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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. -
Supersymmetry Breaking from a Calabi-Yau Singularity
hep-th/0505029 NSF-KITP-05-27 Supersymmetry Breaking from a Calabi-Yau Singularity D. Berenstein∗, C. P. Herzog†, P. Ouyang∗, and S. Pinansky∗ † Kavli Institute for Theoretical Physics ∗ Physics Department University of California University of California Santa Barbara, CA 93106, USA Santa Barbara, CA 93106, USA Abstract We conjecture a geometric criterion for determining whether supersymmetry is spon- taneously broken in certain string backgrounds. These backgrounds contain wrapped branes at Calabi-Yau singularites with obstructions to deformation of the complex structure. We motivate our conjecture with a particular example: the Y 2,1 quiver gauge theory corresponding to a cone over the first del Pezzo surface, dP1. This setup can be analyzed using ordinary supersymmetric field theory methods, where we find that gaugino condensation drives a deformation of the chiral ring which has no solu- tions. We expect this breaking to be a general feature of any theory of branes at a singularity with a smaller number of possible deformations than independent anomaly- arXiv:hep-th/0505029v2 7 May 2005 free fractional branes. May 2005 1 Introduction Supersymmetry and supersymmetry breaking are central ideas both in contemporary par- ticle physics and in mathematical physics. In this paper, we argue that for a large new class of D-brane models there exists a simple geometric criterion which determines whether supersymmetry breaking occurs. The models of interest are based on Calabi-Yau singularities with D-branes placed at or near the singularity. By taking a large volume limit, it is possible to decouple gravity from the theory, and ignore the Calabi-Yau geometry far from the branes. -
Prospects from Strings and Branes
Prospects from strings and branes Alexander Sevrin Vrije Universiteit Brussel and The International Solvay Institutes for Physics and Chemistry http://tena4.vub.ac.be/ Moriond 2004 Strings and branes… Moriond, March 24, 2004 1 References Not-too-technical review paper, including numerous references: Strings, Gravity and Particle Physics by Augusto Sagnotti and AS In the proceedings of 37th Rencontres de Moriond on Electroweak Interactions and Unified Theories, 2002. e-Print Archive: hep-ex/0209011 Strings and branes… Moriond, March 24, 2004 2 Contents • Dirichlet-branes • D-branes and gauge theories - Worldvolume point of view -AdS/CFT • D-branes and black holes •Cosmology • Some conclusions Strings and branes… Moriond, March 24, 2004 3 Branes Solitons: solutions of the equations of motion with a finite energy(-density) and a mass inversely proportional to the coupling constant. E.g. Scalar field in d = 1 + 1: kink. 12m3 mass = λ Other example in d = 3 + 1: magnetic monopole: 1 mass ∝ 2 gYM Strings and branes… Moriond, March 24, 2004 4 Solitons in string theory: Dirichlet branes Besides the “conventional” fields, such as e.g., gµν (x)=gνµ(x): metric = graviton Φ(x): dilaton, one has RR- potentials as well. E.g. vector potential, A µ : Fµν = ∂µAν − ∂ν Aµ, Aµ → Aµ − ∂µf, Fµν → Fµν . Couples to particles: µ S = q dτ x˙ (τ)Aµ(x(τ)). Z Strings and branes… Moriond, March 24, 2004 5 E.g. 2-form potential, A µ ν = − A ν µ : Fµνρ = ∂µAνρ + ∂ν Aρµ + ∂ρAµν , Aµν → Aµν − ∂µfν + ∂ν fµ,Fµνρ → Fµνρ. Couples to strings: µ ν S = q dτdσ x˙(τ, σ) x0(τ, σ) Aµν (x(τ, σ)). -
Ads Description of Induced Higher Spin Gauge Theories
UV Completion of Some UV Fixed Points Igor Klebanov Talk at ERG2016 Conference ICTP, Trieste September 23, 2016 Talk mostly based on • L. Fei, S. Giombi, IK, arXiv:1404.1094 • S. Giombi, IK, arXiv:1409.1937 • L. Fei, S. Giombi, IK, G. Tarnopolsky, arXiv:1411.1099 • L. Fei, S. Giombi, IK, G. Tarnopolsky, arXiv:1507.01960 • L. Fei, S. Giombi, IK, G. Tarnopolsky, arXiv:1607.05316 The Gross-Neveu Model • In 2 dimensions it has some similarities with the 4-dimensional QCD. • It is asymptotically free and exhibits dynamical mass generation. • Similar physics in the 2-d O(N) non-linear sigma model with N>2. • In dimensions slightly above 2 both the O(N) and GN models have weakly coupled UV fixed points. 2+ e expansion • The beta function and fixed-point coupling are • is the number of 2-component Majorana fermions. • Can develop 2+e expansions for operator scaling dimensions, e.g. Gracey; Kivel, Stepanenko, Vasiliev • Similar expansions in the O(N) sigma model with N>2. Brezin, Zinn-Justin 4-e expansion • The O(N) sigma model is in the same universality class as the O(N) model: • It has a weakly coupled Wilson-Fisher IR fixed point in 4-e dimensions. • Using the two e expansions, the scalar CFTs with various N may be studied in the range 2<d<4. This is an excellent practical tool for CFTs in d=3. The Gross-Neveu-Yukawa Model • The GNY model is the UV completion of the GN model in d<4 Zinn-Justin; Hasenfratz, Hasenfratz, Jansen, Kuti, Shen • IR stable fixed point in 4-e dimensions • Operator scaling dimensions • Using the two e expansions, we can study the Gross-Neveu CFTs in the range 2<d<4. -
