# Balasubramanian, Ross ## The dual of nothing \[Links: [arXiv](https://arxiv.org/abs/), [PDF](https://arxiv.org/pdf/.pdf)\] \[Abstract: We consider ''[[0168 Bubble of nothing|bubbles of nothing]]'' constructed by analytically continuing black hole solutions in Anti-de Sitter space. These provide interesting examples of smooth time-dependent backgrounds which can be studied through the [[0001 AdS-CFT|AdS/CFT]] correspondence. Our examples include bubbles constructed from Schwarzschild-AdS, Kerr-AdS and Reissner-Nordstrom AdS. The Schwarzschild bubble is dual to Yang-Mills theory on three dimensional de Sitter space times a circle. We construct the boundary stress tensor of the bubble spacetime and relate it to the properties of field theory on de Sitter.\] # Bousso (Oct) ## Light-sheets and Bekenstein's bound \[Links: [arXiv](https://arxiv.org/abs/hep-th/0210295), [PDF](https://arxiv.org/pdf/hep-th/0210295.pdf)\] \[Abstract: \] ## Summary - shows that [[0171 Covariant entropy bound|Bousso bound]] implies a tight version of the [[0418 Bekenstein bound]] # Dias, Lemos ## Pair of accelerated black holes in an anti-de Sitter background: the AdS C-metric \[Links: [arXiv](https://arxiv.org/abs/hep-th/0210065), [PDF](https://arxiv.org/pdf/hep-th/0210065.pdf)\] \[Abstract: The anti-de Sitter [[0336 C-metric|C-metric]] (AdS C-metric) is characterized by a quite interesting new feature when compared with the C-metric in flat or de Sitter backgrounds. Indeed, contrarily to what happens in these two last exact solutions, the AdS C-metric only describes a pair of accelerated black holes if the acceleration parameter satisfies $A>1/L$, where $L$ is the cosmological length. The two black holes cannot interact gravitationally and their acceleration is totally provided by the pressure exerted by a strut that pushes the black holes apart. Our analysis is based on the study of the causal structure, on the description of the solution in the AdS 4-hyperboloid in a 5D Minkowski embedding spacetime, and on the physics of the strut. We also analyze the cases $A=1/L$ and $A<1/L$ that represent a single accelerated black hole in the AdS background.\] # Fuchs, Runkel, Schweigert ## TFT construction of RCFT correlators I: Partition functions \[Links: [arXiv](https://arxiv.org/abs/hep-th/0204148), [PDF](https://arxiv.org/pdf/hep-th/0204148)\] \[Abstract: We formulate rational conformal field theory in terms of a symmetric special Frobenius algebra $A$ and its representations. $A$ is an algebra in the modular tensor category of [[0602 Moore-Seiberg construction|Moore-Seiberg]] data of the underlying chiral CFT. The multiplication on $A$ corresponds to the OPE of boundary fields for a single boundary condition. General boundary conditions are $A$-modules, and (generalised) defect lines are $A$-$A$-bimodules. The relation with three-dimensional TFT is used to express CFT data, like structure constants or torus and annulus coefficients, as invariants of links in three-manifolds. We compute explicitly the ordinary and twisted partition functions on the torus and the annulus partition functions. We prove that they satisfy consistency conditions, like modular invariance and NIM-rep properties. We suggest that our results can be interpreted in terms of non-commutative geometry over the modular tensor category of Moore-Seiberg data.\] # Fukuma, Matsuura, Sakai ## Holographic Renormalization Group \[Links: [arXiv](https://arxiv.org/abs/hep-th/0212314), [PDF](https://arxiv.org/pdf/hep-th/0212314.pdf)\] \[Abstract: \] # Gauntlett, Gutowski, Hull, Pakis, Reall ## All supersymmetric solutions of minimal supergravity in five dimensions \[Links: [arXiv](https://arxiv.org/abs/hep-th/0209114), [PDF](https://arxiv.org/pdf/hep-th/0209114.pdf)\] \[Abstract: All purely bosonic supersymmetric solutions of minimal supergravity in five dimensions are classified. The solutions preserve either one half or all of the supersymmetry. Explicit examples of new solutions are given, including a large family of plane-fronted waves and a maximally supersymmetric analogue of the Gödel universe which lifts to a solution of eleven dimensional supergravity that preserves 20 supersymmetries.