The cohomological restriction map and FP-infinity groups

Abstract

We ask, following Bartholdi, whether it is true that the kernel of the restriction map from the cohomology of a group G to the cohomology of a finite index subgroup H is finitely generated as an ideal. We show that in case the group has virtual finite cohomological dimension it is true, and we will show that if G does not have virtual finite cohomological dimension it might not be true, even in case G is an FP infinity group.Comment: 17 pagee