This week



Regular Seminar Nuno Freitas (Warwick and KCL)

15:00 City U.
room C320


Polygon Seminar: Tales from the Edge

Triangular Seminar Christopher Herzog (KCL)

15:00 KCL
room K2.40

I discuss some aspects of boundary conformal field theories (bCFTs) with an emphasis on space-time dimensions greater than two. I will demonstrate that free bCFTs have a universal way of satisfying crossing symmetry constraints. I will introduce a simple class of interacting bCFTs where the interaction is restricted to the boundary. Finally, I will discuss relationships between boundary trace anomalies and boundary limits of stress-tensor correlation functions. (Tea and biscuits + wine at the end!)

Higher spin geometries

Regular Seminar Per Sundell (Andres Bello University)

13:15 KCL
room K4.31

We review the global formulation of higher spin gravity using topological field theory methods and non-commutative geometry and related recent progress in constructing micro states for black holes, domain walls and cosmologies.


On the scaling limit of the integer quantum Hall plateau transition

Regular Seminar Martin Zirnbauer (University of Cologne)

14:00 QMW
room G O Jones 610

The scaling behavior near the transition between plateaus of the integer quantum Hall effect has traditionally been interpreted on the basis of a two-parameter renormalization group flow conjectured from the non-linear sigma model of Pruisken. Yet, this scaling picture never led to any analytical understanding of the critical point. Here we propose a novel description of the critical point as Pruisken's nonlinear sigma model coupled to a maximally gauged Wess-Zumino-Witten model of level 4. This proposal explains the existing numerical data for the multifractal scaling exponents of critical wavefunctions.