Filling invariants at infinity and the Euclidean rank of Hadamard spaces
Abstract
Description
In this paper we study a homological version of the higher-dimensional divergence invariants defined by Brady and Farb. We show that they are quasi-isometry invariants in the class of proper cocompact Hadamard spaces in the sense of Alexandrov and that they can moreover be used to detect the Euclidean rank of such spaces. We thereby extend results of Brady-Farb, Leuzinger, and Hindawi from the setting of symmetric spaces of non-compact type to that of singular Hadamard spaces. Finally, we exhibit the optimal power for the growth of the divergence above the rank for symmetric spaces of non-compact type and for Hadamard spaces with strictly negative upper curvature bound.
In this new version we add a theorem which shows that the homological divergence functions are quasi-isometry invariants in the class of proper cocompact Hadamard spaces. This extends the corresponding theorem of Brady and Farb
In this new version we add a theorem which shows that the homological divergence functions are quasi-isometry invariants in the class of proper cocompact Hadamard spaces. This extends the corresponding theorem of Brady and Farb