English

Equivariant Coarse (Co-)Homology Theories

Algebraic Topology 2022-07-27 v4 K-Theory and Homology Metric Geometry

Abstract

We present an Eilenberg-Steenrod-like axiomatic framework for equivariant coarse homology and cohomology theories. We also discuss a general construction of such coarse theories from topological ones and the associated transgression maps. A large part of this paper is devoted to showing how some well-established coarse (co-)homology theories, whose equivariant versions are either already known or will be introduced in this paper, fit into this setup. Furthermore, a new and more flexible notion of coarse homotopy is given which is more in the spirit of topological homotopies. Some, but not all, coarse (co-)homology theories are even invariant under these new homotopies. They also led us to a meaningful concept of topological actions of locally compact groups on coarse spaces.

Keywords

Cite

@article{arxiv.2006.02053,
  title  = {Equivariant Coarse (Co-)Homology Theories},
  author = {Christopher Wulff},
  journal= {arXiv preprint arXiv:2006.02053},
  year   = {2022}
}

Comments

v2: added Lemma 6.10 about a nice metrization of the Rips complex and further minor changes. 55 + $\epsilon$ pages v3: Numerous corrections and improvements. Also, the introduction has been rewritten to clarify the purpose of this paper. v4: published version