Université Joseph Fourier Les Houches Session LXXXVII 2007
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Inflation, Large Branes, and the Shape of Space
Inflation, Large Branes, and the Shape of Space Brett McInnes National University of Singapore email: [email protected] ABSTRACT Linde has recently argued that compact flat or negatively curved spatial sections should, in many circumstances, be considered typical in Inflationary cosmologies. We suggest that the “large brane instability” of Seiberg and Witten eliminates the negative candidates in the context of string theory. That leaves the flat, compact, three-dimensional manifolds — Conway’s platycosms. We show that deep theorems of Schoen, Yau, Gromov and Lawson imply that, even in this case, Seiberg-Witten instability can be avoided only with difficulty. Using a specific cosmological model of the Maldacena-Maoz type, we explain how to do this, and we also show how the list of platycosmic candidates can be reduced to three. This leads to an extension of the basic idea: the conformal compactification of the entire Euclidean spacetime also has the topology of a flat, compact, four-dimensional space. arXiv:hep-th/0410115v2 19 Oct 2004 1. Nearly Flat or Really Flat? Linde has recently argued [1] that, at least in some circumstances, we should regard cosmological models with flat or negatively curved compact spatial sections as the norm from an Inflationary point of view. Here we wish to argue that cosmic holography, in the novel form proposed by Maldacena and Maoz [2], gives a deep new interpretation of this idea, and also sharpens it very considerably to exclude the negative case. This focuses our attention on cosmological models with flat, compact spatial sections. Current observations [3] show that the spatial sections of our Universe [as defined by observers for whom local isotropy obtains] are fairly close to being flat: the total density parameter Ω satisfies Ω = 1.02 0.02 at 95% confidence level, if we allow the imposition ± of a reasonable prior [4] on the Hubble parameter. -
Anomalies, Dualities, and Topology of D = 6 N = 1 Superstring Vacua
RU-96-16 NSF-ITP-96-21 CALT-68-2057 IASSNS-HEP-96/53 hep-th/9605184 Anomalies, Dualities, and Topology of D =6 N =1 Superstring Vacua Micha Berkooz,1 Robert G. Leigh,1 Joseph Polchinski,2 John H. Schwarz,3 Nathan Seiberg,1 and Edward Witten4 1Department of Physics, Rutgers University, Piscataway, NJ 08855-0849 2Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030 3California Institute of Technology, Pasadena, CA 91125 4Institute for Advanced Study, Princeton, NJ 08540 Abstract We consider various aspects of compactifications of the Type I/heterotic Spin(32)/Z2 theory on K3. One family of such compactifications in- cludes the standard embedding of the spin connection in the gauge group, and is on the same moduli space as the compactification of arXiv:hep-th/9605184v1 25 May 1996 the heterotic E8 × E8 theory on K3 with instanton numbers (8,16). Another class, which includes an orbifold of the Type I theory re- cently constructed by Gimon and Polchinski and whose field theory limit involves some topological novelties, is on the moduli space of the heterotic E8 × E8 theory on K3 with instanton numbers (12,12). These connections between Spin(32)/Z2 and E8 × E8 models can be demonstrated by T duality, and permit a better understanding of non- perturbative gauge fields in the (12,12) model. In the transformation between Spin(32)/Z2 and E8 × E8 models, the strong/weak coupling duality of the (12,12) E8 × E8 model is mapped to T duality in the Type I theory. The gauge and gravitational anomalies in the Type I theory are canceled by an extension of the Green-Schwarz mechanism. -
Fabiola Gianotti
