The Scientific Contributions of Jo¨El Scherk
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Particles-Versus-Strings.Pdf
Particles vs. strings http://insti.physics.sunysb.edu/~siegel/vs.html In light of the huge amount of propaganda and confusion regarding string theory, it might be useful to consider the relative merits of the descriptions of the fundamental constituents of matter as particles or strings. (More-skeptical reviews can be found in my physics parodies.A more technical analysis can be found at "Warren Siegel's research".) Predictability The main problem in high energy theoretical physics today is predictions, especially for quantum gravity and confinement. An important part of predictability is calculability. There are various levels of calculations possible: 1. Existence: proofs of theorems, answers to yes/no questions 2. Qualitative: "hand-waving" results, answers to multiple choice questions 3. Order of magnitude: dimensional analysis arguments, 10? (but beware hidden numbers, like powers of 4π) 4. Constants: generally low-energy results, like ground-state energies 5. Functions: complete results, like scattering probabilities in terms of energy and angle Any but the last level eventually leads to rejection of the theory, although previous levels are acceptable at early stages, as long as progress is encouraging. It is easy to write down the most general theory consistent with special (and for gravity, general) relativity, quantum mechanics, and field theory, but it is too general: The spectrum of particles must be specified, and more coupling constants and varieties of interaction become available as energy increases. The solutions to this problem go by various names -- "unification", "renormalizability", "finiteness", "universality", etc. -- but they are all just different ways to realize the same goal of predictability. -
Supergravity and Its Legacy Prelude and the Play
Supergravity and its Legacy Prelude and the Play Sergio FERRARA (CERN – LNF INFN) Celebrating Supegravity at 40 CERN, June 24 2016 S. Ferrara - CERN, 2016 1 Supergravity as carved on the Iconic Wall at the «Simons Center for Geometry and Physics», Stony Brook S. Ferrara - CERN, 2016 2 Prelude S. Ferrara - CERN, 2016 3 In the early 1970s I was a staff member at the Frascati National Laboratories of CNEN (then the National Nuclear Energy Agency), and with my colleagues Aurelio Grillo and Giorgio Parisi we were investigating, under the leadership of Raoul Gatto (later Professor at the University of Geneva) the consequences of the application of “Conformal Invariance” to Quantum Field Theory (QFT), stimulated by the ongoing Experiments at SLAC where an unexpected Bjorken Scaling was observed in inclusive electron- proton Cross sections, which was suggesting a larger space-time symmetry in processes dominated by short distance physics. In parallel with Alexander Polyakov, at the time in the Soviet Union, we formulated in those days Conformal invariant Operator Product Expansions (OPE) and proposed the “Conformal Bootstrap” as a non-perturbative approach to QFT. S. Ferrara - CERN, 2016 4 Conformal Invariance, OPEs and Conformal Bootstrap has become again a fashionable subject in recent times, because of the introduction of efficient new methods to solve the “Bootstrap Equations” (Riccardo Rattazzi, Slava Rychkov, Erik Tonni, Alessandro Vichi), and mostly because of their role in the AdS/CFT correspondence. The latter, pioneered by Juan Maldacena, Edward Witten, Steve Gubser, Igor Klebanov and Polyakov, can be regarded, to some extent, as one of the great legacies of higher dimensional Supergravity. -
Subnuclear Physics: Past, Present and Future
