Presented By: Algebraic Geometry Seminar - Department of Mathematics
Algebraic Geometry Seminar: Curious properties of Chow rings of matroids
Shiyue Li (U. Michigan)
The Chow rings of matroids were constructed by Feichtner—Yuzvinsky as the Chow ring of smooth, but typically noncompact, toric varieties. They satisfy remarkable Hodge theoretic properties that are satisfied by a smooth projective variety. These special properties became the start of combinatorial Hodge theory, and played a key role in the resolution of the Heron-Rota-Welsh conjecture on log-concavity of characteristic polynomials of matroids, and the Dowling—Wilson top-heavy conjecture. I will survey some properties of Chow rings and K-rings of matroids, including the construction of an exceptional Hirzebruch—Riemann—Roch theorem. I will touch on some progress on open conjectures surrounding real-rootedness of Poincare polynomials of the Chow rings of matroids, and their connection to combinatorial commutative algebra.