Time, E8, and the Standard Model
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The Unitary Representations of the Poincaré Group in Any Spacetime
The unitary representations of the Poincar´e group in any spacetime dimension Xavier Bekaert a and Nicolas Boulanger b a Institut Denis Poisson, Unit´emixte de Recherche 7013, Universit´ede Tours, Universit´ed’Orl´eans, CNRS, Parc de Grandmont, 37200 Tours (France) [email protected] b Service de Physique de l’Univers, Champs et Gravitation Universit´ede Mons – UMONS, Place du Parc 20, 7000 Mons (Belgium) [email protected] An extensive group-theoretical treatment of linear relativistic field equa- tions on Minkowski spacetime of arbitrary dimension D > 2 is presented in these lecture notes. To start with, the one-to-one correspondence be- tween linear relativistic field equations and unitary representations of the isometry group is reviewed. In turn, the method of induced representa- tions reduces the problem of classifying the representations of the Poincar´e group ISO(D 1, 1) to the classification of the representations of the sta- − bility subgroups only. Therefore, an exhaustive treatment of the two most important classes of unitary irreducible representations, corresponding to massive and massless particles (the latter class decomposing in turn into the “helicity” and the “infinite-spin” representations) may be performed via the well-known representation theory of the orthogonal groups O(n) (with D 4 <n<D ). Finally, covariant field equations are given for each − unitary irreducible representation of the Poincar´egroup with non-negative arXiv:hep-th/0611263v2 13 Jun 2021 mass-squared. Tachyonic representations are also examined. All these steps are covered in many details and with examples. The present notes also include a self-contained review of the representation theory of the general linear and (in)homogeneous orthogonal groups in terms of Young diagrams. -
S-Duality, the 4D Superconformal Index and 2D Topological QFT
Review of superconformal index = 2 : A generalized quivers = 2: A generalized quivers = 4 index = 1 N 1 N 2 N N S-duality, the 4d Superconformal Index and 2d Topological QFT Leonardo Rastelli with A. Gadde, E. Pomoni, S. Razamat and W. Yan arXiv:0910.2225,arXiv:1003.4244, and in progress Yang Institute for Theoretical Physics, Stony Brook Rutgers, November 9 2010 Review of superconformal index = 2 : A generalized quivers = 2: A generalized quivers = 4 index = 1 N 1 N 2 N N A new paradigm for 4d =2 susy gauge theories N (Gaiotto, . ) Compactification of the (2, 0) 6d theory on a 2d surface Σ, with punctures. = =2 superconformal⇒ theories in four dimensions. N Review of superconformal index = 2 : A generalized quivers = 2: A generalized quivers = 4 index = 1 N 1 N 2 N N A new paradigm for 4d =2 susy gauge theories N (Gaiotto, . ) Compactification of the (2, 0) 6d theory on a 2d surface Σ, with punctures. = =2 superconformal⇒ theories in four dimensions. N Space of complex structures Σ = parameter space of the 4d • theory. Moore-Seiberg groupoid of Σ = (generalized) 4d S-duality • Vast generalization of “ =4 S-duality as modular group of T 2”. N Review of superconformal index = 2 : A generalized quivers = 2: A generalized quivers = 4 index = 1 N 1 N 2 N N A new paradigm for 4d =2 susy gauge theories N (Gaiotto, . ) Compactification of the (2, 0) 6d theory on a 2d surface Σ, with punctures. = =2 superconformal⇒ theories in four dimensions. N Space of complex structures Σ = parameter space of the 4d • theory. -
The Top Yukawa Coupling from 10D Supergravity with E8 × E8 Matter
