English

Compact inverse categories

Category Theory 2019-06-12 v1

Abstract

The Ehresmann-Schein-Nambooripad theorem gives a structure theorem for inverse monoids: they are inductive groupoids. A particularly nice case due to Jarek is that commutative inverse monoids become semilattices of abelian groups. It has also been categorified by DeWolf-Pronk to a structure theorem for inverse categories as locally complete inductive groupoids. We show that in the case of compact inverse categories, this takes the particularly nice form of a semilattice of compact groupoids. Moreover, one-object compact inverse categories are exactly commutative inverse monoids. Compact groupoids, in turn, are determined in particularly simple terms of 3-cocycles by Baez-Lauda.

Keywords

Cite

@article{arxiv.1906.04248,
  title  = {Compact inverse categories},
  author = {Robin Cockett and Chris Heunen},
  journal= {arXiv preprint arXiv:1906.04248},
  year   = {2019}
}

Comments

15 pages

R2 v1 2026-06-23T09:49:26.758Z