Hep-Th] 19 Jun 2008 Pc Ie( Ult Soeo H Aoseape.We Example)

Total Page:16

File Type:pdf, Size:1020Kb

Hep-Th] 19 Jun 2008 Pc Ie( Ult Soeo H Aoseape.We Example) MIFP-07 Supercriticality of a Class of Critical String Cosmological Solutions Dimitri V. Nanopoulos1,2,3 and Dan Xie1 1George P. and Cynthia W.Mitchell Institute for Fundamental Physics, Texas A&M University, College Station, TX 77843, USA 2Astroparticle physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, TX 77381, USA 3Academy of Athens, Division of Nature Sciences, 28 panepistimiou Avenue, Athens 10679, Greece (Dated: May 26, 2018) For a class of Friedmann-Robertson-Walker-type string solutions with compact hyperbolic spatial slices formulated in the critical dimension, we find the world sheet conformal field theory which involves the linear dilaton and Wess-Zumino-Witten-type model with a compact hyperbolic target space. By analyzing the infrared spectrum, we conclude that the theory is actually supercritical due to modular invariance. Thus, taking into account previous results, we conclude that all simple non- trivial string cosmological solutions are in fact supercritical. In addition, we discuss the relationship of this background with the Supercritical String Cosmology (SSC). PACS numbers: I. INTRODUCTION expect that strings experience the space-time dimensions in a novel way, and it may be possible that string theory String theory is usually formulated in the critical di- formulated in critical dimensions actually exhibits non- mension (D=26 for the bosonic string, and D=10 for the critical behavior, i.e. the number of effective space time dimensions in which strings can freely oscillate is larger superstring ), and there are various ways to justify why this is the natural choice[1]. The idea of a critical dimen- than the critical dimension. sion has been firmly entrenched in the way that string In [6], the authors analyzed the conformal field the- theory is usually formulated, and it is widely taken for ory of FRW type solutions with space curvature κ = 0 granted that this should be the case in most studies. Nev- and κ = +1; it was shown that the space dimensions ertheless, it is possible to formulate string theory in a should be supercritical. In this paper, we will consider dimension other than the critical dimension, and such a the case with space curvature κ = 1. This solution did way of formulating string theory finds a useful applica- not attract much attention because− conformal field the- tion in studying time-varying backgrounds such as those ory with hyperbolic target space is hard to study. For which are necesssary for cosmology [2][3]. this solution, we can choose the time-like linear dilaton There are several reasons to suspect that non-critical and the level of the hyperbolic CFT properly so that the string theory is relevant to the web of string duality. The space time dimensions are critical. This solution is triv- first clue comes from Cosmology. Observational data ial if the hyperbolic manifold is noncompact because the from the SnIa [4] project and WMAP 1, 3 [5] strongly background is only part of the flat Minkowski space. The suggests that the universe is currently in an accelerating amazing thing is that if we make the hyperbolic manifold phase, which may be explained by the presence of dark compact, (to make the solution topologically nontrivial) energy. String theory, as a theory of quantum gravity, the actual space time dimensions of this background is should give an explanation of the dark energy. However, supercritical. So we conclude for all the nontrivial FRW it is very difficult to find exact time-dependent solutions arXiv:0710.2312v2 [hep-th] 19 Jun 2008 type solutions, the theory should be formulated in non- in critical string theory. However, it has been shown in critical dimensions. [6][7] that if one goes beyond the critical dimension, one can find simple time-dependent Friedmann-Robertson- This paper is organized in the following way: In section Walker (FRW) solutions with a time-like linear dilaton. II, we discuss the cosmological solutions derived from the So-called supercritical strings (for strings with dimension string equations of motion and the quantization of the su- D>Dcritical) may then also provide an explanation for percritical linear dilaton background. It is shown that for the existence of dark energy[8]. this simple time dependent background, the infrared (IR) From the theoretical point of view, past experience tell and ultraviolet (UV) behaviors are changed drastically. us that strings probe space time in a very different way In section III, we discuss the stability of the cosmological than we may intuitively think. A compelling example solutions. We find