Triangle Seminars

Week of 28 Nov 2016 - 4 Dec 2016

Wednesday, 30 Nov 2016

AdS4 black holes and 3d gauge theories
๐Ÿ“ London
Alberto Zaffaroni (Milan Bicocca)
Venue: KCL ยท Room: G01 Norfolk Building ยท Time: 13:15 ยท Type: Regular Seminar
Abstract:
One of the great success of string theory is the microscopical explanation of the entropy of a class of asymptotically flat black holes.
Much less is known about asymptotically AdS black holes in four dimensions or higher. In this talk I explain how to derive the entropy of a class of asymptotically AdS supersymmetric black holes in four dimensions using holography. The counting of black hole micro-states is related to a counting of states in the dual 3d gauge theory which can be explicitly
performed using localization.
Posted by: KCL
Hilbert Series and aspects of the moduli space of instantons on CP2
Alessandro Pini (Oviedo U.)
Venue: QMW ยท Room: G.O. Jones 610 ยท Time: 14:00 ยท Type: Regular Seminar
Abstract:
In the first part of the talk I give an introduction to the computational tool called "Hilbert Series" (HS). I analyze how it can be employed for the characterization of the moduli space of vacua of a QFT and of the moduli space of instantons. Then, in the second part of the talk, I discuss the moduli space of (framed) self-dual instantons on CP^2. These are described by an ADHM-like construction which allows to compute the Hilbert Series of the moduli space. The latter has been found to be blind to certain compact directions. I probe these directions, finding them to correspond to a Grassmanian, upon considering appropriate ungaugings. Moreover I discuss the ADHM-like construction of instantons on CP^2/Z_n as well as compute its Hilbert series. As in the unorbifolded case, these turn out to coincide with those for instantons on C^2/Z_n. This talk is mainly based on https://arxiv.org/abs/1502.07876 .
Posted by: QMW

Thursday, 1 Dec 2016

Localised Black Holes and Precision Holography
Jorge Santos (Cambridge)
Venue: IC ยท Room: H503 ยท Time: 13:00 ยท Type: Regular Seminar
Abstract:
We numerically construct asymptotically global AdS_5xS^5 black holes that are localised on the S^5. These are solutions to type IIB supergravity with S^8horizon topology that dominate the microcanonical ensemble at small energies. At higher energies, there is a first-order phase transition to AdS_5-Schwarzschild x S^5. By the Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence, this transition is dual to spontaneously breaking the SO(6) R-symmetry of N=4 supersymmetric Yang-Mills down to SO(5). We extrapolate the location of this phase transition and compute the expectation value of a scalar operator in the low energy phase. In addition, we discuss the construction of localised black holes in type IIA, which are dual (via T-duality) to the low temperature phase of thermal 1+1 dimensional supersymmetric Yang-Mills theory on a circle.
Posted by: IC

Week of 28 Nov 2016 - 4 Dec 2016