Year: 2026
Type: preprint
Abstract: We demonstrate that the conjugacy growth series for the Heisenberg groups $H_n(\mathbb{Z})$ is never algebraic, irrespective of the generating set. This makes progress towards the conjecture that all finitely presented groups that are not virtually abelian have irrational conjugacy growth series. Contrary to the group $H_3(\mathbb{Z})$, where the conjugacy growth is $n^2\log(n)$, the conjugacy growth of the other Heisenberg groups is polynomial, making these groups the first known nilpotent groups where the irrationality does not follow from the asymptotic growth.
Source: arXiv (Cornell University)
Author: Vandeputte, Lukas
Institution: KU Leuven
Language: English
Subfield: Geometry and Topology
Field: Mathematics
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7224082225