Quasi-Isometry Invariance of discrete Higher Filling Functions
Group Theory
2026-03-10 v2 Metric Geometry
Abstract
We prove that homological filling functions over a ring equipped with the discrete norm are quasi-isometry invariants for all groups of type . This confirms a conjecture of Bader-Kropholler-Vankov in the case of discrete norms. The proof uses a technique of equipping free chain complexes with a geometric structure, allowing for analogues of cellular constructions in the purely algebraic setting. As a further application we prove quasi-isometry invariance for a weighted version of integral and discrete filling functions originally introduced in the study of the rapid decay property.
Keywords
Cite
@article{arxiv.2601.15140,
title = {Quasi-Isometry Invariance of discrete Higher Filling Functions},
author = {Jannis Weis},
journal= {arXiv preprint arXiv:2601.15140},
year = {2026}
}
Comments
21 pages; added a section giving a new proof of quasi-isometry invariance of cohomology with coefficients in the group ring