DOCSLIB.ORG

HEP-TH-9408163 Address After Sept

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
HEP-TH-9408163 Address After Sept View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server SNUTP-94-73 CALT-68-1944 TOPOLOGY OF A NONTOPOLOGICAL MAGNETIC MONOPOLE Cho onkyu Lee Department of Physics and Center for Theoretical Physics Seoul National University, Seoul 151-742, Korea 12 Piljin Yi California Institute of Technology, Pasadena, CA 91125, U.S.A. ABSTRACT Certain nontop ological magnetic monop oles, recently found by Lee and Wein- b erg, are reinterpreted as top ological solitons of a non-Ab elian gauged Higgs mo del. Our study makes the nature of the Lee-Weinb erg monop oles more transparent, esp ecially with regard to their singularity structure. Submitted to Physics Letters B. HEP-TH-9408163 1 e-mail address: [email protected] 2 Address after Sept. 1, 1994: Physics Department, Columbia University, New York, NY 10027, U.S.A. When Dirac [1] founded the theory of magnetic monop oles in 1931, the monop ole was not something that p eople could not live without. Things changed a great deal in the seventies when 't Ho oft and Polyakov [2] showed that magnetic monop oles inevitably o ccur as solitons of sp ontaneously broken non-Ab elian gauge theories; such as all grand uni ed theories where an internal semi-simple gauge symmetry is sp ontaneously broken to U (1). Their existence is understo o d in terms of the nontrivial top ology of the vacuum manifold, and as such the non-Ab elian nature of the original gauge group plays a crucial role. In particular, the Dirac quantization rule is naturally enforced by the underlying non-Ab elian structure. Recently,however, Lee and Weinb erg [3] constructed a new class of nite-energy mag- netic monop oles in the context of a purely Ab elian gauge theory. Amazingly enough, the corresp onding U (1) p otential is simply that of a p oint Dirac monop ole (with the monop ole strength satisfying the Dirac quantization rule), yet the total energy is rendered nite by intro ducing a charged vector eld of p ositive gyromagnetic ratio and by ne-tuning a quartic self-interaction thereof. For more general values of the couplings, this theory to- gether with Einstein gravitywas found to pro duce new magnetically charged black hole solutions with hair [3]. One might b e tempted to conclude from this that the existence of the magnetic monop oles do es not require an underlying non-Ab elian structure, let alone a nontrivial top ology of the vacuum manifold. We b elieve this is a bit premature, and is misleading as far as this particular mo del is concerned. As p ointed out by Lee and Weinb erg [3], their U (1) theory may b e regarded as a gauge- xed version of the usual SO(3) Higgs mo del at some sp ecial values of the couplings. An imp ortant question to ask here is whether there exists such a hidden structure at other values of the couplings as well. In this letter, we will show that there is indeed a hidden non-Ab elian gauge symmetry for general values of the couplings, and that subsequently the integer-charged monop oles of Lee and Weinb erg may b e regarded as top ological solitons asso ciated with certain nonrenormalizable defor- mations of the SO(3) Higgs mo del. Adopting the radial gauge rather than the unitary gauge, we found that the apparent Dirac string disapp ears as usual, while the singularity at the origin still needs to b e examined. An imp ortantbypro duct of our study is a top o- logical understanding of the Dirac quantization rule for the integer-charged Lee-Weinb erg monop oles. 1 The Ab elian mo del of Ref.[3] consists of a U (1) electromagnetic p otential A ,acharged vector eld W , and a real scalar . The Lagrange densitywas chosen to have the form 1 1 g 2 L = F F jD W D W j + H F H H 4 2 4 4 1 2 2 @ @ m ()jW j V (); (1) 2 where F = @ A @ A and D W = @ W + ie A W . The magnetic moment H is given by the antisymmetric pro duct ie (W W W W ) so that g is the gyromagnetic ratio of the charged vector. Here, g and are p ositive constants, while m()vanishes at = 0 but is equal to m 6= 0 when is at its (nontrivial) vacuum value. As mentioned W ab ove, when g =2, = 1 and m()= e, this is nothing but the unitary gauge version of the sp ontaneously broken su(2) gauge theory of Ref.