Detecting large groups

Let G be a finitely presented group, and let p be a prime. Then G is 'large' (respectively, 'p-large') if some normal subgroup with finite index (respectively, index a power of p) admits a non-abelian free quotient. This paper provides a variety of new methods for detecting wheth...

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Main Author: Lackenby, M
Format: Journal article
Language:English
Published: 2007
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author Lackenby, M
author_facet Lackenby, M
author_sort Lackenby, M
collection OXFORD
description Let G be a finitely presented group, and let p be a prime. Then G is 'large' (respectively, 'p-large') if some normal subgroup with finite index (respectively, index a power of p) admits a non-abelian free quotient. This paper provides a variety of new methods for detecting whether G is large or p-large. These relate to the group's profinite and pro-p completions, to its first L2-Betti number and to the existence of certain finite index subgroups with 'rapid descent'. The paper draws on new topological and geometric techniques, together with a result on error-correcting codes.
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spelling oxford-uuid:3a083e31-1011-40ed-a53d-e9f1af8590f12022-03-26T13:59:07ZDetecting large groupsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:3a083e31-1011-40ed-a53d-e9f1af8590f1EnglishSymplectic Elements at Oxford2007Lackenby, MLet G be a finitely presented group, and let p be a prime. Then G is 'large' (respectively, 'p-large') if some normal subgroup with finite index (respectively, index a power of p) admits a non-abelian free quotient. This paper provides a variety of new methods for detecting whether G is large or p-large. These relate to the group's profinite and pro-p completions, to its first L2-Betti number and to the existence of certain finite index subgroups with 'rapid descent'. The paper draws on new topological and geometric techniques, together with a result on error-correcting codes.
spellingShingle Lackenby, M
Detecting large groups
title Detecting large groups
title_full Detecting large groups
title_fullStr Detecting large groups
title_full_unstemmed Detecting large groups
title_short Detecting large groups
title_sort detecting large groups
work_keys_str_mv AT lackenbym detectinglargegroups