PD4-complexes with π2 a projective Z[π1]-module
Jonathan A. Hillman
所有作者
Jonathan A. Hillman
文献摘要
Let X be a PD4-complex and let π=π1(X). If π is torsion-free and π2(X) is a finitely generated projective Z[π]-module then either π is free or π is FP and c.d.π=4. If, moreover, H3(π;Z[π])=0 then π is a free product of PD4-groups and a free group.