[2], and thus renormalizable. But for generic values of g and , the theory is nonrenormalizable. The ansatz for the unit-charged, spherically symmetric, Lee-Weinb erg monop ole can b e written most succinctly in term of the di erential forms A A dx and W W dx : 1 iu(r) p = (r ); A = (cos 1) d'; W = [ exp i' ][ d + i sin d']: (2) e e 2 u and are radial fuctions to b e determined by the eld equations and appropriate b oundary conditions. Note that the electromagnetic p otential is simply that of a p oint- like Dirac monop ole and the eld con guration app ears singular at origin, in addition to the presumably harmless Dirac string along the negative z -axis. Akey observation in 2 Ref.[3] is that, if the relationship 4 = g holds, the total energy of the resulting solution can b e actually nite despite this singular b ehaviour at origin. In addition to such a unit- charged solution, the Dirac quantization rule allows all integral and half-integral magnetic charges. Let us turn to the question of the hidden non-Ab elian structure. Consider the following a nonrenormalizable SO(3) gauge theory with the gauge connection 1-form B =(B dx ) T a a and a triplet Higgs = T . a g 2 1 1 a a 0 G G + F H H H L = 4 4 4 1 1 a a 2 2 a a a a ^ ^ (D ) (D ) (m (jj) e )(D ) ) (D V (jj) (3) 2 2 e a a @ + G is the non-Ab elian gauge eld strength asso ciated with B , while D abc b c a a ^ B and =jj. In addition, we de ned two gauge-invariantantisymmetric 2 3 tensor F and H as follows, 1 a a a b c ^ ^ ^ ^ F H G ; H (D ) (D ) : (4) abc e a 3 a 3 ^ Now in the unitary gauge = ,wemay identify with jj, A with B , and W p 1 2 with (B + iB )= 2. This results in the following reduction formulae: F ) F ; H ) H ; 3 G ) F H ; p 1 2 G + iG ) 2(D W D W ); a a 2 ^ ^ (D ) (D ) ) 2e W W ; a a 2 2 (D ) (D ) ) @ @ +2e W W : a a 0 Expanding the G G term, one easily notices that the SO(3) invariant Lagrangian L reduces to L of the apparently Ab elian theory of Lee and Weinb erg. According to the standard argument [4], all con gurations with a regular and nite asymptotic b ehaviour may b e classi ed in terms of a top ological winding numb er: I 1 i a b c ^ ^ ^ n = dS @ @ ; (5) ij k abc j k 8 where the integral is over the asymptotic two-sphere. Note that n is an integer in general, and the magnetic monop ole strength is related to this number by g = 4 n=e [5]. mag netic The unit-charged case (n = 1) is of sp ecial interest, b ecause the corresp onding solution has the spherical symmetry.For example, if g =2, = 1 and m = e, the n = 1 solution is given by the usual 't Ho oft-Polyakov monop ole. Actually, the ansatz (2) for the sp erically symmetric Lee-Weinb erg monop ole is exactly the same as that of the 't Ho oft-Polyakov monop ole but written in the unitary gauge. Written in the so-called radial gauge, the ansatz for the 't Ho oft-Polyakov monop ole has the following well-known hedgehog con guration: b c x dx abc a a a [1 u(r)]: (6) =^x (r); B = 2 er 3 F was previously used by `t Ho oft [2] to representphysical electromagnetic elds. 3 Gauge transforming to the unitary gauge, 1 a i'T i T i'T 3 2 3 x^ T =T with e e e ; (7) a 3 a lengthy but straightforward calculation shows that the hedgehog con guration (6) is indeed gauge-equivalent to the ansatz (2). This clearly demonstrates that the spheri- cally symmetric unit-charged Lee-Weinb erg monop ole has the top ological winding num- ber n = 1, and that the Dirac string apparent in (2) is sup er uous. Similar pro cedures for n>1 non-Ab elian con gurations should also lead to all integer-charged Lee-Weinb erg 4 monop oles automatically, although, due to the lack of the spherical symmetry, the ex- plicit forms of the necessary gauge transformations are more dicult to nd. Now that the Dirac string disapp eared by virtue of the radial gauge, let us concentrate on the p ossible singular structure at origin r = 0. Generalizing to include dyons [6] while a maintaining n =1,wemay mo dify the hedgehog con guration (6) to have nontrivial B . t b c x dx abc a a a a [1 u(r)] x^ v(r)dt: (8) =^x (r); B = 2 er On such con gurations, the total energy is given by the following functional of u, , and v .
