Matroid Chern-Schwartz-MacPherson cycles and Tutte activities
Combinatorics
2022-07-21 v2
Abstract
Lop\'ez de Medrano-Rin\'con-Shaw defined Chern-Schwartz-MacPherson cycles for an arbitrary matroid and proved by an inductive geometric argument that the unsigned degrees of these cycles agree with the coefficients of , where is the Tutte polynomial associated to . Ardila-Denham-Huh recently utilized this interpretation of these coefficients in order to demonstrate their log-concavity. In this note we provide a direct calculation of the degree of a matroid Chern-Schwartz-MacPherson cycle by taking its stable intersection with a generic tropical linear space of the appropriate codimension and showing that the weighted point count agrees with the Gioan-Las Vergnas refined activities expansion of the Tutte polynomial.
Keywords
Cite
@article{arxiv.2007.10278,
title = {Matroid Chern-Schwartz-MacPherson cycles and Tutte activities},
author = {Ahmed Umer Ashraf and Spencer Backman},
journal= {arXiv preprint arXiv:2007.10278},
year = {2022}
}