The Schur multiplier, profinite completions and decidability
نویسندگان
چکیده
منابع مشابه
The Schur Multiplier, Profinite Completions and Decidability
We fix a finitely presented group Q and consider short exact sequences 1 → N → Γ → Q → 1 with Γ finitely generated. The inclusion N ↪→ Γ induces a morphism of profinite completions N̂ → Γ̂. We prove that this is an isomorphism for all N and Γ if and only if Q is super-perfect and has no proper subgroups of finite index. We prove that there is no algorithm that, given a finitely presented, residua...
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ژورنال
عنوان ژورنال: Bulletin of the London Mathematical Society
سال: 2010
ISSN: 0024-6093
DOI: 10.1112/blms/bdp133