Connectedness at infinity of complete K\"ahler manifolds and locally symmetric spaces

Abstract

One of the main purposes of this paper is to prove that on a complete K\"ahler manifold of dimension $m$, if the holomorphic bisectional curvature is bounded from below by -1 and the minimum spectrum $\lambda_1(M) \ge m^2$, then it must either be connected at infinity or diffeomorphic to $\Bbb R \times N$, where $N$ is a compact quotient of the Heisenberg group. Similar type results are also proven for irreducible, locally symmetric spaces of noncompact type. Generalizations to complete K\"ahler manifolds satisfying a weighted Poincar\'e inequality are also being considered