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Electroweak Symmetry Breaking As of 2003, on the Way to the Large Hadron Collider 1 Riccardo Barbieri

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Electroweak Symmetry Breaking As of 2003, on the Way to the Large Hadron Collider 1 Riccardo Barbieri Particle Physics and Cosmology: The Interface NATO Science Series A Series presenting the results of scientific meetings supported under the NATO Science Programme. The Series is published by IOS Press, Amsterdam, and Springer (formerly Kluwer Academic Publishers) in conjunction with the NATO Public Diplomacy Division. Sub-Series I. Life and Behavioural Sciences IOS Press II. Mathematics, Physics and Chemistry Springer (formerly Kluwer Academic Publishers) III. Computer and Systems Science IOS Press IV. Earth and Environmental Sciences Springer (formerly Kluwer Academic Publishers) The NATO Science Series continues the series of books published formerly as the NATO ASI Series. The NATO Science Programme offers support for collaboration in civil science between scientists of countries of the Euro-Atlantic Partnership Council. The types of scientific meeting generally supported are “Advanced Study Institutes” and “Advanced Research Workshops”, and the NATO Science Series collects together the results of these meetings. The meetings are co-organized by scientists from , NATO countries and scientists from NATO s Partner countries – countries of the CIS and Central and Eastern Europe. Advanced Study Institutes are high-level tutorial courses offering in-depth study of latest advances in a field. Advanced Research Workshops are expert meetings aimed at critical assessment of a field, and identification of directions for future action. As a consequence of the restructuring of the NATO Science Programme in 1999, the NATO Science Series was re-organized to the four sub-series noted above. Please consult the following web sites for information on previous volumes published in the Series. http://www.nato.int/science http://www.springeronline.com http://www.iospress.nl Series II: Mathematics, Physics and Chemistry – Vol. 188 Particle Physics and Cosmology: The Interface edited by D. Kazakov JINR, Dubna and ITEP, Moscow, Russia and G. Smadja Université Claude Bernard, Lyon 1, France Published in cooperation with NATO Public Diplomacy Division Proceedings of the NATO Advanced Study Institute on Particle Physics and Cosmology: The Interface Cargèse, France 4– 16 August 2003 A C.I.P.Catalogue record for this book is available from the Library of Congress. ISBN 1-4020-3160-2 (PB) ISBN 1-4020-3159-9 (HB) ISBN 1-4020-3161-0 (e-book) Published by Springer, P.O. Box 17, 3300 AA Dordrecht, The Netherlands. Sold and distributed in North, Central and South America by Springer, 101 Philip Drive, Norwell, MA 02061, U.S.A. In all other countries, sold and distributed by Springer, P.O. Box 322, 3300 AH Dordrecht, The Netherlands. Printed on acid-free paper All Rights Reserved © 2005 Springer No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Printed in the Netherlands. Contents Contributing Authors vii Foreword ix Preface xi Acknowledgments xii ElectroWeak Symmetry Breaking as of 2003, on the way to the Large Hadron Collider 1 Riccardo Barbieri Current Status of the CKM Matrix and the CP Violation 31 Achille Stocchi Neutrino Masses 83 Stefan Pokorski Neutrinos 111 Jacques Bouchez Baryo- and Leptogenesis (outline) 171 Wilfried Buchm¨uller Scalar Fields in Particle Physics in Cosmology 181 Pierre Binetruy Inflation, Quantum Fluctuations and Cosmological Perturbations 235 David Langlois Cosmic Microwave Background Cosmology; New Economy Model Universe 279 George F. Smoot Cosmology with Supernovae 1a 311 Smadja G´erard v vi PARTICLE PHYSICS AND COSMOLOGY: THE INTERFACE Dark Matter and Galaxy Formation 329 Joseph Silk Supersymmetric Extension of the Standard Model 349 Dimitri Kazakov Gaugino Condensation and SUSY Breakdown 397 Hans Peter Nilles Is Dark Matter Supersymmetric? 435 Wim de Boer Cargese Lectures on Extra-Dimensions 461 Riccardo Rattazzi Contributing Authors Riccardo Barbieri Professor at Scuole Normale Superiore, Pisa Pierre Binetruy Professor at University Paris 11 and Paris 7 Jacques Bouchez Research staff at DAPNIA, CEN Saclay Wilfried Buchmuller Professor at the University of Hamburg and DESY staff. Wim De Boer Professor at the University of Karlsruhe Dimitri Kazakov Research staff at JINR (Dubna) and ITEP (Moscow, Russia) David Langlois Research staff at IAP (Paris) Hans-Peter Nilles Professor at the university of Bonn Stefan Pokorski Professor at the University of Warsaw Riccardo Rattazzi Research staff at CERN (Geneva) Joseph Silk Professor at the University of Oxford Gerard Smadja Professor at the University Claude Bernard (Lyon 1) George Smoot Professor at the University of California at Berkeley Achille Stocchi Research staff at LAL-Orsay (CNRS) vii Foreword This Carg`ese school of Particle physics is meant to bridge the narrow- ing gap between astrophysical observations and particle physics. The lectures supply the students with a theoretical background