English

Free inverse monoids are not $FP_2$

Group Theory 2020-02-19 v1 Algebraic Topology Rings and Algebras

Abstract

We give a topological proof that a free inverse monoid on one or more generators is neither of type left-FP2FP_2 nor right-FP2FP_2. This strengthens a classical result of Schein that such monoids are not finitely presented as monoids.

Keywords

Cite

@article{arxiv.2002.07690,
  title  = {Free inverse monoids are not $FP_2$},
  author = {Robert D. Gray and Benjamin Steinberg},
  journal= {arXiv preprint arXiv:2002.07690},
  year   = {2020}
}

Comments

5 pages, 1 figure, This article was originally part of our paper arXiv:1805.03413, and has now been extracted as this short note

R2 v1 2026-06-23T13:45:37.338Z