Aspects of Gauge-Gravity Duality

Abstract

In this Ph.D. thesis, we study various backgrounds in Type IIB supergravity which admit interpretations in terms a dual field theory, and compute properties such as effective potentials and spectra, using both holographic and field theoretic methods. First, we study the phase structure of beta-deformed N=4 SYM on S3 at weak and strong 't Hooft coupling. We compute the one-loop effective potential, and find that at near critical chemical potential and small finite temperature, there is a metastable state at the origin of moduli space. We derive the gravitational background describing the theory at strong coupling, and by performing a probe-brane calculation, we find qualitative agreement between the weak and strong coupling results. Next, we study gravitational backgrounds obtained by wrapping Nc D5 color branes on an S2 inside a CY3-fold, and Nf D5 backreacting flavor branes on a non-compact two-cycle inside the same CY3-fold. These backgrounds are believed to be dual to certain SQCD-like theories. We compute how the spectrum depends on the number of flavors, and find that the mass of the lightest scalar glueball increases with the number of flavors until the point Nf=2Nc is reached after which the opposite behaviour is observed. Finally, we consider a class of backgrounds that exhibit walking behaviour, i.e. a suitably defined four-dimensional gauge coupling stays nearly constant in an intermediate energy regime. The breaking of approximate scale invariance has been conjectured to lead to the existence of a light scalar in the spectrum. This so-called dilaton would be the pseudo-Goldstone boson of dilatations. Using holographic techniques, we compute the spectrum and find a light state whose mass is suppressed by the length of the walking region, suggesting that this might be the dilaton.

Ph.D. Thesis. 119 pages. 13 figures

References in corpus (45)

• Towards the large N limit of pure N=1 super Yang Mills
• Embedding AdS Black Holes in Ten and Eleven Dimensions
• Duality in the Type--II Superstring Effective Action
• Phases of R-charged Black Holes, Spinning Branes and Strongly Coupled Gauge Theories
• Charged and rotating AdS black holes and their CFT duals
• The Coulomb Branch of Gauge Theory from Rotating Branes
• Lattice Study of the Conformal Window in QCD-like Theories
• Chiral symmetry breaking as open string tachyon condensation
• Minimal Walking on the Lattice
• Towards the String Dual of N=1 SQCD-like Theories
• Higher representations on the lattice: numerical simulations. SU(2) with adjoint fermions
• Zero of the discrete beta function in SU(3) lattice gauge theory with color sextet fermions
• A first order deconfinement transition in large N Yang-Mills theory on a small 3-sphere
• Marginal and Relevant Deformations of N=4 Field Theories and Non-Commutative Moduli Spaces of Vacua
• The physics of eight flavours
• Thermodynamics of spinning D3-branes
• Discrete Torsion, AdS/CFT and duality
• D3-D7 Quark-Gluon Plasmas
• Phase Diagram of N=4 Super-Yang-Mills Theory with R-Symmetry Chemical Potentials
• Phase structure of SU(3) gauge theory with two flavors of symmetric-representation fermions
• Finite temperature effective action, AdS_5 black holes, and 1/N expansion
• Glueballs vs. Gluinoballs: Fluctuation Spectra in Non-AdS/Non-CFT
• Bulk Dynamics in Confining Gauge Theories
• On deformed gauge theories and their string/M-theory duals
• Klebanov-Witten theory with massive dynamical flavors
• Comments on the String dual to N=1 SQCD
• Blackhole/String Transition for the Small Schwarzschild Blackhole of $Ad{S}_5\times S^5$ and Critical Unitary Matrix Models
• Wilson Loops in string duals of Walking and Flavored Systems
• Deconstruction of the Maldacena-Nunez Compactification
• Heavy quark potential with dynamical flavors: a first order transition
• Matching the Hagedorn temperature in AdS/CFT
• R-charged AdS_{5} black holes and large N unitary matrix models
• Instabilities of the Small Black Hole: a view from N=4 SYM
• The supergravity dual of 3d supersymmetric gauge theories with unquenched flavors
• Screening effects on meson masses from holography
• Holographic flavor in N=4 gauge theories in 3d from wrapped branes
• N=4 SYM on S^3 with Near Critical Chemical Potentials
• Magnetic Heisenberg-chain/pp-wave correspondence
• A Note on the String Dual of N=1 SQCD-like Theories
• Models with Quartic Potential of Dynamical SUSY Breaking in Meta-Stable Vacua
• Phase transitions in large N(c) heavy quark potentials
• Hagedorn Systems from Backreacted Finite Temperature N_f=2N_c Backgrounds
• Unquenched flavors in the Klebanov-Strassler theory
• Extending BCCNR flavored geometry to the negative coupling constant region
• Phase Structure of Beta-deformed N=4 SYM on S^3 with Chemical Potentials