Subnuclear Physics: Past, Present and Future International Symposium 30 October - 2 November 2011 – The purpose of the Symposium is to discuss the origin, the status and the future of the new frontier of Physics, the Subnuclear World, whose first two hints were discovered in the middle of the last century: the so-called “Strange Particles” and the “Resonance #++”. It took more than two decades to understand the real meaning of these two great discoveries: the existence of the Subnuclear World with regularities, spontaneously plus directly broken Symmetries, and totally unexpected phenomena including the existence of a new fundamental force of Nature, called Quantum ChromoDynamics. In order to reach this new frontier of our knowledge, new Laboratories were established all over the world, in Europe, in USA and in the former Soviet Union, with thousands of physicists, engineers and specialists in the most advanced technologies, engaged in the implementation of new experiments of ever increasing complexity. At present the most advanced Laboratory in the world is CERN where experiments are being performed with the Large Hadron Collider (LHC), the most powerful collider in the world, which is able to reach the highest energies possible in this satellite of the Sun, called Earth. Understanding the laws governing the Space-time intervals in the range of 10-17 cm and 10-23 sec will allow our form of living matter endowed with Reason to open new horizons in our knowledge. Antonino Zichichi Participants Prof. Werner Arber H.E. Msgr. Marcelo Sánchez Sorondo Prof. Guido Altarelli Prof. Ignatios Antoniadis Prof. Robert Aymar Prof. Rinaldo Baldini Ferroli Prof. -
Field Theory Insight from the Ads/CFT Correspondence
Field theory insight from the AdS/CFT correspondence Daniel Z.Freedman1 and Pierre Henry-Labord`ere2 1Department of Mathematics and Center for Theoretical Physics Massachusetts Institute of Technology, Cambridge, MA 01239 E-mail: [email protected] 2LPT-ENS, 24, rue Lhomond F-75231 Paris cedex 05, France E-mail: [email protected] ABSTRACT A survey of ideas, techniques and results from d=5 supergravity for the conformal and mass-perturbed phases of d=4 N =4 Super-Yang-Mills theory. arXiv:hep-th/0011086v2 29 Nov 2000 1 Introduction The AdS/CF T correspondence [1, 20, 11, 12] allows one to calculate quantities of interest in certain d=4 supersymmetric gauge theories using 5 and 10-dimensional supergravity. Mirac- ulously one gets information on a strong coupling limit of the gauge theory– information not otherwise available– from classical supergravity in which calculations are feasible. The prime example of AdS/CF T is the duality between =4 SYM theory and D=10 N Type IIB supergravity. The field theory has the very special property that it is ultraviolet finite and thus conformal invariant. Many years of elegant work on 2-dimensional CF T ′s has taught us that it is useful to consider both the conformal theory and its deformation by relevant operators which changes the long distance behavior and generates a renormalization group flow of the couplings. Analogously, in d=4, one can consider a) the conformal phase of =4 SYM N b) the same theory deformed by adding mass terms to its Lagrangian c) the Coulomb/Higgs phase. -
Graphs and Patterns in Mathematics and Theoretical Physics, Volume 73
http://dx.doi.org/10.1090/pspum/073 Graphs and Patterns in Mathematics and Theoretical Physics This page intentionally left blank Proceedings of Symposia in PURE MATHEMATICS Volume 73 Graphs and Patterns in Mathematics and Theoretical Physics Proceedings of the Conference on Graphs and Patterns in Mathematics and Theoretical Physics Dedicated to Dennis Sullivan's 60th birthday June 14-21, 2001 Stony Brook University, Stony Brook, New York Mikhail Lyubich Leon Takhtajan Editors Proceedings of the conference on Graphs and Patterns in Mathematics and Theoretical Physics held at Stony Brook University, Stony Brook, New York, June 14-21, 2001. 2000 Mathematics Subject Classification. Primary 81Txx, 57-XX 18-XX 53Dxx 55-XX 37-XX 17Bxx. Library of Congress Cataloging-in-Publication Data Stony Brook Conference on Graphs and Patterns in Mathematics and Theoretical Physics (2001 : Stony Brook University) Graphs and Patterns in mathematics and theoretical physics : proceedings of the Stony Brook Conference on Graphs and Patterns in Mathematics and Theoretical Physics, June 14-21, 2001, Stony Brook University, Stony Brook, NY / Mikhail Lyubich, Leon Takhtajan, editors. p. cm. — (Proceedings of symposia in pure mathematics ; v. 73) Includes bibliographical references. ISBN 0-8218-3666-8 (alk. paper) 1. Graph Theory. 2. Mathematics-Graphic methods. 3. Physics-Graphic methods. 4. Man• ifolds (Mathematics). I. Lyubich, Mikhail, 1959- II. Takhtadzhyan, L. A. (Leon Armenovich) III. Title. IV. Series. QA166.S79 2001 511/.5-dc22 2004062363 Copying and reprinting. Material in this book may be reproduced by any means for edu• cational and scientific purposes without fee or permission with the exception of reproduction by services that collect fees for delivery of documents and provided that the customary acknowledg• ment of the source is given. -
