14:30
14:30
Understanding and mitigating the bias of Diffusion Posterior Sampling algorithm
Abstract
14:00
Mathematrix: End of term crafts
Abstract
Take a break at the end of term with some Mathematrix crafts and sweet treats! Supplies for watercolor and origami will be provided, and you are welcome to bring your own crafts.
12:00
Mathematrix: International Women in Mathematics Day
Abstract
Everyone is invited to celebrate International Women in Mathematics Day with a pizza lunch! We will be watching ‘Journeys of Women in Mathematics’, a powerful 20-minute film by the International Mathematical Union showcasing the experiences of women mathematicians worldwide. It follows three mathematicians from India, Cameroon, and Brazil from their home institutions to the (WM)² international meeting, showing their research and what it’s like to be part of the global maths community.
Algorithmic characterizations of hyperbolicity via quasigeodesics
Abstract
Gromov-hyperbolic groups are classically defined geometrically, by the negative curvature of their Cayley graphs. Interestingly, an algorithmic characterization of hyperbolicity is possible in terms of properties of the formal languages of quasigeodesics (geodesics up to bounded error) in their Cayley graphs. Holt and Rees proved, roughly speaking, that these formal languages are regular in the case of hyperbolic groups. More recently Hughes, Nairne, and Spriano established the converse. In this talk, I will discuss progress towards a conjectured strengthening of the result, where we consider context-free quasigeodesic languages. This is based on my summer project, supervised by Joseph MacManus and Davide Sprianoc
15:00
Decombinatorialisation
Abstract
15:00
Some facts about ε-harmonic maps
Abstract
The ε-energy is a regularisation of the Dirichlet energy introduced by Tobias Lamm. Like the famous Sacks-Uhlenbeck regularisation this greatly improves the existence and regularity theory. When we take the limit of a sequence of ε-harmonic maps with the parameter ε decreasing to 0 these converge, in the standard bubbling sense, to harmonic maps, which we hope to extract information about. I will talk about some recent results for these sequences, being when we might hope to have no loss of energy and no neck forming and what sort of harmonic maps we can obtain in the limit.