Glueball Masses from Linearly Confining Supergravity

Mass spectrum of 0++ glueballs is produced using a dual supergravity theory we proposed for pure N=1 SU(N) gauge theory in four dimensions in the large N limit in the IR. The glueball states are expressed in terms of Whittaker functions. The spectrum is discrete and a function whose roots give the masses is written. The ratios of the masses are independent of the parameters of the theory and comparison to recent non-supersymmetric large N lattice QCD data available for the lowest three states shows agreement to within five percent.Comment: 11 page

A Relation Between Gravity in (3+1)(3+1)--Dimensions and Pontrjagin Topological Invariant

A relation between the MacDowell-Mansouri theory of gravity and the Pontrjagin toplogical invariant in $(3+1)$ dimensions is discussed. This relation may be of especial interest in the quest of finding a mechanism to go from non-dynamical to dynamical gravity.Comment: 9 pages, Te

Wilson-t'Hooft Loops in Finite-Temperature Non-commutative Dipole Field Theory from Dual Supergravity

We first study the temporal Wilson loop in the finite-temperature non-commutative dipole field theory from the string/gauge correspondence. The associated dual supergravity background is constructed from the near-horizon geometry of near-extremal D-branes, after applying T-duality and smeared twist. We investigate the string configuration therein and find that while the temperature produces a maximum distance $L_{max}$ in the interquark distance the dipole in there could produce a minimum distance $L_{min}$. The quark boundary pair therefore could be found only if their distance is between $L_{min}$ and $L_{max}$. We also show that, beyond a critical temperature the quark pair becomes totally free due to screening by thermal bath. We next study the spatial Wilson loop and find the confining nature in the zero temperature 3D and 4D non-supersymmetry dipole gauge theory. The string tension of the linear confinement potential is obtained and found to be a decreasing function of the dipole field. We also investigate the associated t'Hooft loop and determine the corresponding monopole anti-monopole potential. The conventional screening of magnetic charge which indicates the confinement of the electric charge is replaced by a strong repulsive however. Finally, we show that the dual string which is rotating along the dipole deformed $S^5$ will behave as a static one without dipole field, which has no minimum distance and has larger energy than a static one with dipole field. We discuss the phase transition between these string solutions.Comment: Latex, 22 pages, 8 figures, add several comment

A Holographic Prediction of the Deconfinement Temperature

We argue that deconfinement in AdS/QCD models occurs via a first order Hawking-Page type phase transition between a low temperature thermal AdS space and a high temperature black hole. Such a result is consistent with the expected temperature independence, to leading order in 1/N_c, of the meson spectrum and spatial Wilson loops below the deconfinement temperature. As a byproduct, we obtain model dependent deconfinement temperatures T_c in the hard and soft wall models of AdS/QCD. Our result for T_c in the soft wall model is close to a recent lattice prediction.Comment: 4 pages, 1 figure; v2 ref added, minor changes; v3 refs added, discussion modified, to appear in PR

Holographic Derivation of Entanglement Entropy from AdS/CFT

A holographic derivation of the entanglement entropy in quantum (conformal) field theories is proposed from AdS/CFT correspondence. We argue that the entanglement entropy in d+1 dimensional conformal field theories can be obtained from the area of d dimensional minimal surfaces in AdS_{d+2}, analogous to the Bekenstein-Hawking formula for black hole entropy. We show that our proposal perfectly reproduces the correct entanglement entropy in 2D CFT when applied to AdS_3. We also compare the entropy computed in AdS_5 \times S^5 with that of the free N=4 super Yang-Mills.Comment: 5 pages, 3 figures, Revtex, references adde

Holographic Duals of Long Open Strings

We study the holographic map between long open strings, which stretch between D-branes separated in the bulk space-time, and operators in the dual boundary theory. We focus on a generalization of the Sakai-Sugimoto holographic model of QCD, where the simplest chiral condensate involves an operator of this type. Its expectation value is dominated by a semi-classical string worldsheet, as for Wilson loops. We also discuss the deformation of the model by this operator, and in particular its effect on the meson spectrum. This deformation can be thought of as a generalization of a quark mass term to strong coupling. It leads to the first top-down holographic model of QCD with a non-Abelian chiral symmetry which is both spontaneously and explicitly broken, as in QCD. Other examples we study include half-supersymmetric open Wilson lines, and systems of D-branes ending on NS5-branes, which can be analyzed using worldsheet methods.Comment: 35 pages, 4 figures, harvmac. v2: added reference

AdS/CFT and large-N volume independence

We study the Eguchi-Kawai reduction in the strong-coupling domain of gauge theories via the gravity dual of N=4 super-Yang-Mills on R^3xS^1. We show that D-branes geometrize volume independence in the center-symmetric vacuum and give supergravity predictions for the range of validity of reduced large-N models at strong coupling.Comment: 4 pages, 2 figures; references and comments adde

P-Wave Holographic Insulator/Superconductor Phase Transition

Using a five dimensional AdS soliton in an Einstein-Yang-Mills theory with SU(2) gauge group we study p-wave holographic insulator/superconductor phase transition. To explore the phase structure of the model we consider the system in the probe limit as well as fully back reacted solutions. We will also study zero temperature limit of the p-wave holographic superconductor in four dimensions.Comment: Latex,18 pages,7 figures, v2: Typos correction, v3: minor changes added, and clarifications mad

Topological Charge Membranes in 2D and 4D Gauge Theory

Local topological charge structure in the 2D CP(N-1) sigma models is studied using the overlap Dirac operator. Long-range coherence of topological charge along locally 1D regions in 2D space-time is observed. We discuss the connection between these results and the recent discovery of coherent 3D sheets of topological charge in 4D QCD. In both cases, coherent regions of topological charge form along surfaces of approximmate codimension 1.Comment: Lattice2004(topology

Thermodynamic Instability of Black Holes of Third Order Lovelock Gravity

In this paper, we compute the mass and the temperature of the uncharged black holes of third order Lovelock gravity and compute the entropy through the use of first law of thermodynamics. We perform a stability analysis by studying the curves of temperature versus the mass parameter, and find that there exists an intermediate thermodynamically unstable phase for black holes with hyperbolic horizon. The existence of this unstable phase for the uncharged topological black holes of third order Lovelock gravity does not occur in the lower order Lovelock gravity. We also perform a stability analysis for a spherical, 7-dimensional black hole of Lovelock gravity and find that while these kinds of black holes for small values of Lovelock coefficients have an intermediate unstable phase, they are stable for large values of Lovelock coefficients. We also find that there exists an intermediate unstable phase for these black holes in higher dimensions. This stability analysis shows that the thermodynamic stability of black holes with curved horizons is not a robust feature of all the generalized theories of gravity.Comment: 16 pages, 8 figure