Supersymmetric Dualities and Quantum Entanglement in Conformal Field Theory
Supersymmetric Dualities and Quantum Entanglement in Conformal Field Theory Jeongseog Lee A Dissertation Presented to the Faculty of Princeton University in Candidacy for the Degree of Doctor of Philosophy Recommended for Acceptance by the Department of Physics Adviser: Igor R. Klebanov September 2016 c Copyright by Jeongseog Lee, 2016. All rights reserved. Abstract Conformal field theory (CFT) has been under intensive study for many years. The scale invariance, which arises at the fixed points of renormalization group in rela- tivistic quantum field theory (QFT), is believed to be enhanced to the full conformal group. In this dissertation we use two tools to shed light on the behavior of certain conformal field theories, the supersymmetric localization and the quantum entangle- ment Renyi entropies. The first half of the dissertation surveys the infrared (IR) structure of the = 2 N supersymmetric quantum chromodynamics (SQCD) in three dimensions. The re- cently developed F -maximization principle shows that there are richer structures along conformal fixed points compared to those in = 1 SQCD in four dimensions. N We refer to one of the new phenomena as a \crack in the conformal window". Using the known IR dualities, we investigate it for all types of simple gauge groups. We see different decoupling behaviors of operators depending on the gauge group. We also observe that gauging some flavor symmetries modifies the behavior of the theory in the IR. The second half of the dissertation uses the R`enyi entropy to understand the CFT from another angle. At the conformal fixed points of even dimensional QFT, the entanglement entropy is known to have the log-divergent universal term depending on the geometric invariants on the entangling surface. -
Thesis in Amsterdam
UvA-DARE (Digital Academic Repository) The physics and mathematics of microstates in string theory: And a monstrous Farey tail de Lange, P. Publication date 2016 Document Version Final published version Link to publication Citation for published version (APA): de Lange, P. (2016). The physics and mathematics of microstates in string theory: And a monstrous Farey tail. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:10 Oct 2021 P a u A dissertation that delves l The Physics & d into physical and e L mathematical aspects of a Microstates Mathematics of n g string theory. In the first e part ot this book, Microstates in T microscopic porperties of h Moonshine e string theoretic black String Theory P h holes are investigated. -
The Birth of String Theory
The Birth of String Theory Edited by Andrea Cappelli INFN, Florence Elena Castellani Department of Philosophy, University of Florence Filippo Colomo INFN, Florence Paolo Di Vecchia The Niels Bohr Institute, Copenhagen and Nordita, Stockholm Contents Contributors page vii Preface xi Contents of Editors' Chapters xiv Abbreviations and acronyms xviii Photographs of contributors xxi Part I Overview 1 1 Introduction and synopsis 3 2 Rise and fall of the hadronic string Gabriele Veneziano 19 3 Gravity, unification, and the superstring John H. Schwarz 41 4 Early string theory as a challenging case study for philo- sophers Elena Castellani 71 EARLY STRING THEORY 91 Part II The prehistory: the analytic S-matrix 93 5 Introduction to Part II 95 6 Particle theory in the Sixties: from current algebra to the Veneziano amplitude Marco Ademollo 115 7 The path to the Veneziano model Hector R. Rubinstein 134 iii iv Contents 8 Two-component duality and strings Peter G.O. Freund 141 9 Note on the prehistory of string theory Murray Gell-Mann 148 Part III The Dual Resonance Model 151 10 Introduction to Part III 153 11 From the S-matrix to string theory Paolo Di Vecchia 178 12 Reminiscence on the birth of string theory Joel A. Shapiro 204 13 Personal recollections Daniele Amati 219 14 Early string theory at Fermilab and Rutgers Louis Clavelli 221 15 Dual amplitudes in higher dimensions: a personal view Claud Lovelace 227 16 Personal recollections on dual models Renato Musto 232 17 Remembering the `supergroup' collaboration Francesco Nicodemi 239 18 The `3-Reggeon vertex' Stefano Sciuto 246 Part IV The string 251 19 Introduction to Part IV 253 20 From dual models to relativistic strings Peter Goddard 270 21 The first string theory: personal recollections Leonard Susskind 301 22 The string picture of the Veneziano model Holger B. -