Load more

Recommended publications
  • Band Spectrum Is D-Brane
    Prog. Theor. Exp. Phys. 2016, 013B04 (26 pages) DOI: 10.1093/ptep/ptv181 Band spectrum is D-brane Koji Hashimoto1,∗ and Taro Kimura2,∗ 1Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan 2Department of Physics, Keio University, Kanagawa 223-8521, Japan ∗E-mail: [email protected], [email protected] Received October 19, 2015; Revised November 13, 2015; Accepted November 29, 2015; Published January 24 , 2016 Downloaded from ............................................................................... We show that band spectrum of topological insulators can be identified as the shape of D-branes in string theory. The identification is based on a relation between the Berry connection associated with the band structure and the Atiyah–Drinfeld–Hitchin–Manin/Nahm construction of solitons http://ptep.oxfordjournals.org/ whose geometric realization is available with D-branes. We also show that chiral and helical edge states are identified as D-branes representing a noncommutative monopole. ............................................................................... Subject Index B23, B35 1. Introduction at CERN - European Organization for Nuclear Research on July 8, 2016 Topological insulators and superconductors are one of the most interesting materials in which theo- retical and experimental progress have been intertwined each other. In particular, the classification of topological phases [1,2] provided concrete and rigorous argument on stability and the possibility of topological insulators and superconductors. The key to finding the topological materials is their electron band structure. The existence of gapless edge states appearing at spatial boundaries of the material signals the topological property. Identification of possible electron band structures is directly related to the topological nature of topological insulators. It is important, among many possible appli- cations of topological insulators, to gain insight into what kind of electron band structure is possible for topological insulators with fixed topological charges.
    [Show full text]
  • Introductory Lectures on Quantum Field Theory
    Introductory Lectures on Quantum Field Theory a b L. Álvarez-Gaumé ∗ and M.A. Vázquez-Mozo † a CERN, Geneva, Switzerland b Universidad de Salamanca, Salamanca, Spain Abstract In these lectures we present a few topics in quantum field theory in detail. Some of them are conceptual and some more practical. They have been se- lected because they appear frequently in current applications to particle physics and string theory. 1 Introduction These notes are based on lectures delivered by L.A.-G. at the 3rd CERN–Latin-American School of High- Energy Physics, Malargüe, Argentina, 27 February–12 March 2005, at the 5th CERN–Latin-American School of High-Energy Physics, Medellín, Colombia, 15–28 March 2009, and at the 6th CERN–Latin- American School of High-Energy Physics, Natal, Brazil, 23 March–5 April 2011. The audience on all three occasions was composed to a large extent of students in experimental high-energy physics with an important minority of theorists. In nearly ten hours it is quite difficult to give a reasonable introduction to a subject as vast as quantum field theory. For this reason the lectures were intended to provide a review of those parts of the subject to be used later by other lecturers. Although a cursory acquaintance with the subject of quantum field theory is helpful, the only requirement to follow the lectures is a working knowledge of quantum mechanics and special relativity. The guiding principle in choosing the topics presented (apart from serving as introductions to later courses) was to present some basic aspects of the theory that present conceptual subtleties.
