%0 Journal Article
%T 3-manifolds with(out) metrics of nonpositive curvature
%A Bernhard Leeb
%J Mathematics
%D 1994
%I arXiv
%R 10.1007/BF01231445
%X In the context of Thurstons geometrisation program we address the question which compact aspherical 3-manifolds admit Riemannian metrics of nonpositive curvature. We show that non-geometric Haken manifolds generically, but not always, admit such metrics. More precisely, we prove that a Haken manifold with, possibly empty, boundary of zero Euler characteristic admits metrics of nonpositive curvature if the boundary is non-empty or if at least one atoroidal component occurs in its canonical topological decomposition. Our arguments are based on Thurstons Hyperbolisation Theorem. We give examples of closed graph-manifolds with linear gluing graph and arbitrarily many Seifert components which do not admit metrics of nonpositive curvature.
%U http://arxiv.org/abs/dg-ga/9410002v1