Twenty Years of the Weyl Anomaly
CTP-TAMU-06/93 Twenty Years of the Weyl Anomaly † M. J. Duff ‡ Center for Theoretical Physics Physics Department Texas A & M University College Station, Texas 77843 ABSTRACT In 1973 two Salam prot´eg´es (Derek Capper and the author) discovered that the conformal invariance under Weyl rescalings of the metric tensor 2 gµν(x) Ω (x)gµν (x) displayed by classical massless field systems in interac- tion with→ gravity no longer survives in the quantum theory. Since then these Weyl anomalies have found a variety of applications in black hole physics, cosmology, string theory and statistical mechanics. We give a nostalgic re- view. arXiv:hep-th/9308075v1 16 Aug 1993 CTP/TAMU-06/93 July 1993 †Talk given at the Salamfest, ICTP, Trieste, March 1993. ‡ Research supported in part by NSF Grant PHY-9106593. When all else fails, you can always tell the truth. Abdus Salam 1 Trieste and Oxford Twenty years ago, Derek Capper and I had embarked on our very first post- docs here in Trieste. We were two Salam students fresh from Imperial College filled with ideas about quantizing the gravitational field: a subject which at the time was pursued only by mad dogs and Englishmen. (My thesis title: Problems in the Classical and Quantum Theories of Gravitation was greeted with hoots of derision when I announced it at the Cargese Summer School en route to Trieste. The work originated with a bet between Abdus Salam and Hermann Bondi about whether you could generate the Schwarzschild solution using Feynman diagrams. You can (and I did) but I never found out if Bondi ever paid up.) Inspired by Salam, Capper and I decided to use the recently discovered dimensional regularization1 to calculate corrections to the graviton propaga- tor from closed loops of massless particles: vectors [1] and spinors [2], the former in collaboration with Leopold Halpern. -
Supergravity at 40: Reflections and Perspectives(∗)
RIVISTA DEL NUOVO CIMENTO Vol. 40, N. 6 2017 DOI 10.1393/ncr/i2017-10136-6 ∗ Supergravity at 40: Reflections and perspectives( ) S. Ferrara(1)(2)(3)andA. Sagnotti(4) (1) Theoretical Physics Department, CERN CH - 1211 Geneva 23, Switzerland (2) INFN - Laboratori Nazionali di Frascati - Via Enrico Fermi 40 I-00044 Frascati (RM), Italy (3) Department of Physics and Astronomy, Mani L. Bhaumik Institute for Theoretical Physics U.C.L.A., Los Angeles CA 90095-1547, USA (4) Scuola Normale Superiore e INFN - Piazza dei Cavalieri 7, I-56126 Pisa, Italy received 15 February 2017 Dedicated to John H. Schwarz on the occasion of his 75th birthday Summary. — The fortieth anniversary of the original construction of Supergravity provides an opportunity to combine some reminiscences of its early days with an assessment of its impact on the quest for a quantum theory of gravity. 280 1. Introduction 280 2. The early times 282 3. The golden age 283 4. Supergravity and particle physics 284 5. Supergravity and string theory 286 6. Branes and M-theory 287 7. Supergravity and the AdS/CFT correspondence 288 8. Conclusions and perspectives ∗ ( ) Based in part on the talk delivered by S.F. at the “Special Session of the DISCRETE2016 Symposium and the Leopold Infeld Colloquium”, in Warsaw, on December 1 2016, and on a joint CERN Courier article. c Societ`a Italiana di Fisica 279 280 S. FERRARA and A. SAGNOTTI 1. – Introduction The year 2016 marked the fortieth anniversary of the discovery of Supergravity (SGR) [1], an extension of Einstein’s General Relativity [2] (GR) where Supersymme- try, promoted to a gauge symmetry, accompanies general coordinate transformations. -
Hep-Th/0011078V1 9 Nov 2000 1 Okspotdi Atb H ..Dp.O Nryudrgrant Under Energy of Dept
