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)
Computing linear extensions and order polynomials of posets is in general a hard problem with no explicit formulas and nice structure and properties. When the poset is a Young diagram of a straight shape, the number of linear extensions is given by the hook-lnegth formula, yet the corresponding number of plane partitions (order polynomial of that poset) does not have a product formula. In the absence of such nice formulas we will show a general approach to proving that the order polynomials of posets corresponding to skew Young diagrams have positive coefficients. We will also discuss some applications to matroids. Joint work with Luis Ferroni and Alejandro Morales.