Please note that the list below only shows forthcoming events, which may not include regular events that have not yet been entered for the forthcoming term. Please see the past events page for a list of all seminar series that the department has on offer.

 

Past events in this series


Tue, 10 Mar 2026
13:00
L2

Hodge Structures of Complex Multiplication Type from Rational Conformal Field Theories

Pyry Kuusela,
(Sheffield)
Abstract

Gukov and Vafa have proposed that a conformal field theory describing a string compactification on a manifold is rational (an RCFT) if and only if the manifold admits complex multiplication (CM). We investigate and extend the Gukov-Vafa proposal by constructing Hodge structures of CM type using only RCFT data, without reference to a geometric interpretation. 

We use the chiral and boundary states of the RCFT to construct the complex and rational vector spaces underlying the Hodge structure. Using the known notion of Galois symmetry of RCFTs and some elementary Galois theory, we are able to show that these Hodge structures are of CM-type, subject to some technical assumptions that can be verified explicitly for large classes of theories, including those without known geometric interpretation. We also discuss briefly the relation of complex multiplication to arithmetic geometry.

This talk is based on arXiv:2510.25708 with H. Jockers and M. Sarve.

Tue, 05 May 2026
13:00
L2

The Bootstrap Siege of M-theory

Andrea Guerrieri
(City University )
Abstract
In recent years, analytic and numerical Bootstrap methods have emerged as powerful tools to probe non-perturbative aspects of quantum field theory and quantum gravity. In this talk I will discuss the nonperturbative S-matrix Bootstrap approach to scattering amplitudes in maximal supergravity. After a brief overview of the method, I will review earlier results obtained in this framework, including bounds on the Wilson coefficient of the R^4 operator in D=9,10,11, and the observation that string and M-theory amplitudes appear to lie on the boundary of the allowed bootstrap region. I will then present preliminary results for the higher dimensional corrections like the D^4 R^4 interaction in eleven dimensions and show how the resulting constraints on the non-perturbative M-theory scattering amplitude match expectations from string/M-theory.