power of a to its value computed in lattice units 7 In principle, then, we may tune these parameters so that o -» 0, keeping the quark masses fixed at their real-world values, and keeping the lattice volume fixed by a corresponding increase in the number of lattice points... around 3 MeV, and one d quark, of mass around 6 MeV, yet the proton mass is 938 MeV! The missing 926 MeV is binding energy Lattice QCD has to compute this number and hence provide a rigorous link between the quark masses and the proton mass In the absence of the Theory of Everything to explain the quark masses, we invert this process - take the proton mass from experiment, and use lattice QCD to infer the... Computing Surface in 1990, which sustained 1 Gflops, and thence to the 30 Gflops Cray T3E in 1997 Elsewhere, in recent years, Japan has led the field with two Hitachi machines: a 300 Gflops SR2201 costing $73 per Mflops in 1996, followed by a 600 Gflops SR8000 costing $17 per Mflops per year (it is leased) in 2000 Columbia Univer- 16 sity's QCDSP project [27] produced 120 and 180 Gflops machines at... On a Chip) is a joint project involving Columbia University, the RJKEN Brookhaven Research Centre and UKQCD We are designing and building an Application Specific Integrated Circuit (ASIC) using IBM's Blue Logic embedded processor technology The ASIC contains all of the functionality required for QCD on a single chip It comprises a PowerPC 440 core, a 1 Gflops (peak) 64-bit floating-point unit, 4 MByte... (5) n and so, using results from two-point functions as in equation (3), we can extract matrix elements of operators between single hadron states These govern the decays of a hadron into a final state containing one hadron, eg semileptonic decays such as K — > itev Unfortunately, this analysis doesn't extend simply to decays with two or more hadrons in the final state However, two- and three-point correlation... first Tflops-scale machine should be operational at Columbia early in 2003 and a 5 Tflops sustained version will be installed at Edinburgh by the end of that year A further two machines, sustaining 5 and 10 Tflops, are expected at Brookhaven on the same timescale In parallel, several projects are evaluating Pentium clusters, using commodity interconnects These appear to offer cost-effective smaller systems, . HIGHLIGHTS IN FUNDAMENTAL PHYSICS 38. 2000 THEORY AND EXPERIMENT HEADING FOR NEW PHYSICS 39. 2001 NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS Volume . Singapore. The Subnuclear Series • Volume 39 Proceedings of the International School of Subnuclear Physics NEW FIELDS AND STRINGS IN SUBNUCLEAR PHYSICS