English

Special cases on the relative rank of G-equivariant functions over an infinite G-set

Group Theory 2024-07-09 v1

Abstract

Given the action of a group GG on a set X X , the set of G G -equivariant functions, those that commute with the action, i.e., f(gx)=gf(x) f(g \cdot x) = g \cdot f(x) for all xX x \in X , gG g \in G , forms a monoid under function composition. It is known that when a finite group G G acts on a finite set X X , a finite number of elements in this monoid are sufficient to generate it along with its group of units. The minimum number of elements required to generate the monoid is called the relative rank. This paper presents two particular cases where G G is a finite group, X X is an infinite set, and the relative rank of the monoid of G G -equivariant functions is finite; moreover, we compute it.

Keywords

Cite

@article{arxiv.2407.05939,
  title  = {Special cases on the relative rank of G-equivariant functions over an infinite G-set},
  author = {Ramón H Ruiz-Medina},
  journal= {arXiv preprint arXiv:2407.05939},
  year   = {2024}
}