hep-th/9804107 ITEP-98-11 The top Yukawa coupling from 10D supergravity with E E matter 8 × 8 K.Zyablyuk1 Institute of Theoretical and Experimental Physics, Moscow Abstract We consider the compactification of N=1, D=10 supergravity with E E Yang- 8 × 8 Mills matter to N=1, D=4 model with 3 generations. With help of embedding SU(5) → SO(10) E E we find the value of the top Yukawa coupling λ = 16πα =3 → 6 → 8 t GUT at the GUT scale. p 1 Introduction Although superstring theories have great success and today are the best candidates for a quantum theory unifying all interactions, they still do not predict any experimentally testable value, mostly because there is no unambiguous procedure of compactification of extra spatial dimensions. On the other hand, many phenomenological models based on the unification group SO(10) were constructed (for instance [1]). They describe quarks and leptons in representa- tions 161,162,163 and Higgses, responsible for SU(2) breaking, in 10. Basic assumption of these models is that there is only one Yukawa coupling 163 10 163 at the GUT scale, which gives masses of third generation. Masses of first two families· and· mixings are generated due to the interaction with additional superheavy ( MGUT ) states in 16 + 16, 45, 54. Such models explain generation mass hierarchy and allow∼ to express all Yukawa matrices, which well fit into experimentally observable pattern, in terms of few unknown parameters. Models of [1] are unlikely derivable from ”more fundamental” theory like supergrav- ity/string. Nevertheless, something similar can be constructed from D=10 supergravity coupled to E8 E8 matter, which is low-energy limit of heterotic string [2]. -
N = 2 Dualities and 2D TQFT Space of Complex Structures Σ = Parameter Space of the 4D Theory
Short review of superconformal index 2d TQFT and orthogonal polynomials Results and Applications = 2 Dualities and 2d TQFT N Abhijit Gadde with L. Rastelli, S. Razamat and W. Yan arXiv:0910.2225 arXiv:1003.4244 arXiv:1104.3850 arXiv:1110:3740 ... California Institute of Technology Indian Israeli String Meeting 2012 Abhijit Gadde N = 2 Dualities and 2d TQFT Space of complex structures Σ = parameter space of the 4d theory. Mapping class group of Σ = (generalized) 4d S-duality Punctures: SU(2) ! SU(N) = Flavor symmetry: Commutant We will focus on "maximal" puncture: with SU(N) flavor symmetry Sphere with 3 punctures = Theories without parameters Free hypermultiplets Strongly coupled fixed points Vast generalization of “N = 4 S-duality as modular group of T 2”. 6=4+2: beautiful and unexpected 4d/2d connections. For ex., Correlators of Liouville/Toda on Σ compute the 4d partition functions (on S4) Short review of superconformal index 2d TQFT and orthogonal polynomials Results and Applications A new paradigm for 4d = 2 SCFTs [Gaiotto, . ] N Compactify of the 6d (2; 0) AN−1 theory on a 2d surface Σ, with punctures. =)N = 2 superconformal theories in four dimensions. Abhijit Gadde N = 2 Dualities and 2d TQFT We will focus on "maximal" puncture: with SU(N) flavor symmetry Sphere with 3 punctures = Theories without parameters Free hypermultiplets Strongly coupled fixed points Vast generalization of “N = 4 S-duality as modular group of T 2”. 6=4+2: beautiful and unexpected 4d/2d connections. For ex., Correlators of Liouville/Toda on Σ compute the 4d partition functions (on S4) Short review of superconformal index 2d TQFT and orthogonal polynomials Results and Applications A new paradigm for 4d = 2 SCFTs [Gaiotto, . -
Classification of Holomorphic Framed Vertex Operator Algebras of Central Charge 24
Classification of holomorphic framed vertex operator algebras of central charge 24 Ching Hung Lam, Hiroki Shimakura American Journal of Mathematics, Volume 137, Number 1, February 2015, pp. 111-137 (Article) Published by Johns Hopkins University Press DOI: https://doi.org/10.1353/ajm.2015.0001 For additional information about this article https://muse.jhu.edu/article/570114/summary Access provided by Tsinghua University Library (22 Nov 2018 10:39 GMT) CLASSIFICATION OF HOLOMORPHIC FRAMED VERTEX OPERATOR ALGEBRAS OF CENTRAL CHARGE 24 By CHING HUNG LAM and HIROKI SHIMAKURA Abstract. This article is a continuation of our work on the classification of holomorphic framed vertex operator algebras of central charge 24. We show that a holomorphic framed VOA of central charge 24 is uniquely determined by the Lie algebra structure of its weight one subspace. As a consequence, we completely classify all holomorphic framed vertex operator algebras of central charge 24 and show that there exist exactly 56 such vertex operator algebras, up to isomorphism. 