that the pseudotachyon modes do not is the emergence of M theory, where when we study the imply the instability of the background. In section IV, strong coupling behavior of Type IIA string theory, the we study the cosmological solutions with the compact theory develops a new dimension, and the theory is then hyperbolic spatial section in critical dimension and we formulated in 11 dimensions! The extended nature of the find that the theory is indeed supercritical. In section V, string reveals many amazing things about the property of the relation of this background with supercritical string space time (T duality is one of the famous example). We cosmology is pointed out. 2 II. COSMOLOGICAL SOLUTIONS AND THE non-trivial; the remarkable thing is that this background QUANTIZATION with the compact hyperbolic section is indeed supercrit- ical. Before we get into the discussion of the hyperbolic To study the nontrivial space time background, it is case, it is very useful to give a review of the well-studied quite useful to start with the string world sheet non- solutions with κ = 0 and κ = 1, we will find some generic linear sigma model in curved space time. The bosonic features of time-dependent solutions. string action reads: κ 1 2 αβ µν A. Spectrum of Cosmological Solutions with = 0 = ′ d σ√ h[h ∂ X ∂ X G + S −4πα − α µ β ν and κ = 1 Z P ′ The simplest time dependent background is the so- iǫ Bµν ∂ X ∂ X + α RΦ(X)]. (1) αβ α µ β ν called supercritical linear dilaton background (SCLD), The equation of motion for the background fields can this solution can be derived if we take κ = 0 in our sec- be derived from the requirement that the β functions ond class of solutions. A discussion of this background of this two dimensional field theory vanish to one-loop may also be found in[11]. Regardless of its simplicity, we order, where the β functions can be found in [9][10]. can definitely learn a lot from studying this background We are interested in finding the four dimensional FRW due to the nontrivial time dependence of the solution. type solution (we assume that the four dimensional CFT The background reads: is decoupled from the internal Conformal Field Theory 0 Gµν = ηµν , Φ= 2QX . (6) (CFT)). We have found in [6] the following simple and − asymptotically unique cosmological solutions (we only The central charge of this CFT is write the four large dimension with the internal part of c = D 12Q2. (7) the background suppressed) : − 1. The Einstein static universe, with the background The anomaly cancelation requires that c = 26 for bosonic fields as (the metric is expressed in the Einstein frame, string, so for Q real, it is clear that the space time di- the relation of the metric between string frame and Ein- mension is larger than the critical dimension. stein frame is gE = e 2Φ/(D 2)GS ) µν − − µν The effect of the linear dilaton is to change the world Φ0 0 sheet energy-momentum tensor to the form (where we Φ=Φ0, b =2e− √κX . (2) ′ have set α = 2) Here we have a constant dilaton, while the axion b is re- 1 µ 2 0 lated to the NS field strength through the duality relation Tzz = ∂zX ∂zXµ Q∂z X . (8) 2φ ρ −2 − Hλµν = e ǫλµνρ b, and the metric is given by ▽ We can quantize the theory by using the conventional dr2 (ds)2 = (dX0)2 + [ + r2(dθ2 + sin2 θdφ2)]. mode expansion, whic is possible, because the theory is − 1 κr2 Weyl invariant and reparameterization invariant, and be- − (3) cause we can gauge fix the world-sheet metric as hij = 2. The second class of solutions involves both a non- δij ). trivial dilaton and the non-trivial axion field. The solu- The Virasoro generators are [6] tion is 0 1 µ 0 QX Ln =: an kakµ :+iQ(n + 1)an, (9) 0 2 e 2 − Φ= 2QX , b =2Q √κ( ), (4) k − Q X where we consider the left moving modes only; the right while the metric is given by moving modes have the similar form. The commutation relation for the creation and annihilation operators are dr2 (ds)2 = (dt)2 + t2[ + r2(dθ2 + sin2 θdφ2)]. (5) familiar: − 1 κr2 − [aµ ,aν ]= mηµν δ . (10) The κ is the curvature of the spatial slice, and X0 is the m n m+n world sheet time coordinate, it is related to the Einstein The hermiticity relations of the Virasoro generators 0 1 QX + time coordinate as t = e . The central charge deficit Ln = L n dictate that Q − is δc = cI 22 (1 + κ), so only for κ = 1, can we find µ+ µ µ0 − ∝ − an = a n + i2Qη δn. (11) the cosmological solutions in critical dimension, while for − the flat and positive curvature the theory is supercritical. This relation means that the zeroth component has a However, for κ = 1, the solution is trivial due to the fixed imaginary part: fact that this background− is only part of the flat space. We can take a quotient of this space to make the solution p0 = E + iQ.