    [Show full text]
  • Arxiv:Hep-Th/0006117V1 16 Jun 2000 Oadmarolf Donald VERSION HYPER - Style
    Preprint typeset in JHEP style. - HYPER VERSION SUGP-00/6-1 hep-th/0006117 Chern-Simons terms and the Three Notions of Charge Donald Marolf Physics Department, Syracuse University, Syracuse, New York 13244 Abstract: In theories with Chern-Simons terms or modified Bianchi identities, it is useful to define three notions of either electric or magnetic charge associated with a given gauge field. A language for discussing these charges is introduced and the proper- ties of each charge are described. ‘Brane source charge’ is gauge invariant and localized but not conserved or quantized, ‘Maxwell charge’ is gauge invariant and conserved but not localized or quantized, while ‘Page charge’ conserved, localized, and quantized but not gauge invariant. This provides a further perspective on the issue of charge quanti- zation recently raised by Bachas, Douglas, and Schweigert. For the Proceedings of the E.S. Fradkin Memorial Conference. Keywords: Supergravity, p–branes, D-branes. arXiv:hep-th/0006117v1 16 Jun 2000 Contents 1. Introduction 1 2. Brane Source Charge and Brane-ending effects 3 3. Maxwell Charge and Asymptotic Conditions 6 4. Page Charge and Kaluza-Klein reduction 7 5. Discussion 9 1. Introduction One of the intriguing properties of supergravity theories is the presence of Abelian Chern-Simons terms and their duals, the modified Bianchi identities, in the dynamics of the gauge fields. Such cases have the unusual feature that the equations of motion for the gauge field are non-linear in the gauge fields even though the associated gauge groups are Abelian. For example, massless type IIA supergravity contains a relation of the form dF˜4 + F2 H3 =0, (1.1) ∧ where F˜4, F2,H3 are gauge invariant field strengths of rank 4, 2, 3 respectively.
    [Show full text]
  • Two-Dimensional Instantons with Bosonization and Physics of Adjoint QCD2
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server Preprint ITEP–TH–21/96 Two-Dimensional Instantons with Bosonization and Physics of Adjoint QCD2. A.V. Smilga ITEP, B. Cheremushkinskaya 25, Moscow 117259, Russia Abstract We evaluate partition functions ZI in topologically nontrivial (instanton) gauge sectors in the bosonized version of the Schwinger model and in a gauged WZNW model corresponding to QCD2 with adjoint fermions. We show that the bosonized model is equivalent to the fermion model only if a particular form of the WZNW action with gauge-invariant integrand is chosen. For the exact correspondence, it is necessary to 2 integrate over the ways the gauge group SU(N)/ZN is embedded into the full O(N −1) group for the bosonized matter field. For even N, one should also take into account the 2 n contributions of both disconnected components in O(N − 1). In that case, ZI ∝ m 0 for small fermion masses where 2n0 coincides with the number of fermion zero modes in n a particular instanton background. The Taylor expansion of ZI /m 0 in mass involves only even powers of m as it should. The physics of adjoint QCD2 is discussed. We argue that, for odd N, the discrete chiral symmetry Z2 ⊗Z2 present in the action is broken spontaneously down to Z2 and the fermion condensate < λλ¯ >0 is formed. The system undergoes a first order phase transition at Tc = 0 so that the condensate is zero at an arbitrary small temperature.
    [Show full text]
  • Five-Branes in Heterotic Brane-World Theories
    SUSX-TH/01-037 HUB-EP-01/34 hep-th/0109173 Five-Branes in Heterotic Brane-World Theories Matthias Br¨andle1∗ and Andr´eLukas2§ 1Institut f¨ur Physik, Humboldt Universit¨at Invalidenstraße 110, 10115 Berlin, Germany 2Centre for Theoretical Physics, University of Sussex Falmer, Brighton BN1 9QJ, UK Abstract The effective action for five-dimensional heterotic M-theory in the presence of five-branes is systemat- ically derived from Hoˇrava-Witten theory coupled to an M5-brane world-volume theory. This leads to a 1 five-dimensional N = 1 gauged supergravity theory on S /Z2 coupled to four-dimensional N = 1 theories residing on the two orbifold fixed planes and an additional bulk three-brane. We analyse the properties of this action, particularly the four-dimensional effective theory associated with the domain-wall vacuum state. arXiv:hep-th/0109173v2 8 Oct 2001 The moduli K¨ahler potential and the gauge-kinetic functions are determined along with the explicit relations between four-dimensional superfields and five-dimensional component fields. ∗email: [email protected] §email: [email protected] 1 Introduction A large class of attractive five-dimensional brane-world models can be constructed by reducing Hoˇrava-Witten theory [1, 2, 3] on Calabi-Yau three-folds. This procedure has been first carried out in Ref. [4, 5, 6] and it leads 1 to gauged five-dimensional N = 1 supergravity on the orbifold S /Z2 coupled to N = 1 gauge and gauge matter multiplets located on the two four-dimensional orbifold fixed planes. It has been shown [7]–[13] that a phenomeno- logically interesting particle spectrum on the orbifold planes can be obtained by appropriate compactifications.
