The "spread" of Thompson's group $F$
Abstract
Recall that a group is said to be -generated if every non-trivial element has a co-generator in (i.e., an element which together with generates ). Thompson's group was proved to be -generated by Donoven and Harper in 2019. It was the first example of an infinite finitely presented non-cyclic -generated group. In 2022, Bleak, Harper and Skipper proved that Thompson's group is also -generated. Since the abelianization of Thompson's group is , it cannot be -generated. However, we recently proved that Thompson's group is "almost" -generated in the sense that every element of whose image in the abelianization forms part of a generating pair of is part of a generating pair of . A natural generalization of -generation is the notion of spread. Recall that the spread of a group is the supremum over all integers such that every non-trivial elements of have a common co-generator in . The uniform spread of a group is the supremum over all integers for which there exists a conjugacy class such that every non-trivial elements of have a common co-generator which belongs to . In this paper we study modified versions of these notions for Thompson's group .
Keywords
Cite
@article{arxiv.2402.19444,
title = {The "spread" of Thompson's group $F$},
author = {Gili Golan},
journal= {arXiv preprint arXiv:2402.19444},
year = {2024}
}
Comments
21 pages, 1 figure. arXiv admin note: text overlap with arXiv:2210.03564