Direct factors of profinite completions and decidability
نویسندگان
چکیده
منابع مشابه
Direct Factors of Profinite Completions and Decidability
We consider finitely presented, residually finite groups G and finitely generated normal subgroups A such that the inclusion A ↪→ G induces an isomorphism from the profinite completion of A to a direct factor of the profinite completion of G. We explain why A need not be a direct factor of a subgroup of finite index in G; indeed G need not have a subgroup of finite index that splits as a non-tr...
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ژورنال
عنوان ژورنال: Journal of Group Theory
سال: 2009
ISSN: 1433-5883,1435-4446
DOI: 10.1515/jgt.2008.067