Recommended publications
  • Notes on Statistical Field Theory
    Lecture Notes on Statistical Field Theory Kevin Zhou [email protected] These notes cover statistical field theory and the renormalization group. The primary sources were: • Kardar, Statistical Physics of Fields. A concise and logically tight presentation of the subject, with good problems. Possibly a bit too terse unless paired with the 8.334 video lectures. • David Tong's Statistical Field Theory lecture notes. A readable, easygoing introduction covering the core material of Kardar's book, written to seamlessly pair with a standard course in quantum field theory. • Goldenfeld, Lectures on Phase Transitions and the Renormalization Group. Covers similar material to Kardar's book with a conversational tone, focusing on the conceptual basis for phase transitions and motivation for the renormalization group. The notes are structured around the MIT course based on Kardar's textbook, and were revised to include material from Part III Statistical Field Theory as lectured in 2017. Sections containing this additional material are marked with stars. The most recent version is here; please report any errors found to [email protected]. 2 Contents Contents 1 Introduction 3 1.1 Phonons...........................................3 1.2 Phase Transitions......................................6 1.3 Critical Behavior......................................8 2 Landau Theory 12 2.1 Landau{Ginzburg Hamiltonian.............................. 12 2.2 Mean Field Theory..................................... 13 2.3 Symmetry Breaking.................................... 16 3 Fluctuations 19 3.1 Scattering and Fluctuations................................ 19 3.2 Position Space Fluctuations................................ 20 3.3 Saddle Point Fluctuations................................. 23 3.4 ∗ Path Integral Methods.................................. 24 4 The Scaling Hypothesis 29 4.1 The Homogeneity Assumption............................... 29 4.2 Correlation Lengths.................................... 30 4.3 Renormalization Group (Conceptual)..........................
    [Show full text]
  • Scale Without Conformal Invariance in Membrane Theory
    Scale without conformal invariance in membrane theory Achille Mauria,∗, Mikhail I. Katsnelsona aRadboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands Abstract We investigate the relation between dilatation and conformal symmetries in the statistical mechanics of flex- ible crystalline membranes. We analyze, in particular, a well-known model which describes the fluctuations of a continuum elastic medium embedded in a higher-dimensional space. In this theory, the renormalization group flow connects a non-interacting ultraviolet fixed point, where the theory is controlled by linear elas- ticity, to an interacting infrared fixed point. By studying the structure of correlation functions and of the energy-momentum tensor, we show that, in the infrared, the theory is only scale-invariant: the dilatation symmetry is not enhanced to full conformal invariance. The model is shown to present a non-vanishing virial current which, despite being non-conserved, maintains a scaling dimension exactly equal to D − 1, even in presence of interactions. We attribute the absence of anomalous dimensions to the symmetries of the model under translations and rotations in the embedding space, which are realized as shifts of phonon fields, and which protect the renormalization of several non-invariant operators. We also note that closure of a sym- metry algebra with both shift symmetries and conformal invariance would require, in the hypothesis that phonons transform as primary fields, the presence of new shift symmetries which are not expected to hold on physical grounds. We then consider an alternative model, involving only scalar fields, which describes effective phonon-mediated interactions between local Gaussian curvatures.