    [Show full text]
  • Flux Tubes, Domain Walls and Orientifold Planar Equivalence
    Flux tubes, domain walls and orientifold planar equivalence Agostino Patella CERN GGI, 5 May 2011 Agostino Patella (CERN) Tubes and walls GGI, 5/5/11 1 / 19 Introduction Orientifold planar equivalence Orientifold planar equivalence OrQCD 2 SU(N) gauge theory (λ = g N fixed) with Nf Dirac fermions in the antisymmetric representation is equivalent in the large-N limit and in a common sector to AdQCD 2 SU(N) gauge theory (λ = g N fixed) with Nf Majorana fermions in the adjoint representation if and only if C-symmetry is not spontaneously broken. Agostino Patella (CERN) Tubes and walls GGI, 5/5/11 2 / 19 2 Z Z ff e−N W(J) = DADψDψ¯ exp −S(A, ψ, ψ¯) + N2 J(x)O(x)d4x Introduction Orientifold planar equivalence Gauge-invariant common sector AdQCD BOSONIC C-EVEN FERMIONIC C-EVEN BOSONIC C-ODD FERMIONIC C-ODD ~ w ­ OrQCD BOSONIC C-EVEN BOSONIC C-ODD COMMON SECTOR Agostino Patella (CERN) Tubes and walls GGI, 5/5/11 3 / 19 Introduction Orientifold planar equivalence Gauge-invariant common sector AdQCD BOSONIC C-EVEN FERMIONIC C-EVEN BOSONIC C-ODD FERMIONIC C-ODD ~ w ­ OrQCD BOSONIC C-EVEN BOSONIC C-ODD COMMON SECTOR 2 Z Z ff e−N W(J) = DADψDψ¯ exp −S(A, ψ, ψ¯) + N2 J(x)O(x)d4x lim WOr(J) = lim WAd(J) N→∞ N→∞ Agostino Patella (CERN) Tubes and walls GGI, 5/5/11 3 / 19 Introduction Orientifold planar equivalence Gauge-invariant common sector AdQCD BOSONIC C-EVEN FERMIONIC C-EVEN BOSONIC C-ODD FERMIONIC C-ODD ~ w ­ OrQCD BOSONIC C-EVEN BOSONIC C-ODD COMMON SECTOR 2 Z Z ff e−N W(J) = DADψDψ¯ exp −S(A, ψ, ψ¯) + N2 J(x)O(x)d4x hO(x ) ··· O(xn)i hO(x ) ···
    [Show full text]
  • Dirac Equation for Strings in Minkowski Space-Time and Then Study the Radial Vibrations of the String
    Dirac equation for strings Maciej Trzetrzelewski ∗ M. Smoluchowski Institute of Physics, Jagiellonian University, Lojasiewicza, St. 11, 30-348 Krak´ow, Poland Abstract Starting with a Nambu-Goto action, a Dirac-like equation can be constructed by taking the square-root of the momentum constraint. The eigenvalues of the resulting Hamiltonian are real and correspond to masses of the excited string. In particular there are no tachyons. A special case of radial oscillations of a closed string in Minkowski space-time admits exact solutions in terms of wave functions of the harmonic oscillator. 1 Introduction In 1962 Dirac considered the possibility that leptons may be described arXiv:1302.5907v3 [hep-th] 14 Feb 2018 by extended objects of spherical topology [1, 2]. In this way one could understand the muon as an excitation of the ground state of the membrane - the electron. Anticipating Nambu [3] and Goto [4] by almost a decade he introduced what is now known as a generalization of the Nambu-Goto action to the case of membranes. Using Bohr- Sommerfeld approximation for the Hamiltonian corresponding to the radial mode, one can then show [1] that the mass of the first excitation is about 53me where me is the mass of the electron. This is about a quarter of the observed mass of the muon. In fact, when instead of ∗e-mail: [email protected] 1 the Bohr-Sommerfeld approximation one uses, more precise, numeri- cal methods one finds that the correct value of the first excitation is about 43me [5, 6]. Therefore Dirac’s model ”explains” 1/5th of the actual value of the muon mass.
