Logic Seminar

Iian SmytheUniversity of Manitoba
A descriptive approach to manifold classification

Friday, October 27, 2023 - 2:55pm
Malott 205

We describe a unified descriptive set-theoretic framework for studying the complexity of classification problems arising in geometric topology. We establish several precise complexity results, such as for the classification of surfaces up to homeomorphism, and for classes of hyperbolic manifolds up to isometry. The latter is intimately connected with the study of conjugation actions of certain Lie groups on their spaces of discrete subgroups. This work is joint with Jeffrey Bergfalk.