Algebraic and enumerative combinatorics seminar-Christian Gaetz

Tuesday, October 15, 2024 2:00 pm - 3:00 pm EDT (GMT -04:00)

Title: Hypercube decompositions and combinatorial invariance for Kazhdan-Lusztig polynomials

Speaker: Christian Gaetz
Affiliation: UC Berkeley
Location: MC 5501

Abstract: Kazhdan-Lusztig polynomials are of foundational importance in geometric representation theory. Yet the Combinatorial Invariance Conjecture, due to Lusztig and to Dyer, suggests that they only depend on the combinatorics of Bruhat order. I'll describe joint work with Grant Barkley in which we adapt the hypercube decompositions introduced by Blundell-Buesing-Davies-Veličković-Williamson to prove this conjecture for Kazhdan-Lusztig R-polynomials in the case of elementary intervals in the symmetric group. This significantly generalizes the main previously known case of the conjecture, that of lower intervals.

There will be a pre-seminar presenting relevant background at the beginning graduate level starting at 1pm.