1. Introduction. The classification of holomorphic vertex operator alge- bras (VOAs) of central charge 24 is one of the fundamental problems in vertex operator algebras and mathematical physics. In 1993 Schellekens [Sc93] obtained a partial classification by determining possible Lie algebra structures for the weight one subspaces of holomorphic VOAs of central charge 24. There are 71 cases in his list but only 39 of the 71 cases were known explicitly at that time. It is also an open question if the Lie algebra structure of the weight one subspace will determine the VOA structure uniquely when the central charge is 24. -
Supersymmetric Nonlinear Sigma Models
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server OU-HET 348 TIT/HET-448 hep-th/0006025 June 2000 Supersymmetric Nonlinear Sigma Models a b Kiyoshi Higashijima ∗ and Muneto Nitta † aDepartment of Physics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan bDepartment of Physics, Tokyo Institute of Technology, Oh-okayama, Meguro, Tokyo 152-8551, Japan Abstract Supersymmetric nonlinear sigma models are formulated as gauge theo- ries. Auxiliary chiral superfields are introduced to impose supersymmetric constraints of F-type. Target manifolds defined by F-type constraints are al- ways non-compact. In order to obtain nonlinear sigma models on compact manifolds, we have to introduce gauge symmetry to eliminate the degrees of freedom in non-compact directions. All supersymmetric nonlinear sigma models defined on the hermitian symmetric spaces are successfully formulated as gauge theories. 1Talk given at the International Symposium on \Quantum Chromodynamics and Color Con- finement" (Confinement 2000) , 7-10 March 2000, RCNP, Osaka, Japan. ∗e-mail: [email protected]. †e-mail: [email protected] 1 Introduction Two dimensional (2D) nonlinear sigma models and four dimensional non-abelian gauge theories have several similarities. Both of them enjoy the property of the asymptotic freedom. They are both massless in the perturbation theory, whereas they acquire the mass gap or the string tension in the non-perturbative treatment. Although it is difficult to solve QCD in analytical way, 2D nonlinear sigma models can be solved by the large N expansion and helps us to understand various non- perturbative phenomena in four dimensional gauge theories. -
Arxiv:1805.06347V1 [Hep-Th] 16 May 2018 Sa Rte O H Rvt Eerhfudto 08Awar 2018 Foundation Research Gravity the for Written Essay Result
Maximal supergravity and the quest for finiteness 1 2 3 Sudarshan Ananth† , Lars Brink∗ and Sucheta Majumdar† † Indian Institute of Science Education and Research Pune 411008, India ∗ Department of Physics, Chalmers University of Technology S-41296 G¨oteborg, Sweden and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences Nanyang Technological University, Singapore 637371 March 28, 2018 Abstract We show that N = 8 supergravity may possess an even larger symmetry than previously believed. Such an enhanced symmetry is needed to explain why this theory of gravity exhibits ultraviolet behavior reminiscent of the finite N = 4 Yang-Mills theory. We describe a series of three steps that leads us to this result. arXiv:1805.06347v1 [hep-th] 16 May 2018 Essay written for the Gravity Research Foundation 2018 Awards for Essays on Gravitation 1Corresponding author, [email protected] [email protected] [email protected] Quantum Field Theory describes three of the four fundamental forces in Nature with great precision. However, when attempts have been made to use it to describe the force of gravity, the resulting field theories, are without exception, ultraviolet divergent and non- renormalizable. One striking aspect of supersymmetry is that it greatly reduces the diver- gent nature of quantum field theories. Accordingly, supergravity theories have less severe ultraviolet divergences. Maximal supergravity in four dimensions, N = 8 supergravity [1], has the best ultraviolet properties of any field theory of gravity with two derivative couplings. Much of this can be traced back to its three symmetries: Poincar´esymmetry, maximal supersymmetry and an exceptional E7(7) symmetry. -
