A Note on the continuous extensions of injective morphisms between free groups to relatively free profinite groups

Let V be a pseudovariety of finite groups such that free groups are residually V, and let ϕ: F(A) → F(B) be an injective morphism between finitely generated free groups. We characterize the situations where the continuous extension ˆϕ of ϕ between the pro-V completions of F(A) and F(B) is also injec...

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Detalles Bibliográficos
Autores: Coulbois, Thierry, Sapir, Mark V., Weil, Pascal
Tipo de recurso: artículo
Fecha de publicación:2003
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:2019
Acceso en línea:https://ddd.uab.cat/record/2019
https://dx.doi.org/urn:doi:10.5565/PUBLMAT_47203_10
Access Level:acceso abierto
Palabra clave:Profinite topology
Rank of subgroups of free groups
Monomorphisms between free groups
Descripción
Sumario:Let V be a pseudovariety of finite groups such that free groups are residually V, and let ϕ: F(A) → F(B) be an injective morphism between finitely generated free groups. We characterize the situations where the continuous extension ˆϕ of ϕ between the pro-V completions of F(A) and F(B) is also injective. In particular, if V is extension-closed, this is the case if and only if ϕ(F(A)) and its pro-V closure in F(B) have the same rank. We examine a number of situations where the injectivity of ˆϕ can be asserted, or at least decided, and we draw a few corollaries.