    [Show full text]
  • Statistical Field Theory University of Cambridge Part III Mathematical Tripos
    Preprint typeset in JHEP style - HYPER VERSION Michaelmas Term, 2017 Statistical Field Theory University of Cambridge Part III Mathematical Tripos David Tong Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Wilberforce Road, Cambridge, CB3 OBA, UK http://www.damtp.cam.ac.uk/user/tong/sft.html [email protected] –1– Recommended Books and Resources There are a large number of books which cover the material in these lectures, although often from very di↵erent perspectives. They have titles like “Critical Phenomena”, “Phase Transitions”, “Renormalisation Group” or, less helpfully, “Advanced Statistical Mechanics”. Here are some that I particularly like Nigel Goldenfeld, Phase Transitions and the Renormalization Group • Agreatbook,coveringthebasicmaterialthatwe’llneedanddelvingdeeperinplaces. Mehran Kardar, Statistical Physics of Fields • The second of two volumes on statistical mechanics. It cuts a concise path through the subject, at the expense of being a little telegraphic in places. It is based on lecture notes which you can find on the web; a link is given on the course website. John Cardy, Scaling and Renormalisation in Statistical Physics • Abeautifullittlebookfromoneofthemastersofconformalfieldtheory.Itcoversthe material from a slightly di↵erent perspective than these lectures, with more focus on renormalisation in real space. Chaikin and Lubensky, Principles of Condensed Matter Physics • Shankar, Quantum Field Theory and Condensed Matter • Both of these are more all-round condensed matter books, but with substantial sections on critical phenomena and the renormalisation group. Chaikin and Lubensky is more traditional, and packed full of content. Shankar covers modern methods of QFT, with an easygoing style suitable for bedtime reading. Anumberofexcellentlecturenotesareavailableontheweb.Linkscanbefoundon the course webpage: http://www.damtp.cam.ac.uk/user/tong/sft.html.
    [Show full text]
  • The Quantized Fermionic String
    Class 2: The quantized fermionic string Canonical quantization Light-cone quantization Spectrum of the fermionic string, GSO projection . The super-Virasoro constraints, which allow to eliminate the ghosts, are implemented and analyzed in essentially the same way as in the bosonic string. One new feature is the existence of two sectors: bosonic and fermionic, which have to be studied separately. To remove the tachyon one has to perform the so-called GSO projection, which guarantees space-time supersymmetry of the ten-dimensional theory. There are two possible space-time supersymmetric GSO projections which result in the Type IIA and Type IIB superstring. Summary The fermionic string is quantized analogously to the bosonic string, although now we'll find the critical dimension is 10 . One new feature is the existence of two sectors: bosonic and fermionic, which have to be studied separately. To remove the tachyon one has to perform the so-called GSO projection, which guarantees space-time supersymmetry of the ten-dimensional theory. There are two possible space-time supersymmetric GSO projections which result in the Type IIA and Type IIB superstring. Summary The fermionic string is quantized analogously to the bosonic string, although now we'll find the critical dimension is 10 The super-Virasoro constraints, which allow to eliminate the ghosts, are implemented and analyzed in essentially the same way as in the bosonic string. To remove the tachyon one has to perform the so-called GSO projection, which guarantees space-time supersymmetry of the ten-dimensional theory. There are two possible space-time supersymmetric GSO projections which result in the Type IIA and Type IIB superstring.