Introduction to String Theory A.N
Introduction to String Theory A.N. Schellekens Based on lectures given at the Radboud Universiteit, Nijmegen Last update 6 July 2016 [Word cloud by www.worldle.net] Contents 1 Current Problems in Particle Physics7 1.1 Problems of Quantum Gravity.........................9 1.2 String Diagrams................................. 11 2 Bosonic String Action 15 2.1 The Relativistic Point Particle......................... 15 2.2 The Nambu-Goto action............................ 16 2.3 The Free Boson Action............................. 16 2.4 World sheet versus Space-time......................... 18 2.5 Symmetries................................... 19 2.6 Conformal Gauge................................ 20 2.7 The Equations of Motion............................ 21 2.8 Conformal Invariance.............................. 22 3 String Spectra 24 3.1 Mode Expansion................................ 24 3.1.1 Closed Strings.............................. 24 3.1.2 Open String Boundary Conditions................... 25 3.1.3 Open String Mode Expansion..................... 26 3.1.4 Open versus Closed........................... 26 3.2 Quantization.................................. 26 3.3 Negative Norm States............................. 27 3.4 Constraints................................... 28 3.5 Mode Expansion of the Constraints...................... 28 3.6 The Virasoro Constraints............................ 29 3.7 Operator Ordering............................... 30 3.8 Commutators of Constraints.......................... 31 3.9 Computation of the Central Charge..................... -
S-Duality-And-M5-Mit
N . More on = 2 S-dualities and M5-branes .. Yuji Tachikawa based on works in collaboration with L. F. Alday, B. Wecht, F. Benini, S. Benvenuti, D. Gaiotto November 2009 Yuji Tachikawa (IAS) November 2009 1 / 47 Contents 1. Introduction 2. S-dualities 3. A few words on TN 4. 4d CFT vs 2d CFT Yuji Tachikawa (IAS) November 2009 2 / 47 Montonen-Olive duality • N = 4 SU(N) SYM at coupling τ = θ=(2π) + (4πi)=g2 equivalent to the same theory coupling τ 0 = −1/τ • One way to ‘understand’ it: start from 6d N = (2; 0) theory, i.e. the theory on N M5-branes, put on a torus −1/τ τ 0 1 0 1 • Low energy physics depends only on the complex structure S-duality! Yuji Tachikawa (IAS) November 2009 3 / 47 S-dualities in N = 2 theories • You can wrap N M5-branes on a more general Riemann surface, possibly with punctures, to get N = 2 superconformal field theories • Different limits of the shape of the Riemann surface gives different weakly-coupled descriptions, giving S-dualities among them • Anticipated by [Witten,9703166], but not well-appreciated until [Gaiotto,0904.2715] Yuji Tachikawa (IAS) November 2009 4 / 47 Contents 1. Introduction 2. S-dualities 3. A few words on TN 4. 4d CFT vs 2d CFT Yuji Tachikawa (IAS) November 2009 5 / 47 Contents 1. Introduction 2. S-dualities 3. A few words on TN 4. 4d CFT vs 2d CFT Yuji Tachikawa (IAS) November 2009 6 / 47 S-duality in N = 2 . SU(2) with Nf = 4 . -
1 the Spin Homomorphism SL2(C) → SO1,3(R) a Summary from Multiple Sources Written by Y