Fabiola Gianotti Date of Birth 29 October 1960 Place Rome, Italy Nomination 18 August 2020 Field Physics Title Director-General of the European Laboratory for Particle Physics, CERN, Geneva Most important awards, prizes and academies Honorary Professor, University of Edinburgh; Corresponding or foreign associate member of the Italian Academy of Sciences (Lincei), the National Academy of Sciences of the United States, the French Academy of Sciences, the Royal Society London, the Royal Academy of Sciences and Arts of Barcelona, the Royal Irish Academy and the Russian Academy of Sciences. Honorary doctoral degrees from: University of Uppsala (2012); Ecole Polytechnique Federale de Lausanne (2013); McGill University, Montreal (2014); University of Oslo (2014); University of Edinburgh (2015); University of Roma Tor Vergata (2017); University of Chicago (2018); University Federico II, Naples (2018); Université de Paris Sud, Orsay (2018); Université Savoie Mont Blanc, Annecy (2018); Weizmann Institute, Israel (2018); Imperial College, London (2019). National honours: Cavaliere di Gran Croce dell'Ordine al Merito della Repubblica, awarded by the Italian President Giorgio Napolitano (2014). Special Breakthrough Prize in Fundamental Physics (shared, 2013); Enrico Fermi Prize of the Italian Physical Society (shared, 2013); Medal of Honour of the Niels Bohr Institute, Copenhagen (2013); Wilhelm Exner Medal, Vienna (2017); Tate Medal of the American Institute of Physics for International Leadership (2019). Summary of scientific research Fabiola Gianotti is a particle physicist working at high-energy accelerators. In her scientific career, she has made significant contributions to several experiments at CERN, including UA2 at the proton-antiproton collider (SpbarpS), ALEPH at the Large Electron-Positron collider (LEP) and ATLAS at the Large Hadron Collider (LHC). -
Calorimetry for Particle Physics
REVIEWS OF MODERN PHYSICS, VOLUME 75, OCTOBER 2003 Calorimetry for particle physics Christian W. Fabjan and Fabiola Gianotti CERN, 1211 Geneva 23, Switzerland (Published 15 October 2003) Calorimetry has become a well-understood, powerful, and versatile measurement method. Besides perfecting this technique to match increasingly demanding operation at high-energy particle accelerators, physicists are developing low-temperature calorimeters to extend detection down to ever lower energies, and atmospheric and deep-sea calorimeters to scrutinize the universe up to the highest energies. The authors summarize the state of the art, with emphasis on the physics of the detectors and innovative technologies. CONTENTS VI. Citius, Altius, Fortius 1280 A. Introduction 1280 B. Atmospheric calorimeters 1280 I. Introduction 1243 1. Setting the energy scale 1283 II. Electromagnetic Calorimetry 1244 2. Energy resolution 1283 A. Physics of the electromagnetic cascade 1244 C. Deep-water calorimeters 1283 B. Energy resolution of electromagnetic VII. Conclusions 1284 calorimeters 1246 Acknowledgments 1284 1. Stochastic term 1247 References 1284 2. Noise term 1247 3. Constant term 1247 4. Additional contributions 1248 C. Main techniques and examples of facilities 1249 I. INTRODUCTION 1. Homogeneous calorimeters 1249 a. Semiconductor calorimeters 1249 Calorimetry is an ubiquitous detection principle in b. Cherenkov calorimeters 1250 particle physics. Originally invented for the study of c. Scintillation calorimeters 1251 cosmic-ray phenomena, this method was developed and d. Noble-liquid calorimeters 1254 perfected for accelerator-based particle physics experi- 2. Sampling calorimeters 1256 mentation primarily in order to measure the energy of a. Scintillation sampling calorimeters 1257 electrons, photons, and hadrons. Calorimeters are b. Gas sampling calorimeters 1257 blocks of instrumented material in which particles to be c. -
Some Comments on Physical Mathematics
Preprint typeset in JHEP style - HYPER VERSION Some Comments on Physical Mathematics Gregory W. Moore Abstract: These are some thoughts that accompany a talk delivered at the APS Savannah meeting, April 5, 2014. I have serious doubts about whether I deserve to be awarded the 2014 Heineman Prize. Nevertheless, I thank the APS and the selection committee for their recognition of the work I have been involved in, as well as the Heineman Foundation for its continued support of Mathematical Physics. Above all, I thank my many excellent collaborators and teachers for making possible my participation in some very rewarding scientific research. 