Academic Year 2007/2008

Unless otherwise stated, seminars will take place in 9.01 of the David Hume Tower at the University of Edinburgh.
Please contact the organisers Tim Adamo (UoE) or Richard Davison (HW) with any questions regarding the seminars.
Wednesday, 5 March 2008 at 14:30
Martin Wolf (Imperial)
Wednesday, 20 February 2008 at 14:30
Urs Schreiber (Hamburg)
Wednesday, 6 February 2008 at 14:30
Alvaro Restuccia (MPI, Potsdam)
Wednesday, 6 February 2008 at 16:00
Simon Ross (Durham)
Wednesday, 23 January 2008 at 14:30
David Berman (QMUL)
Wednesday, 9 January 2008 at 16:00
Paul Fendley (Virginia)
Wednesday, 12 December 2007
Michela Petrini (LPTHE, Jussieu)
N=1 flux vacua: geometry and non-geometry
Harvey Reall (DAMTP, Cambridge)
Black holes in string theory
Monday, 3 December 2007 at 16:15
Vladimir Kazakov (LPTHE)
Integrability and the AdS/CFT correspondence
Wednesday, 28 November 2007
Pau Figueras (Durham)
In this talk I will present the black saturn, which is a solution of Einstein's vacuum equations in five dimensions which consists of a black ring with a Myers-Perry black hole at its center. Since both black objects are rotating, this system is especially suited for studying ergosurfaces mergings analytically. It is found that for various distributions of mass and angular momenta, the ergosurfaces merge at a universal angle. This leads us to formulate a new universality conjecture. I may also discuss some possible implications in AdS/CFT.
Ezra Getzler (Imperial)
Deligne-Mumford moduli spaces for Riemann surfaces with boundary and open/closed TFT
Wednesday, 14 November 2007
Spiro Karigiannis (Oxford)
I will discuss the moduli space of G2 manifolds, including some of its special geometric structures: the superpotential, the Yukawa coupling, and the curvature of the Hitchin metric.
George Papadopoulos (KCL)
I shall review the progress that has been made the last 10 years to understand the geometry of supersymmetric backgrounds. These include extreme black holes, gravitational instantons, branes, and Calabi-Yau and hyper-Kaehler manifolds. Such manifolds solve the Killing spinor equations which include a parallel transport equation for a connection with holonomy a GL group. This arises from the supersymmetry transformation of gravitino.
Wednesday, 31 October 2007
Benjamin Doyon (Durham)
The bi-partite entanglement entropy is a quantity that says how much quantum entanglement there is between two parts (or sub-systems) of a quantum system in its ground state. Using the form factors of massive one-dimensional integrable quantum models, I will explain how to evaluate its leading terms when one of the sub-system is of large size. The leading correction is surprisingly universal, and only depends on the particle spectrum of the model. This is done using a "replica trick", where the entanglement entropy is obtained from the partition function of the quantum model on a Riemann surface with branch points. The evaluation of this partition function requires the definition of new quantum fields with special properties that are associated to these branch points, and the calculation of their form factors is done by solving a set of equations and analytic properties that generalises the usual one. This also gives the partition function on a space with conical singularities.
Anton Ilderton (Plymouth)
I will describe a new and efficient method for finding the vacua of 4D effective theories which descend from flux compactifications in string theory. These methods, which use ideas from algebraic geometry, find every stable, physical vacuum of a wide class of phenomenological models, including models with non-perturbative effects.
Joint EMPG-Geometry Seminar
Wednesday, 24 October 2007 at 16:00
Peggy Kao (ESI, Vienna)
T-duality originally arises as a symmetry of string theory which relates string theory compactified on large circles with string theory compactified on small circles. Locally the transformation rules of the low energy effective fields under T-duality are given by the well-known Buscher rules, however global issues in the presence of NS 3-form H-flux have remained obscure. Through examples in the literature, it is argued that T-duality lead to a topology change of the underlying manifold . Many open questions regarding T-duality in the presence of background fluxes remain to be answered though. In order to understand the topology change under T-duality, a systematic method has been developed by Bouwknegt, Evslin and Mathai. It was recently discovered by Gualtieri and Cavalcanti that Generalized geometry provides a natural setting to study T-duality. In this talk we will review basic settings of Generalized geometry, concepts of topological T-duality constructed by Bouwknegt, Evslin and Mathai, and how to extend T-duality in the context of Generalized geometry. In particular, we extend the results by Gualtieri and Cavalcanti of principal circle bundles to general principal torus bundles with a generalization of the Courant bracket which is invariant under T-duality transformation in the presence of non-trivial background flux. At the end we show how Lie algebroid theory can be applied to interpret our result.
Wednesday, 17 October 2007
Joan Simón (Edinburgh)
Entropy of near-extremal AdS5 black holes
Julian Sonner (DAMTP, Cambridge)
I will describe the emergence of geometric (Berry) phases in supersymmetric systems. In theories with degenerate states, non-Abelian geometric phases can arise. I show how supersymmetry helps to ensure the existence of this phenomenon by invoking the examples of systems with (2,2) and (4,4) supersymmetry. In the former, I show how instantons contribute crucially to the form of the non-Abelian phase. The latter system applies to D0-D4 brane dynamics in string theory, leading to a surprising re-interpretation of the Berry phase in terms of gravitational precession of a probe brane.
Wednesday, 3 October 2007
Marija Zamaklar (Durham)
Integrability in the AdS/CFT correspondence
Kasper Peeters (Utrecht)
Holographic mesons and Skyrmions
PhD comics take on seminars