\] ## Setup - bosonic action: $S=\frac{1}{4 \pi G} \int\left(-\frac{1}{4} R * 1-\frac{1}{2} F \wedge * F-\frac{2}{3 \sqrt{3}} F \wedge F \wedge A\right)$ # Gibbons, Hartnoll, Pope ## Bohm and Einstein-Sasaki metrics, BHs and cosmological event horizons \[Links: [arXiv](https://arxiv.org/abs/hep-th/0208031), [PDF](https://arxiv.org/pdf/hep-th/0208031.pdf)\] \[Abstract: \] ## Summary - *argues* (with proofs in some cases) that all [[0427 Bohm metrics]] have negative Lichnerowicz modes - *deduces* that BHs with the round sphere replaced with [[0427 Bohm metrics]] are [[0339 Stability of GR solutions|unstable]] # Grumiller, Kummer, Vassilevich ## Dilaton gravity in 2D \[Links: [arXiv](https://arxiv.org/abs/hep-th/0204253), [PDF](https://arxiv.org/pdf/hep-th/0204253.pdf)\] \[Abstract: \] ## Refs - deals with the [[vapour_nonmin]] - parent [[0241 2D models of 4D physics]] # Hikida ## Liouville Field Theory on an Unoriented Surface \[Links: [arXiv](https://arxiv.org/abs/hep-th/0210305), [PDF](https://arxiv.org/pdf/hep-th/0210305)\] \[Abstract: [[0562 Liouville theory|Liouville field theory]] on an [[0620 Non-orientable CFT|unoriented]] surface is investigated, in particular, the one point function on a $RP^2$ is calculated. The constraint of the one point function is obtained by using the crossing symmetry of the two point function. There are many solutions of the constraint and we can choose one of them by considering the modular bootstrap.\] # Klebanov, Polyakov ## AdS Dual of the Critical $O(N)$ Vector Model \[Links: [arXiv](https://arxiv.org/abs/hep-th/0210114), [PDF](https://arxiv.org/pdf/hep-th/0210114)\] \[Abstract: We suggest a general relation between theories of infinite number of [[0421 Higher-spin gravity|higher-spin massless gauge fields]] in AdS$_{d+1}$ and large $N$ conformal theories in $d$ dimensions containing $N$-component vector fields. In particular, we propose that the singlet sector of the well-known critical 3-d $O(N)$ model with the $(\phi^a \phi^a)^2$ interaction is dual, in the large $N$ limit, to the minimal bosonic theory in AdS$_4$ containing [[0588 Higher-spin fields|massless gauge fields of even spin]].\] # Kol ## Topology change in General Relativity and the black-hole black-string transition \[Links: [arXiv](https://arxiv.org/abs/hep-th/0206220), [PDF](https://arxiv.org/pdf/hep-th/0206220.pdf)\] \[Abstract: \] # Loll ## A discrete history of the Lorentzian path integral \[Links: [arXiv](https://arxiv.org/abs/hep-th/0212340), [PDF](https://arxiv.org/pdf/hep-th/0212340.pdf)\] \[Abstract: \] ## Summary - non-perturbative Lorentzian path integral - ==regularised, discrete== - solves the problems of 1. well-defined Wick rotation 2. coordinate invariant cutoff 3. convergent sum over geometries - explicit example of - inequivalence of Euclidean and Lorentzian path integrals - non-perturbative mechanism of cancelation of the conformal factor - **causality** can act as an effective regulator of quantum geometry # Page, Surya, Woolgar ## Positive Mass from Holographic Causality \[Links: [PRL](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.89.121301)\] \[Abstract: \] ## Summary - uses [[0091 Boundary causality]] to show [[0116 Positive energy theorem]] # Policastro, Son, Starinets ## From AdS/CFT correspondence to hydrodynamics \[Links: [arXiv](https://arxiv.org/abs/hep-th/0205052), [PDF](https://arxiv.org/pdf/hep-th/0205052.pdf)\] \[Abstract: We compute the correlation functions of R-charge currents and components of the stress-energy tensor in the strongly coupled large-N finite-temperature [[0155 N=4 SYM|N=4 supersymmetric Yang-Mills theory]], following a recently formulated Minkowskian AdS/CFT prescription. We observe that in the long-distance, low-frequency limit, such correlators have the form dictated by hydrodynamics. We deduce from the calculations the R-charge diffusion constant and the shear viscosity. The value for the latter is in agreement with an earlier calculation based on the Kubo formula and absorption by black branes.