Mathematics Seminar by Richard Gonzales (IHES - PUCP)

You are most cordially invited to Yeditepe Mathematics Department Seminars. The details of this week's talk are as follows. The seminar will be online via Google Meet.
 

Speaker: Richard Gonzales (IHES - PUCP)

Title: Equivariant cohomology of group embeddings

Abstract: In this talk I will describe how the symmetries of a variety (encoded via a group action) can be used to understand the geometry and topology not only of the variety itself, but also of higher structures defined on it, like vector bundles or sheaves. The study of those structures that are left invariant under the group action leads naturally to the notion of equivariant cycles and related topological invariants (e.g. Chow groups). Moreover, in many cases of interest (e.g. group embeddings or compactifications of reductive groups) these topological invariants can be read off from a suitable combinatorial object, like a graph or a fan, leading to nice combinatorial descriptions of the corresponding cohomology. In this talk I will describe how the symmetries of a variety (encoded via a group action) can be used to understand the geometry and topology not only of the variety itself, but also of higher structures defined on it, like vector bundles or sheaves. The study of those structures that are left invariant under the group action leads naturally to the notion of equivariant cycles and related topological invariants (e.g. Chow groups). Moreover, in many cases of interest (e.g. group embeddings or compactifications of reductive groups) these topological invariants can be read off from a suitable combinatorial object, like a graph or a fan, leading to nice combinatorial descriptions of the corresponding cohomology.

Date: Friday, September 19, 2025
Time: 13:00 Istanbul Time 
Place: Google Meet (link: TBA)*

Listing: https://researchseminars.org/seminar/7tepemathseminars

(*) The meet link will be available here and/or on the lıstıng website.