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, 17 Feb 2026

14:00 - 15:00
C3

Approximating Processes on Complex Networks

George Cantwell
(University of Cambridge)
Abstract
Graphs are an attractive formalism because, despite over-simplification, they seem capable of representing the rich structure we see in complex dynamical systems. 
Mean-field style approximations can be highly effective at describing equilibrium systems. In this talk, we will begin by reviewing such methods and showing how to make systematic corrections to them via spatial expansions. Adapting the methods for dynamic systems is an ongoing project. Through two simple case studies -- the random walk and the SIS model -- we make a start on this. In both case studies non-trivial predictions are made.



 

Tue, 24 Feb 2026

14:00 - 15:00
C3

Spectral coarse graining and rescaling for preserving structural and dynamical properties in graphs

Marwin Schmidt
(UCL)
Abstract

We introduce a graph renormalization procedure based on the coarse-grained Laplacian, which generates reduced-complexity representations across scales. This method retains both dynamics and large-scale topological structures, while reducing redundant information, facilitating the analysis of large graphs by decreasing the number of vertices. Applied to graphs derived from electroencephalogram recordings of human brain activity, our approach reveals collective behavior emerging from neuronal interactions, such as coordinated neuronal activity. Additionally, it shows dynamic reorganization of brain activity across scales, with more generalized patterns during rest and more specialized and scale-invariant activity in the occipital lobe during attention.

Tue, 03 Mar 2026
14:00
C3

TBA

Dr. Jacob Calvert
((Mathematical Institute University of Oxford))
Tue, 10 Mar 2026
14:00
C3

TBA

Márton Pósfai
(Central European University)