Detecting ends of residually finite groups in profinite completions
نویسندگان
چکیده
منابع مشابه
Profinite groups, profinite completions and a conjecture of Moore
Let R be any ring (with 1), Γ a group and RΓ the corresponding group ring. Let H be a subgroup of Γ of finite index. Let M be an RΓ−module, whose restriction to RH is projective. Moore’s conjecture [5]: Assume for every nontrivial element x in Γ, at least one of the following two conditions holds: M1) 〈x〉 ∩ H 6= {e} (in particular this holds if Γ is torsion free) M2) ord(x) is finite and invert...
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ژورنال
عنوان ژورنال: Mathematical Proceedings of the Cambridge Philosophical Society
سال: 2013
ISSN: 0305-0041,1469-8064
DOI: 10.1017/s0305004113000418