    [Show full text]
  • Lectures on the Renormalization Group in Statistical Physics
    Lectures on the renormalization group in statistical physics Riccardo Fantoni∗ Dipartimento di Scienze Molecolari e Nanosistemi, Universit`aCa’ Foscari Venezia, Calle Larga S. Marta DD2137, I-30123 Venezia, Italy (Dated: April 10, 2017) We review some of the ideas of the renormalization group in the statistical physics of classical and quantum fluids theory. The origin, the nature, the basis, the formulation, the critical exponents and scaling, relevance, irrelevance, and marginality, universality, and Wilson’s concept of flows and fixed point in a space of Hamiltonians. CONTENTS I. Notation 1 II. The origin of RG 2 III. The decay of correlation functions 3 IV. The challanges posed by critical phenomena 4 V. The critical exponents 7 A. The classical exponent values 7 B. The Ising exponent values 8 C. Exponent relations 8 VI. The Gaussian model and the upper critical dimension 9 VII. The task of RG 9 VIII. The basis and formulation 10 Acknowledgments 14 References 14 In a recent Review of Modern Physics, M. E. Fisher (Fisher, 1998) presented, to a wide audience, the ideas of the Renormalization Group (RG) theory behind statistical mechanics of matter physics and Quantum Field Theory (QFT). We will also follow the lectures given by N. Goldenfeld (Goldenfeld, 1992) at the University of Illinois at Urbana- Champaign in 1992. Despite its name the theory is not really about a group but about a semigroup since the set of transformations involved is not necessarily invertible. The theory is thought as one of the underlying ideas in the theoretical structure of QFT even if the roots of RG theory has to be looked upon the theory of critical phenomena of the statistical mechanics of matter physics.
    [Show full text]
  • (A) Ds Backgrounds from Asymmetric Orientifolds
    hep-th/0106209 SLAC-PUB-8869 NSF-ITP-01- (A)dS Backgrounds from Asymmetric Orientifolds Eva Silverstein Department of Physics and SLAC, Stanford University, Stanford, CA 94305/94309 Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 I present asymmetric orientifold models which, with the addition of RR fluxes, fix all the NS NS moduli including the dilaton. In critical string theory, this gives new AdS backgrounds with (discretely tunably) weak string coupling. Extrapolating to super- critical string theory, this construction leads to a promising candidate for a metastable de Sitter background with string coupling of order 1/10 and dS radius of order 100 times the string scale. Extrapolating further to larger and larger super-critical dimension suggests the possibility of finding de Sitter backgrounds with weaker and weaker string coupling. arXiv:hep-th/0106209v1 22 Jun 2001 This note is an updated version of the last part of my Strings 2001 talk. June 2001 1. Introduction Because of bounds on Brans-Dicke forces and on time-dependence of couplings, it is of interest to fix the moduli in string/M theory. The diverse ingredients arising in modern string backgrounds, including branes and RR fields, introduce new sources of moduli as well as new forces which can help stabilize the moduli. In 2 I will present a six-dimensional model where the NS-NS moduli (including the § dilaton) are fixed, so that there are no runaway directions in moduli space. The strategy, as outlined in the last few minutes of my Strings 2001 talk, is to balance the first few terms in string perturbation theory off of each other by introducing large flux quanta and/or brane charges, in such a way that a minimum arises in the effective potential in a controlled regime at weak string coupling.
    [Show full text]
  • 2. My First Path Integral
    2. My First Path Integral It’s now time to understand a little better how to deal with the path integral βF[m(x)] Z = m(x) e− (2.1) D Z Our strategy – at least for now – will be to work in situations where the saddle point dominates, with the integral giving small corrections to this result. In this regime, we can think of the integral as describing the thermal fluctuations of the order parameter m(x) around the equilibrium configuration determined by the saddle point. As we will see, this approach fails to work at the critical point, which is the regime we’re most interested in. We will then have to search for other techniques, which we will describe in Section 3. Preparing the Scene Before we get going, we’re going to change notation. First, we will change the name of our main character and write the magnetisation as m(x) φ(x) ! If you want a reason for this, I could tell you that the change of name is in deference to universality and the fact that the field could describe many things, not just magnetisa- tion. But the real reason is simply that fields in path integrals should have names like φ. (This is especially true in quantum field theory where m is reserved for the mass of the particle.) We start by setting B =0;we’llturnB back on in Section 2.2.Thefreeenergyis then 1 1 1 F [φ(x)] = ddx ↵ (T )φ2 + ↵ (T )φ4 + γ(T )( φ)2 + ... 2 2 4 4 2 r Z Roughly speaking, path integrals are trivial to do if F [φ(x)] is quadratic in φ,and possible to do if the higher order terms in F [φ(x)] give small corrections.
