Unipotent linear suspensions of free groups

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Dahmani, François, Touikan, Nicholas
Format: Preprint
Veröffentlicht: 2023
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866909231292088320
author Dahmani, François
Touikan, Nicholas
author_facet Dahmani, François
Touikan, Nicholas
contents Motivated by the study of the conjugacy problem for outer automorphism of free groups, we develop the algorithmic theory of the free-by-cyclic group produced by unipotent linearly growing automorphisms of f.g. free groups. We compute canonical splittings of these suspensions as well as their subgroups. We compute their automorphism groups. We show that this class of suspensions is effectively coherent. We solve the mixed Whitehead problem in these suspensions and show that their subgroups all satisfy the Minkowski property, i.e. that torsion in their outer automorphism group is faithfully represented in some computable finite quotients. An application of our results is a solution to the conjugacy problem for outer automorphisms of free groups whose polynomially growing part is unipotent linear.
format Preprint
id arxiv_https___arxiv_org_abs_2305_11274
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Unipotent linear suspensions of free groups
Dahmani, François
Touikan, Nicholas
Group Theory
20F28, 20E36, 20E05, 20E06
Motivated by the study of the conjugacy problem for outer automorphism of free groups, we develop the algorithmic theory of the free-by-cyclic group produced by unipotent linearly growing automorphisms of f.g. free groups. We compute canonical splittings of these suspensions as well as their subgroups. We compute their automorphism groups. We show that this class of suspensions is effectively coherent. We solve the mixed Whitehead problem in these suspensions and show that their subgroups all satisfy the Minkowski property, i.e. that torsion in their outer automorphism group is faithfully represented in some computable finite quotients. An application of our results is a solution to the conjugacy problem for outer automorphisms of free groups whose polynomially growing part is unipotent linear.
title Unipotent linear suspensions of free groups
topic Group Theory
20F28, 20E36, 20E05, 20E06
url https://arxiv.org/abs/2305.11274