This virtual seminar on topics that bridge combinatorics and geometry will be held on Zoom (usually) at 11:30-12:30 Eastern (Toronto) Time on the first Wednesday of every month. Complete this form to join our mailing list.
Upcoming seminars are listed below. Previous seminars are available on other tabs by year: 2024 or 2025. Some recordings are available on the YouTube channel.
Ahmed Ashraf (University of Toronto, Mississauga)
Christin Bibby (Louisiana State University, Baton Rouge)
Graham Denham (Western University, London ON)
No seminar in January 2026; will resume in February. Note the one-time change in day for February's seminar.
Luis Ferroni and Alex Fink recently introduced a polytope of all unlabeled matroids of rank r on n elements, and they showed that the vertices of this polytope come from matroids that can be characterized by maximizing a sequence of valuative invariants. In this talk, we will first sketch the background that is needed to understand their polytope and valuative invariants. We will then provide the needed characterizations of many of the matroids that Ferroni and Fink conjectured to yield vertices, we will give additional examples of such matroids, and we will mention some open problems.