    [Show full text]
  • Shamit Kachru Professor of Physics and Director, Stanford Institute for Theoretical Physics
    Shamit Kachru Professor of Physics and Director, Stanford Institute for Theoretical Physics CONTACT INFORMATION • Administrative Contact Dan Moreau Email [email protected] Bio BIO Starting fall of 2021, I am winding down a term as chair of physics and then taking an extended sabbatical/leave. My focus during this period will be on updating my background and competence in rapidly growing new areas of interest including machine learning and its application to problems involving large datasets. My recent research interests have included mathematical and computational studies of evolutionary dynamics; field theoretic condensed matter physics, including study of non-Fermi liquids and fracton phases; and mathematical aspects of string theory. I would characterize my research programs in these three areas as being in the fledgling stage, relatively recently established, and well developed, respectively. It is hard to know what the future holds, but you can get some idea of the kinds of things I work on by looking at my past. Highlights of my past research include: - The discovery of string dualities with 4d N=2 supersymmetry, and their use to find exact solutions of gauge theories (with Cumrun Vafa) - The construction of the first examples of AdS/CFT duality with reduced supersymmetry (with Eva Silverstein) - Foundational papers on string compactification in the presence of background fluxes (with Steve Giddings and Joe Polchinski) - Basic models of cosmic acceleration in string theory (with Renata Kallosh, Andrei Linde, and Sandip Trivedi)
    [Show full text]
  • Critical Points of Coupled Vector-Ising Systems. Exact Results
    Critical points of coupled vector-Ising systems. Exact results Gesualdo Delfino1,2 and Noel Lamsen1,2 1SISSA, Via Bonomea 265, 34136 Trieste, Italy 2INFN sezione di Trieste, 34100 Trieste, Italy Abstract We show that scale invariant scattering theory allows to exactly determine the critical points of two-dimensional systems with coupled O(N) and Ising order pameters. The results are obtained for N continuous and include criticality of loop gas type. In particular, for N =1 we exhibit three critical lines intersecting at the Berezinskii-Kosterlitz-Thouless transition point of the Gaussian model and related to the Z4 symmetry of the isotropic Ashkin-Teller model. For N = 2 we classify the critical points that can arise in the XY-Ising model and provide exact answers about the critical exponents of the fully frustrated XY model. arXiv:1902.09901v1 [cond-mat.stat-mech] 26 Feb 2019 When a statistical mechanical system possesses two order parameters, phase transitions associated with each of them can take place at different points of the phase diagram. It is possible, however, that the two types of ordering set in at the same point, and that this gives rise to novel critical behavior with new critical exponents. The example of a vector order parameter for O(N) symmetry coupled to a scalar (Ising) order parameter for Z2 symmetry is paradigmatic of the combination of continuous and discrete symmetries and was addressed since the early days of the perturbative expansion in 4 ε dimensions [1]. The case N = 2 (XY- − Ising model) [2] has been higly debated in two dimensions also because it shares the ground state degeneracy of the fully frustrated (FF) XY model [3] describing a Josephson-junction array in a magnetic field [4].
    [Show full text]
  • Introduction to Superstring Theory
    Introduction to Superstring Theory Carmen N´u~nez IAFE (UBA-CONICET) & PHYSICS DEPT. (University of Buenos Aires) VI ICTP LASS 2015 Mexico, 26 October- 6 November 2015 . Programme Class 1: The classical fermionic string Class 2: The quantized fermionic string Class 3: Partition Function Class 4: Interactions . Outline Class 1: The classical fermionic string The action and its symmetries Gauge fixing and constraints Equations of motion and boundary conditions Oscillator expansions . The spectra of bosonic strings contain a tachyon ! it might indicate the vacuum has been incorrectly identified. The mass squared of a particle T is the quadratic term in the 2 @2V (T ) j − 4 ) action: M = @T 2 T =0 = α0 = we are expanding around a maximum of V . If there is some other stable vacuum, this is not an actual inconsistency. Why superstrings? . The mass squared of a particle T is the quadratic term in the 2 @2V (T ) j − 4 ) action: M = @T 2 T =0 = α0 = we are expanding around a maximum of V . If there is some other stable vacuum, this is not an actual inconsistency. Why superstrings? The spectra of bosonic strings contain a tachyon ! it might indicate the vacuum has been incorrectly identified. If there is some other stable vacuum, this is not an actual inconsistency. Why superstrings? The spectra of bosonic strings contain a tachyon ! it might indicate the vacuum has been incorrectly identified. The mass squared of a particle T is the quadratic term in the 2 @2V (T ) j − 4 ) action: M = @T 2 T =0 = α0 = we are expanding around a maximum of V .
