Free-by-Demushkin pro-p groups
نویسندگان
چکیده
We give an example of a short exact sequence 1 → N → G → D → 1 of pro-p groups such that the cohomological dimension cd(G) = 2, G is (topologically) finitely generated, N is a free pro-p group of infinite rank, D is a Demushkin group, for every closed subgroup S of G containing N and any natural number n the inflation map H2(S/N,Z/(pn)) → H2(S,Z/(pn)) is an isomorphism but G is not a free pro-p product of a free pro-p group by a Demushkin group. This is a group theoretic version of a question raised by T. Würfel for some special Galois groups.
منابع مشابه
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تاریخ انتشار 2008