Unless otherwise stated, seminars
will take place in Seminar Room of the
ICMS
at
the University of Edinburgh.

Please contact the organisers Jelle
Hartong (UoE) or Bart Vlaar
(HW)
with any questions regarding the seminars.

Wednesday,
3 October 2018

ICMS Lecture Theatre (room 5.10)

14:30

Amihay Hanany
(Imperial College)

When M5 branes are placed in an A type ALE background there are tensionless strings which arise each time 2 or more M5 branes coincide. The system has no low energy Lagrangian description and new techniques need to be applied in order to figure out the relevant physics of such coincident M5 branes. The world volume theory on the M5 branes has (0,1) supersymmetry in 6 dimensions with massless vector, tensor and hyper multiplets. There are two branches on the moduli space of vacuum configurations where scalar fields in tensor and hyper multiplets receive VEVs, respectively. In this talk we will focus on the Higgs branch of the low energy theory and find new and fairly surprising results. Each time there is a new tensionless string, there is a new Higgs branch, thus the theory has a multitude of Higgs branches depending on the types of tensionless strings in the spectrum. There are two main effects: “discrete gauging” and “small instanton transitions” (when one extends beyond A type) and a need to efficiently describe the so many Higgs branches which arise. The main tool is the Coulomb branch of 3d N=4 gauge theories, which has been studied intensively by many of my collaborators.

16:00

Bart Vlaar
(Heriot-Watt)

Quantum integrability is typically underpinned by factorizability criteria (say, of a scattering process). Away from boundaries this is the Yang-Baxter equation, a cubic relation which is intimately connected to certain bialgebras known as affine quantum groups and their representations. In the presence of a boundary, a quartic relation known as the reflection equation is the natural analogue. It arises naturally in the representation theory of certain pairs (affine quantum group, coideal subalgebra). We will survey this and highlight some recent work: the classification of solutions in the case of quantum affine sl_N (joint work with V. Regelskis). We will also outline some work in progress about the axiomatic characterization and construction of so-called universal solutions (joint with R. Weston and A. Appel, respectively).

Wednesday,
17 October 2018

ICMS Lecture Theatre (room 5.10)

14:30

Jan de Boer
(University of Amsterdam)

TBA

16:00 (change of location: Seminar Room 5.02)

Marc-Antoine Fiset
(University of Oxford)

Conformal field theories with higher spin currents have been known to govern type II string dynamics in exceptional holonomy manifolds since the work of Shatashvili and Vafa. From a nonlinear sigma-model viewpoint, the reduction of holonomy yields chiral symmetries extending (1,1) supersymmetry. I will generalise this result to generic (1,0) models with Fermi superfields, appropriate in particular for heterotic compactifications. I will then comment on anomalies of these symmetries, as a first step to bridge the gap between target space geometry and abstract conformal field theory. Based on 1809.01138.

Wednesday,
31 October 2018

ICMS Seminar Room

Wednesday,
14 November 2018

ICMS Seminar Room

Wednesday,
28 November 2018

ICMS Seminar Room

Wednesday,
12 December 2018

ICMS Seminar Room