which covers several aspects of the cosmological scenario: matter-antimatter asymme- try, the nature of dark matter, the acceleration of the expansion and the cosmological constant and the geometry of the universe as well as mod- ern views on particle physics including supersymmetry, extra dimensions scenarii and neutrino oscillations. ix Preface The investigation of nuclear abundances by Alpher, Bethe, and Gamow (1948) was the first intrusion of subatomic physics into cosmology. In contrast with their assumption, most nuclear species are now known to be produced in stars, but their bold step led to predictions which have largely been proven to be right: -a crude estimate of the densities during primordial nucleosynthesis -the presence of a residual 3K radiation today. the issues they addressed are still relevant. The origin of matter is not fully understood,and the CMB has grown into a powerful tool to inves- tigate the early eras of the universe. The progress of cosmological observations has now led to a ’standard’ slow-roll inflation model, which accounts quantitatively for many ob- served features of the universe. As the lectures will show, it still leaves large unchartered areas, and the underlying particle physics aspects are yettobeelucidated. At the same time despite the unprecedented success of the Stan- dard Model of fundamental interactions there are still remaining ”white spots”. Possible physics beyond the SM may have its manifestation in astrophysics and cosmology which may serve as a sky laboratory to reveal the new features of the microworld. The present volume contains the collection of lectures on the hottest topics in particle physics and cosmology given by the experts which describe the modern status and the perspectives of development of ex- perimental and theoretical activities in these fields. xi Acknowledgments The school has been supported by the following institutions: NATO, CNRS (Formation permanente, IN2P3, INSU/PNC, Collectivit´e Territoriale Corse, DAPNIA/CEN-Saclay We also want to acknowledge the major contribution of the IPNL staff who helped organize the school: M. Chartoire, M. Croiz´e, D. Jarroux- D´eclais, S. Flor`es, and Anne-Marie Ferrer, who took care of all finan- cial problems. At the Carg`ese Institute, Brigitte Cassegrain, Nathalie Bedjai, and Pierre Grossi were very helpful and ensured the smooth operation of the lectures and the distribution of the teaching material. xii ELECTROWEAK SYMMETRY BREAKING AS OF 2003, ON THE WAY TO THE LARGE HADRON COLLIDER∗ Riccardo Barbieri Scuola Normale Superiore and INFN, Pisa, Italy [email protected] Abstract I review the status of the ElectroWeak Symmetry Breaking problem. The lectures are naturally divided into two parts. The first is mostly de- voted to overview the impact of current data on the issue of EWSB. The tools are known, the latest data are included. Always in the first part, I say why I care about the ”little hierarchy” problem and I summarize how some proposals for EWSB, recent and less recent, are confronted with this problem. Motivated by these considerations, in the second part I describe the essential features of a proposal for breaking super- symmetry, and consequently the electroweak symmetry, by boundary conditions on an extra dimension. Keywords: Electroweak, Symmetry, Breaking, Higgs mass, Supersymmetry, Kaluza- Klein, MSSM The data (their interpretation) summarized There are several good reasons for being interested in the problem of how the electroweak symmetry gets broken. Above all, the physical origin of the Fermi scale has not been identified, yet. Consequently, and not less importantly, this ignorance acts as a cloud on every attempt to design a theory of the fundamental interactions beyond the Standard Model (SM). Last, but not least, the exploration of the TeV scale of energy expected at the Large Hadron Collider (LHC) should finally allow ∗Lectures given at the Cargese School of Physics and Cosmology - August 2003 - Cargese - France 1 D. Kazakov and G. Smadja (eds.), Particle Physics and Cosmology: The Interface, 1–29. © 2005 Springer. Printed in the Netherlands. 2 PARTICLE PHYSICS AND COSMOLOGY: THE INTERFACE a direct comparison with experiment of every theoretical idea on this matter. These are not the first lectures on the subject of ElectroWeak Sym- metry Breaking (EWSB). Nevertheless, I find that it may be useful to overview the present status of the subject when we still have a few years before the start of the LHC and when the program of the ElectroWeak Precision Tests (EWPT), in particular with the completion of most of the data analyses by the LEP experiments, is in a mature stage. The EWPT are still the most important source of experimental in- formation, although indirect, on EWSB. It so happens that I already lectured in Cargese on the EWPT in 1992, when the accumulation of significant experimental results on the EWPT was about to start and the top quark had not yet been discovered. At that time the bulk of the radiative effects seen in the data was still of electromagnetic origin.
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