English

Sigma-invariants and tropical varieties

Algebraic Geometry 2021-08-10 v2 Group Theory Geometric Topology

Abstract

The Bieri-Neumann-Strebel-Renz invariants Σq(X,Z)H1(X,R)\Sigma^q(X,\mathbb{Z})\subset H^1(X,\mathbb{R}) of a connected, finite-type CW-complex XX are the vanishing loci for Novikov-Sikorav homology in degrees up to qq, while the characteristic varieties Vq(X)H1(X,C×)\mathcal{V}^q(X) \subset H^1(X,\mathbb{C}^{\times}) are the nonvanishing loci for homology with coefficients in rank 1 local systems in degree qq. We show that each BNSR invariant Σq(X,Z)\Sigma^q(X,\mathbb{Z}) is contained in the complement of the tropical variety associated to the algebraic variety Vq(X)\mathcal{V}^{\le q}(X), and provide applications to several classes of groups and spaces.

Keywords

Cite

@article{arxiv.2010.07499,
  title  = {Sigma-invariants and tropical varieties},
  author = {Alexander I. Suciu},
  journal= {arXiv preprint arXiv:2010.07499},
  year   = {2021}
}

Comments

30 pages; accepted for publication in Mathematische Annalen

R2 v1 2026-06-23T19:21:51.174Z