Events in the Department of Mathematics
The department maintains a regular series of research seminars, details of which can be found on our main department page.
|Date||Speaker||Titles and abstracts|
|6th October 2020||Rob Noble, (City, University of London)||Characterising and forecasting tumour evolution|
|13th October 2020||Wolfram Mobius (Exeter)|
Two layers of chance associated with spatially expanding populations: How demographic noise and environmental heterogeneity shape the evolutionary path of a population
In nature, populations expand into new habitat at different spatial and temporal scales, from bacterial cells forming a colony all the way to invasive species colonising new geographical regions. The expansion process can thereby affect the evolutionary path of the growing population, a topic that has gathered much interest recently. The effects of environmental heterogeneity on the evolutionary dynamics of such range expansions remains poorly understood so far - not least due to the large variety of environmental heterogeneity found in nature. To understand the effects of this heterogeneity, we use a combination of simulations, analytical theory, and experiments with microbial model systems.In a bottom-up approach we are seeking to first understand the effects of isolated inhomogeneities and then describe the evolution in complex heterogeneous environments. Specifically, we first consider the effects of isolated obstacles and hotspots as well as bumps in an otherwise flat habitat. The former two are regions which hinder and accelerate the invasion, respectively. We find that those structures have characteristic consequences for neutral genetic diversity (the distribution of individuals that are genetically different, but do not have a selective advantage or disadvantage). We observe an additional layer of ‘survival of the luckiest’ – complementary to, yet qualitatively different from, founder effects occurring in the presen
|20th October 2020||Alexander Kasprzyk (Nottingham)|
Exploring the landscape of Fano classification
Our understanding of Fano classification via Mirror Symmetry has grown considerably over the past decade. Although still very much conjectural, we now have systematic ways to begin exploring what this classification might eventually look like. I will describe recent work, joint with Giuseppe Pitton, Liana Heuberger, and others, which builds upon the existing classifications of Fano polytopes in dimensions 3 and 4 and begins to systematically construct examples against which our conjectures and intuition can be tested. This is very-much work-in-progress.
|27th October 2020||Bernd Schroers (Edinburgh)||Magnetic Skyrmions: Integrable Models and their Applications|
Chiral magnetic skyrmions are topological solitons in two-dimensional magnetic systems which are stabilised by the so-called Dzyaloshinskii-Moriya interaction (DMI). For each DMI term, there is a model for magnetic skyrmions which is integrable and where solitons can be written down explicitly in terms of holomorphic functions. In this talk I will explain the integrable models and how they can be used to obtain magnetic skyrmions in generic (non-integrable) models. This approach reveals a remarkable diversity of magnetic skyrmions and suggests a new way of interpreting their structure. In particular, configurations with positive topological charge are best understood in terms of one-dimensional domain walls carrying chiral kinks. I will explain this point of view, and speculate about possible generalisations. The first part of the talk is based on arXiv:1905.06285, and the second part on joint work with Vlad Kuchkin, Bruno Barton-Singer, Filipp Rybakov, Stefan Bluegel and Nikolai Kiselev.
|10th November 2020||Marika Taylor (Southampton)||Spacetime reconstruction and quantum error correction codes|
The holographic paradigm states that spacetime can be reconstructed from the data of a quantum field theory in one less dimension. In recent years there has been considerable interest in the relationship between spacetime reconstruction and quantum error correction. Much of the literature has been focussed on low dimensional spacetimes e.g. reconstruction of the hyperbolic plane. In this talk we will explore the relationship between certain classes of quantum error correction codes and reconstruction of general dimensional spacetimes via cellulations.
|17th November 2020||Roberto Tateo (Torino)|
|24th November 2020||Jacopo Viti (ENS)|
|1st December 2020||Paul Bushby (Newcastle)|
|8th December 2020||Cesare Guilio Ardito (City)|
Workshops and conferences
Recent conferences and workshops organised by the centre soon to be published.