Coarse amenability and discreteness
arXiv:1307.3943 · doi:10.1017/S1446788715000312
Abstract
This paper is devoted to dualization of paracompactness to the coarse category via the concept of -disjointness. Property A of G.Yu can be seen as a coarse variant of amenability via partitions of unity and leads to a dualization of paracompactness via partitions of unity. On the other hand, finite decomposition complexity of G.Yu and straight finite decomposition complexity of Dranishnikov-Zarichnyi employ -disjointness as the main concept. We generalize both concepts to that of countable asymptotic dimension and our main result shows that it is a subclass of of spaces with Property A. In addition, it gives a necessary and sufficient condition for spaces of countable asymptotic dimension to be of finite asymptotic dimension.
12 pages, to appear in Journal of the Australian Math Society