Pos(HRMS)078 ∗ [email protected] Speaker
Two unforgettable years with Hector PoS(HRMS)078 Gabriele Veneziano∗ Collège de France, Paris, France and Theory Division, CERN, CH-1211 Geneva 23, Switzerland E-mail: [email protected] .......................... ........................... Quarks, Strings and the Cosmos - Hector Rubinstein Memorial Symposium August 09-11, 2010 AlbaNova (Stockholm) Sweden ∗Speaker. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ Two unforgettable years Gabriele Veneziano 1. Another lucky coincidence As a high school student in Florence I had the luck of being taught by some excellent teachers: Professor Tebaldo Liverani, in particular, was the one who initiated me to loving maths and physics. His preference, he once confessed, went to the former. However, after some hesitation, mine went to the latter as I entered the local University in 1960. Three years later I had to make another choice, this time about which branch of physics to go for. I was about to be "recruited" by the local high-energy experimental group when, just in time, Professor Raoul Gatto moved from Cagliari to Florence and "rescued" me to theoretical physics. PoS(HRMS)078 At the end of 1965 I received my "Laurea" in physics defending a thesis on some applications of the group SU(6)W . Only later I learned that the W in there apparently stood for Weizmann . Working in Florence as one of Gatto’s "gattini" was very stimulating. However, having always lived at home in my family in Florence, I felt the need to enlarge my horizons, both in physics and in life in general. -
![Arxiv:0804.3210V1 [Hep-Ph] 20 Apr 2008 Nrdcint Tigter N Ag/Rvt Duality Gauge/Gravity and Theory String to Introduction ∗ † O Hs Tdnswihaesatn Olanqdadqpphysics View](https://docslib.b-cdn.net/cover/4366/arxiv-0804-3210v1-hep-ph-20-apr-2008-nrdcint-tigter-n-ag-rvt-duality-gauge-gravity-and-theory-string-to-introduction-o-hs-tdnswihaesatn-olanqdadqpphysics-view-1734366.webp)
Arxiv:0804.3210V1 [Hep-Ph] 20 Apr 2008 Nrdcint Tigter N Ag/Rvt Duality Gauge/Gravity and Theory String to Introduction ∗ † O Hs Tdnswihaesatn Olanqdadqpphysics View
Introduction to String Theory and Gauge/Gravity duality ∗ for students in QCD and QGP phenomenology Institut de Physique Th´eorique; URA 2306, unit´ede recherche associ´ee au CNRS, IPhT, CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France Robi Peschanski † String theory has been initially derived from motivations coming from strong interaction phenomenology, but its application faced deep concep- tual and practical difficulties. The strong interactions found their the- oretical fundation elsewhere, namely on QCD, the quantum gauge field theory of quarks and gluons. Recently, the Gauge/Gravity correspondence allowed to initiate a reformulation of the connection between strings and gauge field theories, avoiding some of the initial drawbacks and opening the way to new insights on the gauge theory at strong coupling and even- tually QCD. Among others, the recent applications of the Gauge/Gravity correspondence to the formation of the QGP, the quark-gluon plasma, in heavy-ion reactions seem to provide a physically interesting insight on phe- nomenological features of the reactions. In these lectures we will give a arXiv:0804.3210v1 [hep-ph] 20 Apr 2008 simplified introduction to those aspects of string theory which, at the ori- gin and in the recent developments, are connected to strong interactions, for those students which are starting to learn QCD and QGP physics from an experimental or phenomenological point of view. PACS numbers: 11.15.-q,11.25.Tq ∗ Presented at the School on QCD, Low-x Physics and Diffraction, Copanello, Calabria, Italy, July 2007. † email:[email protected] (1) 2 proceedings printed on October 25, 2018 CONTENTS Lecture I: String Theory via Strong Interactions 1. -
Green-Schwarz Anomaly Cancellation