CALT-68-2300 CITUSC/00-060 hep-th/0011078 String Theory Origins of Supersymmetry1 John H. Schwarz California Institute of Technology, Pasadena, CA 91125, USA and Caltech-USC Center for Theoretical Physics University of Southern California, Los Angeles, CA 90089, USA Abstract The string theory introduced in early 1971 by Ramond, Neveu, and myself has two-dimensional world-sheet supersymmetry. This theory, developed at about the same time that Golfand and Likhtman constructed the four-dimensional super-Poincar´ealgebra, motivated Wess and Zumino to construct supersymmet- ric field theories in four dimensions. Gliozzi, Scherk, and Olive conjectured the arXiv:hep-th/0011078v1 9 Nov 2000 spacetime supersymmetry of the string theory in 1976, a fact that was proved five years later by Green and myself. Presented at the Conference 30 Years of Supersymmetry 1Work supported in part by the U.S. Dept. of Energy under Grant No. DE-FG03-92-ER40701. 1 S-Matrix Theory, Duality, and the Bootstrap In the late 1960s there were two parallel trends in particle physics. On the one hand, many hadron resonances were discovered, making it quite clear that hadrons are not elementary particles. In fact, they were found, to good approximation, to lie on linear parallel Regge trajectories, which supported the notion that they are composite. Moreover, high energy scattering data displayed Regge asymptotic behavior that could be explained by the extrap- olation of the same Regge trajectories, as well as one with vacuum quantum numbers called the Pomeron. This set of developments was the focus of the S-Matrix Theory community of theorists. -
Curriculum Vitae
CURRICULUM VITAE Raman Sundrum July 26, 2019 CONTACT INFORMATION Physical Sciences Complex, University of Maryland, College Park, MD 20742 Office - (301) 405-6012 Email: [email protected] CAREER John S. Toll Chair, Director of the Maryland Center for Fundamental Physics, 2012 - present. Distinguished University Professor, University of Maryland, 2011-present. Elkins Chair, Professor of Physics, University of Maryland, 2010-2012. Alumni Centennial Chair, Johns Hopkins University, 2006- 2010. Full Professor at the Department of Physics and Astronomy, The Johns Hopkins University, 2001- 2010. Associate Professor at the Department of Physics and Astronomy, The Johns Hop- kins University, 2000- 2001. Research Associate at the Department of Physics, Stanford University, 1999- 2000. Advisor { Prof. Savas Dimopoulos. 1 Postdoctoral Fellow at the Department of Physics, Boston University. 1996- 1999. Postdoc advisor { Prof. Sekhar Chivukula. Postdoctoral Fellow in Theoretical Physics at Harvard University, 1993-1996. Post- doc advisor { Prof. Howard Georgi. Postdoctoral Fellow in Theoretical Physics at the University of California at Berke- ley, 1990-1993. Postdoc advisor { Prof. Stanley Mandelstam. EDUCATION Yale University, New-Haven, Connecticut Ph.D. in Elementary Particle Theory, May 1990 Thesis Title: `Theoretical and Phenomenological Aspects of Effective Gauge Theo- ries' Thesis advisor: Prof. Lawrence Krauss Brown University, Providence, Rhode Island Participant in the 1988 Theoretical Advanced Summer Institute University of Sydney, Australia B.Sc with First Class Honours in Mathematics and Physics, Dec. 1984 AWARDS, DISTINCTIONS J. J. Sakurai Prize in Theoretical Particle Physics, American Physical Society, 2019. Distinguished Visiting Research Chair, Perimeter Institute, 2012 - present. 2 Moore Fellow, Cal Tech, 2015. American Association for the Advancement of Science, Fellow, 2011. -
Stanley Mandelstam
I knew very early of Stanley Mandelstam I started physics as a t Prisoner of the s u Mandelstam Triangle I escaped from the Mandelstam Triangle only to be ensnared in Light-Cone Superspace A Note of Personal Gratitude 1971 NAL Visit SuperConformal Theories P. Ramond (with S. Ananth, D. Belyaev, L. Brink and S.