1 I have been asked to give a talk in this prize session, and so I will use the occasion to say a few words about Mathematical Physics, and its relation to the sub-discipline of Physical Mathematics. I will also comment on how some of the work mentioned in the citation illuminates this emergent field. I will begin by framing the remarks in a much broader historical and philosophical context. I hasten to add that I am neither a historian nor a philosopher of science, as will become immediately obvious to any expert, but my impression is that if we look back to the modern era of science then major figures such as Galileo, Kepler, Leibniz, and New- ton were neither physicists nor mathematicans. Rather they were Natural Philosophers. Even around the turn of the 19th century the same could still be said of Bernoulli, Euler, Lagrange, and Hamilton. But a real divide between Mathematics and Physics began to open up in the 19th century. -
2005 March Meeting Gears up for Showtime in the City of Angels
NEWS See Pullout Insert Inside March 2005 Volume 14, No. 3 A Publication of The American Physical Society http://www.aps.org/apsnews 2005 March Meeting Gears Up for Reborn Nicholson Medal Showtime in the City of Angels Stresses Mentorship Established in memory of Dwight The latest research relevance to the design R. Nicholson of the University of results on the spin Hall and creation of next- Iowa, who died tragically in 1991, effect, new chemistry generation nano-electro- and first given in 1994, the APS with superatoms, and mechanical systems Nicholson Medal has been reborn several sessions cel- (NEMS). Moses Chan this year as an award for human ebrating all things (Pennsylvania State Uni- outreach. According to the infor- Einstein are among the versity) will talk about mation contained on the Medal’s expected highlights at evidence of Bose-Einstein web site (http://www.aps.org/praw/ the 2005 APS March condensation in solid he- nicholso/index.cfm), the Nicholson meeting, to be held later lium, while Stanford Medal for Human Outreach shall Photo Credit: Courtesy of the Los Angeles Convention Center this month in Los University’s Zhixun Shen be awarded to a physicist who ei- Angeles, California. The will discuss how photo- ther through teaching, research, or Photo from Iowa University Relations. conference is the largest physics Boltzmann, and Ehrenfest, but also emission spectroscopy has science-related activities, Dwight R. Nicholson. meeting of the year, featuring some Emmy Noether, one of the rare emerged as a leading tool to push -
Round Table Talk: Conversation with Nathan Seiberg
Round Table Talk: Conversation with Nathan Seiberg Nathan Seiberg Professor, the School of Natural Sciences, The Institute for Advanced Study Hirosi Ooguri Kavli IPMU Principal Investigator Yuji Tachikawa Kavli IPMU Professor Ooguri: Over the past few decades, there have been remarkable developments in quantum eld theory and string theory, and you have made signicant contributions to them. There are many ideas and techniques that have been named Hirosi Ooguri Nathan Seiberg Yuji Tachikawa after you, such as the Seiberg duality in 4d N=1 theories, the two of you, the Director, the rest of about supersymmetry. You started Seiberg-Witten solutions to 4d N=2 the faculty and postdocs, and the to work on supersymmetry almost theories, the Seiberg-Witten map administrative staff have gone out immediately or maybe a year after of noncommutative gauge theories, of their way to help me and to make you went to the Institute, is that right? the Seiberg bound in the Liouville the visit successful and productive – Seiberg: Almost immediately. I theory, the Moore-Seiberg equations it is quite amazing. I don’t remember remember studying supersymmetry in conformal eld theory, the Afeck- being treated like this, so I’m very during the 1982/83 Christmas break. Dine-Seiberg superpotential, the thankful and embarrassed. Ooguri: So, you changed the direction Intriligator-Seiberg-Shih metastable Ooguri: Thank you for your kind of your research completely after supersymmetry breaking, and many words. arriving the Institute. I understand more. Each one of them has marked You received your Ph.D. at the that, at the Weizmann, you were important steps in our progress. -
David Olive: His Life and Work