\] ## Refs - twin paper [[2002#Son, Starinets]] # Sezgin, Sundell ## Massless Higher Spins and Holography \[Links: [arXiv](https://arxiv.org/abs/hep-th/0205131), [PDF](https://arxiv.org/pdf/hep-th/0205131)\] \[Abstract: We treat free large $N$ superconformal field theories as holographic duals of [[0588 Higher-spin fields|higher spin (HS) gauge theories]] expanded around AdS spacetime with radius $R$. The HS gauge theories contain massless and light massive AdS fields. The HS current correlators are written in a crossing symmetric form including only exchange of other HS currents. This and other arguments point to the existence of a consistent truncation to massless HS fields. A survey of massless HS theories with 32 supersymmetries in $D=4,5,7$ (where the 7D results are new) is given and the corresponding composite operators are discussed. In the case of AdS$_4$, the cubic couplings of a minimal bosonic massless HS gauge theory are described. We examine high energy/small tension limits giving rise to massless HS fields in the Type IIB string on AdS$_5 \times S^5$ and M theory on AdS$_{4/7} \times S^{7/4}$. We discuss breaking of HS symmetries to the symmetries of ordinary supergravity, and a particularly natural Higgs mechanism in AdS$_5 \times S^5$ and AdS$_4 \times S^7$ where the HS symmetry is broken by finite $g_{YM}$. In AdS$_5 \times S^5$ it is shown that the supermultiplets of the leading Regge trajectory cross over into the massless HS spectrum. We propose that $g_{YM}=0$ corresponds to a critical string tension of order $1/R^2$ and a finite string coupling of order $1/N$. In AdS$_7 \times S^4$ we give a rotating membrane solution coupling to the massless HS currents, and describe these as limits of Wilson surfaces in the $A_{N-1}(2,0)$ SCFT, expandable in terms of operators with anomalous dimensions that are asymptotically small for large spin. The minimal energy configurations have semi-classical energy $E=s$ for all $s$ and the geometry of infinitely stretched strings with energy and spin density concentrated at the endpoints.\] # Son, Starinets ## Minkowski-space correlators in AdS/CFT correspondence: recipe and applications \[Links: [arXiv](https://arxiv.org/abs/hep-th/0205051), [PDF](https://arxiv.org/pdf/hep-th/0205051.pdf)\] \[Abstract: We formulate a prescription for computing Minkowski-space correlators from [[0001 AdS-CFT|AdS/CFT correspondence]]. This prescription is shown to give the correct retarded propagators at zero temperature in four dimensions, as well as at finite temperature in the two-dimensional conformal field theory dual to the [[0086 Banados-Teitelboim-Zanelli black hole|BTZ]] black hole. Using the prescription, we calculate the Chern-Simons diffusion constant of the finite-temperature $N=4$ supersymmetric Yang-Mills theory in the strong coupling limit. We explain why the [[0325 Quasi-normal modes|quasinormal]] frequencies of the asymptotically AdS background correspond to the poles of the [[0473 Retarded Green's function|retarded Green's function]] of the boundary conformal field theory.\] ## Refs - proof by [[2009#Iqbal, Liu]] - twin paper [[2002#Policastro, Son, Starinets]] ## Summary - a recipe for computing the [[0473 Retarded Green's function|retarded Green's function]] (and hence all 2-point functions) but not for higher points - relates the pole of Green function to [[0325 Quasi-normal modes|QNM]] frequencies ## Analytic continuation - at Matsubara frequencies, the Green's function reduces to the Euclidean one: $G^{R}(2 \pi i T n, \boldsymbol{k})=-G^{E}(2 \pi T n, \boldsymbol{k})$ (similarly for the advanced Green's function at *negative* Matsubara frequencies)