2014/12/05 by Ged Corob Cook, Cook, Ged Corob
Mathematics · #FOS: Mathematics #Group Theory (math.GR) #math.GR
paper · pdf · doi:10.48550/arxiv.1412.1876
arxiv created 2014/12/05 · arxiv updated 2014/12/08
Suppose R is a profinite ring. We construct a large class of profinite groups \widehat\scriptstyle\bf L'\scriptstyle\bf HR\mathfrakF, including all soluble profinite groups and profinite groups of finite cohomological dimension over R. We show that, if G ∈ \widehat\scriptstyle\bf L'\scriptstyle\bf HR\mathfrakF is of type FP_∞ over R, then there is some n such that HRn(G,R [[ G ]]) ≠ 0, and deduce that torsion-free soluble pro-p groups of type FP_∞ over ℤp have finite rank, thus answering the torsion-free case of a conjecture of Kropholler.