Green-Schwarz anomaly cancellation Paolo Di Vecchia Niels Bohr Instituttet, Copenhagen and Nordita, Stockholm Collège de France, 05.03.10 Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 1 / 30 Plan of the talk 1 Introduction 2 A quick look at the abelian axial anomaly 3 Few words on forms 4 Anomaly cancellation in type IIB superstring theory 5 Anomaly cancellation in type I superstring 6 Conclusions Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 2 / 30 Introduction I The theory of general relativity for gravity was formulated by Einstein in 1915. I It is a four-dimensional theory that extends the theory of special relativity. I While special relativity is invariant under the transformations of the Lorentz group, general relativity is invariant under an arbitrary change of coordinates. I In the twenties it was proposed by Theodor Kaluza and Oskar Klein to unify electromagnetism with gravity by starting from general relativity in a five-dimensional space-time and compactify the extra-dimension on a small circle. I In this way one obtains general relativity in four dimensions, a vector gauge field satisfying the Maxwell equations and a scalar. I This idea of extra dimensions was not pursued in the years after. I In the sixties and seventies, when I started to work in the physics of the elementary particles, everybody was strictly working in four dimensions. Paolo Di Vecchia (NBI+NO) GS anomaly cancellation Collège de France, 05.03.10 3 / 30 I Also the dual resonance model, being a model for hadrons, was obviously formulated in four dimensions. -
Gravity, Gauge Theory and Strings
Les Houches - Ecole d'Ete de Physique Theorique 76 Unity from Duality: Gravity, Gauge Theory and Strings Les Houches Session LXXVI, July 30 - August 31, 2001 Bearbeitet von Constantin P. Bachas, Adel Bilal, Michael R. Douglas, Nikita A. Nekrasov, Francois David 1. Auflage 2003. Buch. xxxiv, 664 S. Hardcover ISBN 978 3 540 00276 5 Format (B x L): 15,5 x 23,5 cm Gewicht: 1220 g Weitere Fachgebiete > Technik > Verfahrenstechnik, Chemieingenieurwesen, Lebensmitteltechnik Zu Inhaltsverzeichnis schnell und portofrei erhältlich bei Die Online-Fachbuchhandlung beck-shop.de ist spezialisiert auf Fachbücher, insbesondere Recht, Steuern und Wirtschaft. Im Sortiment finden Sie alle Medien (Bücher, Zeitschriften, CDs, eBooks, etc.) aller Verlage. Ergänzt wird das Programm durch Services wie Neuerscheinungsdienst oder Zusammenstellungen von Büchern zu Sonderpreisen. Der Shop führt mehr als 8 Millionen Produkte. Preface The 76th session of the Les Houches Summer School in Theoretical Physics was devoted to recent developments in string theory, gauge theories and quantum gravity. As frequently stated, Superstring Theory is the leading candidate for a unified theory of all fundamental physical forces and elementary parti- cles. This claim, and the wish to reconcile general relativity and quantum mechanics, have provided the main impetus for the development of the the- ory over the past two decades. More recently the discovery of dualities, and of important new tools such as D-branes, has greatly reinforced this point of view. On the one hand there is now good reason to believe that the underlying theory is unique. On the other hand, we have for the first time working (though unrealistic) microscopic models of black hole mechan- ics. -
Anomaly-Free Supergravities in Six Dimensions
Anomaly-Free Supergravities in Six Dimensions Ph.D. Thesis arXiv:hep-th/0611133v1 12 Nov 2006 Spyros D. Avramis National Technical University of Athens School of Applied Mathematics and Natural Sciences Department of Physics Spyros D. Avramis Anomaly-Free Supergravities in Six Dimensions Dissertation submitted to the Department of Physics of the National Technical University of Athens in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics. Thesis Advisor: Alex Kehagias Thesis Committee: Alex Kehagias Elias Kiritsis George Zoupanos K. Anagnostopoulos A.B. Lahanas E. Papantonopoulos N.D. Tracas Athens, February 2006 Abstract This thesis reviews minimal N = 2 chiral supergravities coupled to matter in six dimensions with emphasis on anomaly cancellation. In general, six-dimensional chiral supergravities suffer from gravitational, gauge and mixed anomalies which, being associated with the breakdown of local gauge symmetries, render the theories inconsistent at the quantum level. Consistency of the theory is restored if the anomalies of the theory cancel via the Green-Schwarz mechanism or generalizations thereof, in a similar manner as in the case of ten-dimensional N = 1 supergravi- ties. The anomaly cancellation conditions translate into a certain set of constraints for the gauge group of the theory as well as on its matter content. For the case of ungauged theories these constraints admit numerous solutions but, in the case of gauged theories, the allowed solutions are remarkably few. In this thesis, we examine these anomaly cancellation conditions in detail and we present all solutions to these conditions under certain restrictions on the allowed gauge groups and representations, imposed for practical reasons.