The Combinatorics Seminar meets on Friday in Snow 408 from 3-4pm.
Please contact Jeremy Martin if you are interested in speaking.
Marge Bayer/Jeremy Martin
Background material for the paper Relative Stanley-Reisner theory and Upper Bound Theorems for Minkowski sums by Karim Adiprasito and Raman Sanyal [Publ. Math. IHES 124 (2016), 99-163]
Stanley's proof of the Upper Bound Conjecture for simplicial spheres
Balanced Cohen-Macaulay complexes
Cayley polytopes and Minkowski sums
Cass Sherman (Oklahoma State)
Polynomials of Stretched Littlewood-Richardson Numbers
Abstract: Littlewood-Richardson (L-R) coefficients describe multiplicities of irreducible representations in a tensor product. They depend on combinatorial parameters called weights. These can be stretched by any positive integer. For a fixed set of weights, one considers the effect of stretching on L-R numbers, i.e. the function which associates to an integer \(N\) the L-R coefficient with the weights stretched by \(N\). This function is a polynomial with many nice properties. In this talk, we will discuss these properties and their relationship to the algebraic geometry of a certain polarized moduli space \((M,L)\), connected to the L-R numbers by a famous theorem of Borel-Weil.
No seminar (Spring Break)
Simplicial and Cellular Spanning Trees
Abstract: Counting spanning trees in graphs is a classical topic, dating back at least as far as Kirchhoff's discovery of the Matrix-Tree Theorem in the 1840s. Much of the theory of tree enumeration carries over to the higher-dimensional setting, where the graph is replaced with a simplicial or CW-complex - but with a twist. I will strive to make this talk should be accessible to all graduate students.
Cumulants and moments for products of free random variables
Oral Presentation for Departmental Honors
No seminar (Stop Day)
For seminars from previous semesters, please see the KU Combinatorics Group page.
Last updated Thu 5/15/17