David Olive his life and work Edward Corrigan Department of Mathematics, University of York, YO10 5DD, UK Peter Goddard Institute for Advanced Study, Princeton, NJ 08540, USA St John's College, Cambridge, CB2 1TP, UK Abstract David Olive, who died in Barton, Cambridgeshire, on 7 November 2012, aged 75, was a theoretical physicist who made seminal contributions to the development of string theory and to our understanding of the structure of quantum field theory. In early work on S-matrix theory, he helped to provide the conceptual framework within which string theory was initially formulated. His work, with Gliozzi and Scherk, on supersymmetry in string theory made possible the whole idea of superstrings, now understood as the natural framework for string theory. Olive's pioneering insights about the duality between electric and magnetic objects in gauge theories were way ahead of their time; it took two decades before his bold and courageous duality conjectures began to be understood. Although somewhat quiet and reserved, he took delight in the company of others, generously sharing his emerging understanding of new ideas with students and colleagues. He was widely influential, not only through the depth and vision of his original work, but also because the clarity, simplicity and elegance of his expositions of new and difficult ideas and theories provided routes into emerging areas of research, both for students and for the theoretical physics community more generally. arXiv:2009.05849v1 [physics.hist-ph] 12 Sep 2020 [A version of section I Biography is to be published in the Biographical Memoirs of Fellows of the Royal Society.] I Biography Childhood David Olive was born on 16 April, 1937, somewhat prematurely, in a nursing home in Staines, near the family home in Scotts Avenue, Sunbury-on-Thames, Surrey. -
Is String Theory Holographic? 1 Introduction
Holography and large-N Dualities Is String Theory Holographic? Lukas Hahn 1 Introduction1 2 Classical Strings and Black Holes2 3 The Strominger-Vafa Construction3 3.1 AdS/CFT for the D1/D5 System......................3 3.2 The Instanton Moduli Space.........................6 3.3 The Elliptic Genus.............................. 10 1 Introduction The holographic principle [1] is based on the idea that there is a limit on information content of spacetime regions. For a given volume V bounded by an area A, the state of maximal entropy corresponds to the largest black hole that can fit inside V . This entropy bound is specified by the Bekenstein-Hawking entropy A S ≤ S = (1.1) BH 4G and the goings-on in the relevant spacetime region are encoded on "holographic screens". The aim of these notes is to discuss one of the many aspects of the question in the title, namely: "Is this feature of the holographic principle realized in string theory (and if so, how)?". In order to adress this question we start with an heuristic account of how string like objects are related to black holes and how to compare their entropies. This second section is exclusively based on [2] and will lead to a key insight, the need to consider BPS states, which allows for a more precise treatment. The most fully understood example is 1 a bound state of D-branes that appeared in the original article on the topic [3]. The third section is an attempt to review this construction from a point of view that highlights the role of AdS/CFT [4,5]. -
Language and Materiality Ethnographic and Theoretical Explorations
Language and Materiality Ethnographic and Theoretical Explorations Edited by Jillian R. Cavanaugh CUNY, New York Shalini Shankar Northwestern University University Printing House, Cambridge CB2 8BS, United Kingdom One Liberty Plaza, 20th Floor, New York, NY 10006, USA 477 Williamstown Road, Port Melbourne, VIC 3207, Australia 4843/24, 2nd Floor, Ansari Road, Daryaganj, Delhi - 110002, India 79 Anson Road, #06-04/06, Singapore 079906 Cambridge University Press is part of the University of Cambridge. It furthers the University’s mission by disseminating knowledge in the pursuit of education, learning, and research at the highest international levels of excellence. www.cambridge.org Information on this title: www.cambridge.org/9781107180949 DOI: 10.1017/9781316848418 C Cambridge University Press 2017 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2017 Printed in <country> by <printer> A catalogue record for this publication is available from the British Library. Library of Congress Cataloging-in-Publication Data ISBN 978-1-107-18094-9 Hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. 