Normal subgroups of profinite groups of finite cohomological dimension
نویسندگان
چکیده
We study a profinite group G of finite cohomological dimension with (topologically) finitely generated closed normal subgroup N . If G is pro-p and N is either free as a pro-p group or a Poincaré group of dimension 2 or analytic pro-p, we show that G/N has virtually finite cohomological dimension cd(G) − cd(N). Some other cases when G/N has virtually finite cohomological dimension are considered too. If G is profinite, the case of N projective or the profinite completion of the fundamental group of a compact surface is considered.
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