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University of York Geometry, Analysis and Mathematical Physics seminar 2024-25
All are welcome to attend the seminar, which usually takes place at 2pm on Tuesdays in the Topos during term time. (Directions to the Topos)
Autumn Semester 2024
Spring Semester 2025
| Date | Speaker | Title |
| 14 January | | |
| 21 January | | |
| 28 January | | |
| 4 February | | |
| 11 February | | |
| 18 February | Francesca Tripaldi (Leeds) | TBA |
| 25 February | | |
| 4 March | Josh Cork (Leicester) | TBA |
| 11 March | | |
| 18 March | | |
| 25 March | | |
| 1 April | | |
| 22 April | | |
| 29 April | | |
| 6 May | | |
Previous years' seminars
2023-24
2022-23
2021-22
2020-21
2019-20
Abstracts
15 October. Benoît Vicedo (York)
Title. (Higher) operations in topological and conformal QFTs from factorisation
Abstract. Prefactorisation algebras (PFAs) axiomatise the algebraic structure of observables in QFTs. In the case of locally constant PFAs, which correspond to topological QFTs, I will describe how the PFA induces a (higher) algebraic structure on the gauge invariant observables of the TQFT. This involves an ordinary associative, unital product but typically also "higher" operations known as Massey products. I will also discuss the case of holomorphic PFAs in one complex dimension, which correspond to 2d CFTs, and explain how in this setting the PFA encodes the vertex algebra structure of the CFT.
22 October. Graeme Wilkin (York)
Title. The Morse complex for semiprojective varieties
Abstract. Moduli spaces of Higgs bundles admit a natural \(\mathbb{C}^*\) action, which makes them examples of semiprojective varieties. In the first paper on the subject, Hitchin introduced the moment map associated to the action of \(S^1 \hookrightarrow \mathbb{C}^*\) and showed that this is a perfect Morse-Bott function. In this talk I will describe the cup product on the Morse complex for both this moment map as well as minus the moment map. This setup applies more generally to semiprojective varieties satisfying an additional transversality condition. I will spend some time explaining the case of rank \(2\) twisted Higgs bundles, where these constructions relate to questions from classical geometry.
5 November. Ian McIntosh (York)
Title. The geometric Toda equations for noncompact symmetric spaces
Abstract. Different forms of the Toda equations keep turning up both in surface theory and gauge theory. Everyone knows that they are really equations on something like the Cartan subgroup of a simple Lie group. While these have been well studied when the group is compact, the noncompact case has (surprisingly) not been given a general treatment. The aim of the talk is to explain a classification of these equations which fit the geometrical setting of minimal surfaces in noncompact symmetric spaces, and also discuss when methods from gauge theory (especially stability ideas) can be applied to provide spaces of solutions.
19 November. Inder Kaur (Glasgow)
Title. TBA
Abstract. TBA
26 November. Martin Kerin (Durham)
Title. TBA
Abstract. TBA
3 December. Ben Lambert (Leeds)
Title. TBA
Abstract. TBA
18 February. Francesca Tripaldi (Leeds)
Title. TBA
Abstract. TBA
4 March. Josh Cork (Leicester)
Title. TBA
Abstract. TBA
Last updated 22 October, 2024