1 The spin homomorphism SL2(C) ! SO1;3(R) A summary from multiple sources written by Y. Feng and Katherine E. Stange Abstract We will discuss the spin homomorphism SL2(C) ! SO1;3(R) in three manners. Firstly we interpret SL2(C) as acting on the Minkowski 1;3 spacetime R ; secondly by viewing the quadratic form as a twisted 1 1 P × P ; and finally using Clifford groups. 1.1 Introduction The spin homomorphism SL2(C) ! SO1;3(R) is a homomorphism of classical matrix Lie groups. The lefthand group con- sists of 2 × 2 complex matrices with determinant 1. The righthand group consists of 4 × 4 real matrices with determinant 1 which preserve some fixed real quadratic form Q of signature (1; 3). This map is alternately called the spinor map and variations. The image of this map is the identity component + of SO1;3(R), denoted SO1;3(R). The kernel is {±Ig. Therefore, we obtain an isomorphism + PSL2(C) = SL2(C)= ± I ' SO1;3(R): This is one of a family of isomorphisms of Lie groups called exceptional iso- morphisms. In Section 1.3, we give the spin homomorphism explicitly, al- though these formulae are unenlightening by themselves. In Section 1.4 we describe O1;3(R) in greater detail as the group of Lorentz transformations. This document describes this homomorphism from three distinct per- spectives. The first is very concrete, and constructs, using the language of Minkowski space, Lorentz transformations and Hermitian matrices, an ex- 4 plicit action of SL2(C) on R preserving Q (Section 1.5). -
Physics of the Lorentz Group
Physics of the Lorentz Group Sibel Ba¸skal Department of Physics, Middle East Technical University, 06800 Ankara, Turkey e-mail: [email protected] Young S. Kim Center for Fundamental Physics, University of Maryland, College Park, Maryland 20742, U.S.A. e-mail: [email protected] Marilyn E. Noz Department of Radiology, New York University, New York, NY 10016 U.S.A. e-mail: [email protected] To be published in the IOP Concise Book Series. Preface When Newton formulated his law of gravity, he wrote down his formula applicable to two point particles. It took him 20 years to prove that his formula works also for extended objects such as the sun and earth. When Einstein formulated his special relativity in 1905, he worked out the transformation law for point particles. The question is what happens when those particles have space-time extensions. The hydrogen atom is a case in point. The hydrogen atom is small enough to be regarded as a particle obeyingp Einstein's law of Lorentz transformations including the energy-momentum relation E = p2 + m2. Yet, it is known to have a rich internal space-time structure, rich enough to provide the foundation of quantum mechanics. Indeed, Niels Bohr was interested in why the energy levels of the hydrogen atom are discrete. His interest led to the replacement of the orbit by a standing wave. Before and after 1927, Einstein and Bohr met occasionally to discuss physics. It is possible that they discussed how the hydrogen atom with an electron orbit or as a standing-wave looks to moving observers. -
Exceptional Field Theory and Supergravity Arnaud Baguet
Exceptional Field Theory and Supergravity Arnaud Baguet To cite this version: Arnaud Baguet. Exceptional Field Theory and Supergravity. High Energy Physics - Experiment [hep-ex]. Université de Lyon, 2017. English. NNT : 2017LYSEN022. tel-01563063 HAL Id: tel-01563063 https://tel.archives-ouvertes.fr/tel-01563063 Submitted on 17 Jul 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Numéro National de Thèse : 2017LYSEN022 Thèse de Doctorat de l’Université de Lyon opérée par l’École Normale Supérieure de Lyon École Doctorale 52 École Doctorale de Physique et d’Astrophysique de Lyon Soutenue publiquement le 30/06/2017, par : Arnaud Baguet Exceptional Field Theory and Supergravity - Théorie des Champs Exceptionnels et Supergravité Devant le jury composé de : Martin Cederwall Chalmers University of Technology Rapporteur François Delduc École Normale Supérieure de Lyon Examinateur Axel Kleinschmidt Max Planck Institute Postdam Rapporteur Michela Petrini Université Pierre et Marie Curie Examinatrice Henning Samtleben École Normale Supérieure de Lyon Directeur Contents 1 Introduction 9 1.1 String theory, dualities and supergravity . 11 1.2 The bosonic string . 13 1.3 Compactification and T-duality . 18 1.4 Double Field Theory . 21 1.5 Exceptional Field Theory .