    [Show full text]
  • Statistical Field Theory University of Cambridge Part III Mathematical Tripos
    Preprint typeset in JHEP style - HYPER VERSION Michaelmas Term, 2017 Statistical Field Theory University of Cambridge Part III Mathematical Tripos David Tong Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Wilberforce Road, Cambridge, CB3 OBA, UK http://www.damtp.cam.ac.uk/user/tong/sft.html [email protected] { 1 { Recommended Books and Resources There are a large number of books which cover the material in these lectures, although often from very different perspectives. They have titles like \Critical Phenomena", \Phase Transitions", \Renormalisation Group" or, less helpfully, \Advanced Statistical Mechanics". Here are some that I particularly like • Nigel Goldenfeld, Phase Transitions and the Renormalization Group A great book, covering the basic material that we'll need and delving deeper in places. • Mehran Kardar, Statistical Physics of Fields The second of two volumes on statistical mechanics. It cuts a concise path through the subject, at the expense of being a little telegraphic in places. It is based on lecture notes which you can find on the web; a link is given on the course website. • John Cardy, Scaling and Renormalisation in Statistical Physics A beautiful little book from one of the masters of conformal field theory. It covers the material from a slightly different perspective than these lectures, with more focus on renormalisation in real space. • Chaikin and Lubensky, Principles of Condensed Matter Physics • Shankar, Quantum Field Theory and Condensed Matter Both of these are more all-round condensed matter books, but with substantial sections on critical phenomena and the renormalisation group. Chaikin and Lubensky is more traditional, and packed full of content.
    [Show full text]
  • Gauge Fields, Scalars, Warped Geometry, and Strings
    SLAC-PUB-8671 December 2000 hep-th/0010144 Gauge Fields, Scalars, Warped Geometry, and Strings Eva Silverstein Department of Physics Stanford University, Stanford, CA 94305 Stanford Linear Accelerator Center Stanford University, Stanford, CA 94309 Presented at the Strings 2000 Conference, 7/10/2000—7/15/2000, Ann Arbor, MI, USA Stanford Linear Accelerator Center, Stanford University, Stanford, CA 94309 Work supported by Department of Energy contract DE–AC03–76SF00515. hep-th/0010144 SLAC-PUB-8671 Gauge Fields, Scalars, Warp ed Geometry, and Strings EvaSilverstein DepartmentofPhysics and SLAC Stanford University Stanford, CA 94305/94309 We review results on several interesting phenomena in warp ed compacti cations of M theory,aspresented at Strings 2000. The b ehavior of gauge elds in dimensional reduction from d +1 to d dimensions in various backgrounds is explained from the p ointof view of the holographic duals (and a p oint raised in the question session at the conference is addressed). We summarize the role of additional elds (in particular scalar elds) in 5d warp ed geometries in making it p ossible for Poincare-invariant domain wall solutions to exist to a nontrivial order in a controlled approximation scheme without ne-tuning arXiv:hep-th/0010144 v2 19 Oct 2000 of parameters in the 5d action (and comment on the status of the singularities arising in the general relativistic description of these solutions). Finally,we discuss brie y the emergence of excitations of wrapp ed branes in warp ed geometries whose e ective thickness, as measured along the Poincare slices in the geometry, grows as the energy increases.
    [Show full text]