4 Fontroversy! Or, How to Care about the Shape of Language Keith M. Murphy Introduction On July 4, 2012, standing in the well of a packed lecture hall on the cam- pus of the European Organization for Nuclear Research (CERN), just outside Geneva, particle physicist Joseph Incandela looked up at the hall’s projection screen and, with only a hint of nerves in his voice, uttered the following pro- nouncement: “If we combine the ZZ and gamma-gamma, this is what we get. -
Thoughts About Quantum Field Theory Nathan Seiberg IAS
Thoughts About Quantum Field Theory Nathan Seiberg IAS Thank Edward Witten for many relevant discussions QFT is the language of physics It is everywhere • Particle physics: the language of the Standard Model • Enormous success, e.g. the electron magnetic dipole moment is theoretically 1.001 159 652 18 … experimentally 1.001 159 652 180... • Condensed matter • Description of the long distance properties of materials: phases and the transitions between them • Cosmology • Early Universe, inflation • … QFT is the language of physics It is everywhere • String theory/quantum gravity • On the string world-sheet • In the low-energy approximation (spacetime) • The whole theory (gauge/gravity duality) • Applications in mathematics especially in geometry and topology • Quantum field theory is the modern calculus • Natural language for describing diverse phenomena • Enormous progress over the past decades, still continuing 2011 Solvay meeting Comments on QFT 5 minutes, only one slide Should quantum field theory be reformulated? • Should we base the theory on a Lagrangian? • Examples with no semi-classical limit – no Lagrangian • Examples with several semi-classical limits – several Lagrangians • Many exact solutions of QFT do not rely on a Lagrangian formulation • Magic in amplitudes – beyond Feynman diagrams • Not mathematically rigorous • Extensions of traditional local QFT 5 How should we organize QFTs? QFT in High Energy Theory Start at high energies with a scale invariant theory, e.g. a free theory described by Lagrangian. Λ Deform it with • a finite set of coefficients of relevant (or marginally relevant) operators, e.g. masses • a finite set of coefficients of exactly marginal operators, e.g. in 4d = 4. -
Prhep Hep2001
International Europhysics Conference on HEP PROCEEDINGS Searches for new particles at Colliders Fabiola Gianotti∗ CERN, EP Division, 1211 Gen`eve 23, Switzerland E-mail: [email protected] Abstract: Most recent results from the searches for new particles at LEP, Tevatron and PrHEP hep2001 HERA, presented at the 2001 Summer Conferences, are reviewed. Prospects at future machines (LHC and Linear Colliders) are also discussed. The emphasis is put on the quest for Higgs bosons, Supersymmetry, Extra-dimensions and Flavour-Changing Neu- tral Current processes. In each case, the phenomenological framework, the experimental strategies, and the analysis methods are described, and the sensitivity and reach of the various machines are compared. 1. Introduction The search for new particles is one of the most exciting, rapidly-evolving and prolific fields in today’s high-energy experimental physics, motivated also by a rich spectrum of theoretical scenarios and predictions. Over the last years, the three operational high-energy Colliders, LEP, Tevatron and HERA, have explored the few hundred GeV energy range and set stringent bounds on various models. In addition, recently LEP has reported an exciting 2σ hint in the search for a Standard Model (SM) Higgs boson of mass about 115 GeV, and the H1 experiment at HERA has observed an excess of W ’s produced in association with a high transverse momentum hadronic system. Since 1996, i.e. since the beginning of its phase two, LEP has delivered an integrated 1 luminosity of about 700 pb− per experiment at a centre-of-mass energy above the W -pair production threshold. The machine performance in terms of both energy and luminosity went beyond any optimistic expectation.