Manifolds with conullity at most two as graph manifolds
arXiv:1611.06572
Abstract
We find necessary and sufficient conditions for a complete -dimensional Riemannian manifold of finite volume, whose curvature tensor has nullity at least , to be a geometric graph manifold. In the process, we show that Nomizu's conjecture, well known to be false in general, is true for manifolds with finite volume.
22 pages, 8 figures. Two references added plus minor corrections