    [Show full text]
  • Introduction to String Theory
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server Introduction to String Theory Thomas Mohaupt Friedrich-Schiller Universit¨at Jena, Max-Wien-Platz 1, D-07743 Jena, Germany Abstract. We give a pedagogical introduction to string theory, D-branes and p-brane solutions. 1 Introductory remarks These notes are based on lectures given at the 271-th WE-Haereus-Seminar ‘Aspects of Quantum Gravity’. Their aim is to give an introduction to string theory for students and interested researches. No previous knowledge of string theory is assumed. The focus is on gravitational aspects and we explain in some detail how gravity is described in string theory in terms of the graviton excitation of the string and through background gravitational fields. We include Dirichlet boundary conditions and D-branes from the beginning and devote one section to p-brane solutions and their relation to D-branes. In the final section we briefly indicate how string theory fits into the larger picture of M-theory and mention some of the more recent developments, like brane world scenarios. The WE-Haereus-Seminar ‘Aspects of Quantum Gravity’ covered both main approaches to quantum gravity: string theory and canonical quantum gravity. Both are complementary in many respects. While the canonical approach stresses background independence and provides a non-perturbative framework, the cor- nerstone of string theory still is perturbation theory in a fixed background ge- ometry. Another difference is that in the canonical approach gravity and other interactions are independent from each other, while string theory automatically is a unified theory of gravity, other interactions and matter.
    [Show full text]
  • Electromagnetic Duality for Children
    Electromagnetic Duality for Children JM Figueroa-O'Farrill [email protected] Version of 8 October 1998 Contents I The Simplest Example: SO(3) 11 1 Classical Electromagnetic Duality 12 1.1 The Dirac Monopole ....................... 12 1.1.1 And in the beginning there was Maxwell... 12 1.1.2 The Dirac quantisation condition . 14 1.1.3 Dyons and the Zwanziger{Schwinger quantisation con- dition ........................... 16 1.2 The 't Hooft{Polyakov Monopole . 18 1.2.1 The bosonic part of the Georgi{Glashow model . 18 1.2.2 Finite-energy solutions: the 't Hooft{Polyakov Ansatz . 20 1.2.3 The topological origin of the magnetic charge . 24 1.3 BPS-monopoles .......................... 26 1.3.1 Estimating the mass of a monopole: the Bogomol'nyi bound ........................... 27 1.3.2 Saturating the bound: the BPS-monopole . 28 1.4 Duality conjectures ........................ 30 1.4.1 The Montonen{Olive conjecture . 30 1.4.2 The Witten e®ect ..................... 31 1.4.3 SL(2; Z) duality ...................... 33 2 Supersymmetry 39 2.1 The super-Poincar¶ealgebra in four dimensions . 40 2.1.1 Some notational remarks about spinors . 40 2.1.2 The Coleman{Mandula and Haag{ÃLopusza¶nski{Sohnius theorems .......................... 42 2.2 Unitary representations of the supersymmetry algebra . 44 2.2.1 Wigner's method and the little group . 44 2.2.2 Massless representations . 45 2.2.3 Massive representations . 47 No central charges .................... 48 Adding central charges . 49 1 [email protected] draft version of 8/10/1998 2.3 N=2 Supersymmetric Yang-Mills .
    [Show full text]
  • Kaluza-Klein Magnetic Monopole a La Taub-NUT
    Kaluza-Klein magnetic monopole a la Taub-NUT Nematollah Riazi∗ and S. Sedigheh Hashemi Department of Physics, Shahid Beheshti University, G.C., Evin, Tehran 19839, Iran October 16, 2018 Abstract We present a Taub-NUT Kaluza-Klien vacuum solution and using the standard Kaluza- Klein reduction, show that this solution is a static magnetic monopole in 3+1 dimensional spacetime. We find that the four dimensional matter properties do not obey the equation of state of radiation and there is no event horizon. A comparison with the available magnetic monopole solutions, the nature of the singularity, and the issue of vanishing or negative mass are discussed. 1 Introduction One of the oldest ideas that unify gravity and electromagnetism is the theory of Kaluza and Klein which extends space-time to five dimensions [1]. The physical motivation for this unification is that the vacuum solutions of the (4+1) Kaluza-Klein field equations reduce to the (3+1) Einstein field equations with effective matter and the curvature in (4 + 1) space induces matter in (3 + 1) dimensional space-time [2]. With this idea, the four dimensional energy-momentum tensor is derived from the geometry of an exact five dimensional vacuum solution, and the properties of matter such as density and pressure as well as electromagnetic properties are determined by such a solution. In other words, the field equations of both electromagnetism and gravity can be obtained from the pure five-dimensional geometry. Kaluza’s idea was that the universe has four spatial dimensions, and the extra dimension is compactified to form a circle so small as to be unobservable.
