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CAGE: Philadelphia Area Combinatorics and Alg. Geometry Seminar

Thursday, February 14, 2019 - 3:00pm

Philippe Nadeau



University of Pennsylvania


The Peterson variety is a subvariety of the full flag variety, and as such has a cohomology class, which can be expanded in the basis of Schubert classes. The coefficients are nonnegative since they represent certain intersection numbers, but can be tricky compute with geometric methods.
Our goal is to find a combinatorial interpretation for these coefficients. In this talk, we use an algebro-combinatorial approach to give some partial answers to this problem. Schubert polynomials, reduced words of permutations and tableau combinatorics will play key roles.
Joint work with  Vasu Tewari (UPenn).