English

Tautological classes of matroids

Combinatorics 2023-04-17 v4 Algebraic Geometry

Abstract

We introduce certain torus-equivariant classes on permutohedral varieties which we call "tautological classes of matroids" as a new geometric framework for studying matroids. Using this framework, we unify and extend many recent developments in matroid theory arising from its interaction with algebraic geometry. We achieve this by establishing a Chow-theoretic description and a log-concavity property for a 4-variable transformation of the Tutte polynomial, and by establishing an exceptional Hirzebruch-Riemann-Roch-type formula for permutohedral varieties that translates between K-theory and Chow theory.

Keywords

Cite

@article{arxiv.2103.08021,
  title  = {Tautological classes of matroids},
  author = {Andrew Berget and Christopher Eur and Hunter Spink and Dennis Tseng},
  journal= {arXiv preprint arXiv:2103.08021},
  year   = {2023}
}

Comments

71 pages; comments welcome. v4: minor edits. To appear in Invent. Math

R2 v1 2026-06-24T00:08:16.131Z