Some Berwald spaces of non-positive flag curvature

Abstract

In this paper, by using left invariant Riemannian metrics on some three-dimensional Lie groups, we construct some complete non-Riemannian Berwald spaces of non-positive flag curvature and several families of geodesically complete locally Minkowskian spaces of zero constant flag curvature. © 2009 Elsevier B.V. All rights reserved.