-S. Kim) Light-Cone Superspaces N=4 Super Yang-Mills N=8 SuperConformal N=8 SuperGravity and E7(7) N=16 SuperGravity and E8(8) N=8 Light-Cone Superspace houses D=11: N=1 SuperGravity SO(9); F4/SO(9) D=4: N=8 SuperGravity SO(2)x E7(7) D=3: N=16 SuperGravity E8(8) D=2: N=16 Theory E9(9) N=4 Light-Cone Superspace habitat for D=10: N=1 Super Yang-Mills SO(8) D=4: N=4 Super Yang-Mills PSU(2,2|4) D=3: N=8 Super Conformal OSp(2,2|8) 1 i 1 ϕ (y) = 1 A (y) + i θm θn C (y) + 1θm θn θp θq $ ∂+ A¯ (y) + m n mn m n p mnpqq + ¯ ϕ (y) = +∂A (y) + √2θ θ Cmn (y) +12 θ θ θ θ $mnpq ∂ A (y) ∂ √2 √ 12 1 i 1 i m 2 m n p q m n m n p q + i+ +¯ θ χ¯m(y) + √2θ θ θ $mnpq χ (y) ϕ (y) = + A (y) + θ θ Cmn (y) + θ θ θ θ $mnpq ∂ ∂Am(y) 6 m n p q ∂ √2 12 + θ χ¯m(y) + θ θ θ $mnpq χ (y) 1 i m n 1 m n p ∂q+ + ¯ 6 ϕ (y) = A (y) + √θ θ C L(C2y) + Fθorθ maθ θ $lmnpqism∂ A (y) ∂+i m √ 2 m nmnp q12 + θ χ¯m(y) +2 θ θ θ $mnpq χ (y) 1 0 3 ∂+ 6 x± = (x x ) i √2 √ m m n p q 12 0± 3 + + θ χ¯m(y) + θ θ θ $mnpq χ (y) x± = (x x ) ∂ 6 √2 ± Light-Cone Co1ordina0 3tes: 1 0 3 x± = (x x ) ∂± = ( ∂ ∂ ) √2 ± √2 − ± 1 0 3 1 0 3 x± = (x x ) ∂± = ( ∂ ∂ ) 1 0√ 3 ± 1 1 2√2 − ±1 1 2 ∂± = ( ∂ 2∂ ) x = (x + ix ) x = (x ix ) √2 − ± √2 √2 − m m + 1 1 2 1 1 2 1 q+ , q¯+ n =1 i√2δ n ∂ x = 1(x + ix -
Strings, Boundary Fermions and Coincident D-Branes
Strings, boundary fermions and coincident D-branes Linus Wulff Department of Physics Stockholm University Thesis for the degree of Doctor of Philosophy in Theoretical Physics Department of Physics, Stockholm University Sweden c Linus Wulff, Stockholm 2007 ISBN 91-7155-371-1 pp 1-85 Printed in Sweden by Universitetsservice US-AB, Stockholm 2007 Abstract The appearance in string theory of higher-dimensional objects known as D- branes has been a source of much of the interesting developements in the subject during the past ten years. A very interesting phenomenon occurs when several of these D-branes are made to coincide: The abelian gauge theory liv- ing on each brane is enhanced to a non-abelian gauge theory living on the stack of coincident branes. This gives rise to interesting effects like the natural ap- pearance of non-commutative geometry. The theory governing the dynamics of these coincident branes is still poorly understood however and only hints of the underlying structure have been seen. This thesis focuses on an attempt to better this understanding by writing down actions for coincident branes using so-called boundary fermions, orig- inating in considerations of open strings, instead of matrices to describe the non-abelian fields. It is shown that by gauge-fixing and by suitably quantiz- ing these boundary fermions the non-abelian action that is known, the Myers action, can be reproduced. Furthermore it is shown that under natural assump- tions, unlike the Myers action, the action formulated using boundary fermions also posseses kappa-symmetry, the criterion for being the correct supersym- metric action for coincident D-branes. -
Personal Recollections of the Early Days Before and After the Birth of Supergravity
Personal recollections of the early days before and after the birth of Supergravity Peter van Nieuwenhuizen I March 29, 1976: Dan Freedman, Sergio Ferrara and I submit first paper on Supergravity to Physical Review D. I April 28: Stanley Deser and Bruno Zumino: elegant reformulation that stresses the role of torsion. I June 2, 2016 at 1:30pm: 5500 papers with Supergravity in the title have appeared, and 15000 dealing with supergravity. I Supergravity has I led to the AdS/CFT miracle, and I made breakthroughs in longstanding problems in mathematics. I Final role of supergravity? (is it a solution in search of a problem?) I 336 papers in supergravity with 126 collaborators I Now: many directions I can only observe in awe from the sidelines I will therefore tell you my early recollections and some anecdotes. I will end with a new research program that I am enthusiastic about. In 1972 I was a Joliot Curie fellow at Orsay (now the Ecole Normale) in Paris. Another postdoc (Andrew Rothery from England) showed me a little book on GR by Lawden.1 I was hooked. That year Deser gave lectures at Orsay on GR, and I went with him to Brandeis. In 1973, 't Hooft and Veltman applied their new covariant quantization methods and dimensional regularization to pure gravity, using the 't Hooft lemma (Gilkey) for 1-loop divergences and the background field formalism of Bryce DeWitt. They found that at one loop, pure gravity was finite: 1 2 2 ∆L ≈ αRµν + βR = 0 on-shell. But what about matter couplings? 1\An Introduction to Tensor Calculus and Relativity".