Finite presentability of F(3/2)

Determine whether the Thompson-style group F(3/2) = G([0,1]; Z[1/6], <3/2>) is finitely presented; specifically, ascertain whether there exists a finite set of defining relations that, together with a finite generating set, presents this group.

Background

The group F(3/2) is a Bieri–Strebel type generalization of Thompson’s group, consisting of orientation-preserving piecewise-linear homeomorphisms of [0,1] with slopes restricted to powers of 3/2 and breakpoints in Z[1/6]. In this paper the authors prove that F(3/2) is finitely generated by two specific elements, addressing a longstanding question that arose since Stein’s paper of related groups.

Beyond finite generation, a central structural question is finite presentability, which requires a finite set of relations among generators. While the authors exhibit certain relations (see their formulas in the cited figure/section \Cref{xiv2}), they note that determining whether a finite set suffices remains unresolved and anticipate that any such relations could be long and complicated.

References

The question of whether it is finitely presented remains open, although in view of the formulas in \Cref{xiv2}, we suspect that possible relations will be long and complicated.

Finite generation for the group $F\left(\frac32\right)$ (2409.09195 - Burillo et al., 13 Sep 2024) in Introduction