Parabolic isometries of CAT(0) spaces and CAT(0) dimensions
Abstract
We study discrete groups from the view point of a dimension gap in connection to CAT(0) geometry. Developing studies by Brady-Crisp and Bridson, we show that there exist finitely presented groups of geometric dimension 2 which do not act properly on any proper CAT(0) spaces of dimension 2 by isometries, although such actions exist on CAT(0) spaces of dimension 3. Another example is the fundamental group, G, of a complete, non-compact, complex hyperbolic manifold M with finite volume, of complex-dimension n > 1. The group G is acting on the universal cover of M, which is isometric to H^n_C. It is a CAT(-1) space of dimension 2n. The geometric dimension of G is 2n-1. We show that G does not act on any proper CAT(0) space of dimension 2n-1 properly by isometries. We also discuss the fundamental groups of a torus bundle over a circle, and solvable Baumslag-Solitar groups.
Keywords
Cite
@article{arxiv.math/0308274,
title = {Parabolic isometries of CAT(0) spaces and CAT(0) dimensions},
author = {Koji Fujiwara and Takashi Shioya and Saeko Yamagata},
journal= {arXiv preprint arXiv:math/0308274},
year = {2014}
}
Comments
Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol4/agt-4-38.abs.html