A note on virtual duality and automorphism groups of right-angled Artin groups

A theorem of Brady and Meier states that a right-angled Artin group is a duality group if and only if the flag complex of the defining graph is Cohen--Macaulay. We use this to give an example of a RAAG with the property that its outer automorphism group is not a virtual duality group. This gives a p...

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Main Authors: Wade, RD, Brück, B
Format: Journal article
Language:English
Published: Cambridge University Press 2023
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author Wade, RD
Brück, B
author_facet Wade, RD
Brück, B
author_sort Wade, RD
collection OXFORD
description A theorem of Brady and Meier states that a right-angled Artin group is a duality group if and only if the flag complex of the defining graph is Cohen--Macaulay. We use this to give an example of a RAAG with the property that its outer automorphism group is not a virtual duality group. This gives a partial answer to a question of Vogtmann. In an appendix, Brück describes how he used a computer-assisted search to find further examples.
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spelling oxford-uuid:1e991a3f-ff43-48af-b7a1-50e569798ca72024-01-17T13:31:02ZA note on virtual duality and automorphism groups of right-angled Artin groupsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:1e991a3f-ff43-48af-b7a1-50e569798ca7EnglishSymplectic ElementsCambridge University Press2023Wade, RDBrück, BA theorem of Brady and Meier states that a right-angled Artin group is a duality group if and only if the flag complex of the defining graph is Cohen--Macaulay. We use this to give an example of a RAAG with the property that its outer automorphism group is not a virtual duality group. This gives a partial answer to a question of Vogtmann. In an appendix, Brück describes how he used a computer-assisted search to find further examples.
spellingShingle Wade, RD
Brück, B
A note on virtual duality and automorphism groups of right-angled Artin groups
title A note on virtual duality and automorphism groups of right-angled Artin groups
title_full A note on virtual duality and automorphism groups of right-angled Artin groups
title_fullStr A note on virtual duality and automorphism groups of right-angled Artin groups
title_full_unstemmed A note on virtual duality and automorphism groups of right-angled Artin groups
title_short A note on virtual duality and automorphism groups of right-angled Artin groups
title_sort note on virtual duality and automorphism groups of right angled artin groups
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