English

Some results in constructive semigroup theory

Group Theory 2021-09-07 v2 Logic

Abstract

We give a constructive treatment of some basic concepts and results in semigroup theory. Focusing on semigroups equipped with an apartness relation, we give analogues, from the point of view of apartness, of several classical constructions and results, including transitive closure and congruence closure, free semigroups, periodicity, Rees factors, and Green's relations.

Keywords

Cite

@article{arxiv.2103.07105,
  title  = {Some results in constructive semigroup theory},
  author = {Erik Darpö and Melanija Mitrović},
  journal= {arXiv preprint arXiv:2103.07105},
  year   = {2021}
}

Comments

V2: Major re-write of Section 3, due to an error in v1: Proposition 3.11. Other minor updates. 33 pages

R2 v1 2026-06-24T00:02:45.144Z