    [Show full text]
  • Thirty Years of Erice on the Brane1
    IMPERIAL-TP-2018-MJD-03 Thirty years of Erice on the brane1 M. J. Duff Institute for Quantum Science and Engineering and Hagler Institute for Advanced Study, Texas A&M University, College Station, TX, 77840, USA & Theoretical Physics, Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom & Mathematical Institute, Andrew Wiles Building, University of Oxford, Oxford OX2 6GG, United Kingdom Abstract After initially meeting with fierce resistance, branes, p-dimensional extended objects which go beyond particles (p = 0) and strings (p = 1), now occupy centre stage in the- oretical physics as microscopic components of M-theory, as the seeds of the AdS/CFT correspondence, as a branch of particle phenomenology, as the higher-dimensional pro- arXiv:1812.11658v2 [hep-th] 16 Jun 2019 genitors of black holes and, via the brane-world, as entire universes in their own right. Notwithstanding this early opposition, Nino Zichichi invited me to to talk about su- permembranes and eleven dimensions at the 1987 School on Subnuclear Physics and has continued to keep Erice on the brane ever since. Here I provide a distillation of my Erice brane lectures and some personal recollections. 1Based on lectures at the International Schools of Subnuclear Physics 1987-2017 and the International Symposium 60 Years of Subnuclear Physics at Bologna, University of Bologna, November 2018. Contents 1 Introduction 5 1.1 Geneva and Erice: a tale of two cities . 5 1.2 Co-authors . 9 1.3 Nomenclature . 9 2 1987 Not the Standard Superstring Review 10 2.1 Vacuum degeneracy and the multiverse . 11 2.2 Supermembranes .
    [Show full text]
  • D-Brane Primer
    D–Brane Primer Clifford V. Johnson Department of Mathematical Sciences Science Laboratories, South Road Durham DH1 3LE England, U.K. [email protected] Following is a collection of lecture notes on D–branes, which may be used by the reader as preparation for applications to modern research applications such as: the AdS/CFT and other gauge theory/geometry correspondences, Matrix The- ory and stringy non–commutative geometry, etc. In attempting to be reasonably self–contained, the notes start from classical point–particles and develop the sub- ject logically (but selectively) through classical strings, quantisation, D–branes, supergravity, superstrings, string duality, including many detailed applications. Selected focus topics feature D–branes as probes of both spacetime and gauge geometry, highlighting the role of world–volume curvature and gauge couplings, with some non–Abelian cases. Other advanced topics which are discussed are the (presently) novel tools of research such as fractional branes, the enhan¸con mecha- nism, D(ielectric)–branes and the emergence of the fuzzy/non–commutative sphere. (This is an expanded writeup of lectures given at ICTP, TASI, and BUSSTEPP.) Contents 1 Opening Remarks 4 2 String Worldsheet Perspective, Mostly 7 arXiv:hep-th/0007170v3 24 Aug 2000 2.1 ClassicalPointParticles . 7 2.2 ClassicalBosonicStrings. 9 2.3 QuantisedBosonicStrings . 23 2.4 Chan-PatonFactors . .. .. .. .. .. .. .. .. .. 33 2.5 The Closed String Partition Function . 34 2.6 UnorientedStrings .. .. .. .. .. .. .. .. .. .. 39 2.7 StringsinCurvedBackgrounds . 43 3 Target Spacetime Perspective, Mostly 47 3.1 T–DualityforClosedStrings . 47 3.2 TheCirclePartitionFunction . 51 3.3 Self–Duality and Enhanced Gauge Symmetry . 52 1 3.4 T–dualityinBackgroundFields .
    [Show full text]