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arXiv · 1307.1935

Strong embeddability and extensions of groups

Ronghui Ji·Crichton Ogle·Bobby Ramsey
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Abstract

We introduce the notion of strong embeddability for a metric space. This property lies between coarse embeddability and property A. A relative version of strong embeddability is developed in terms of a family of set maps on the metric space. When restricted to discrete groups, this yields relative coarse embeddability. We verify that groups acting on a metric space which is strongly embeddable has this relative strong embeddability, provided the stabilizer subgroups do. As a corollary, strong embeddability is preserved under group extensions.

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Ronghui Ji, Crichton Ogle, Bobby Ramsey. 2013-11-08. Strong embeddability and extensions of groups. https://arxiv.org/abs/1307.1935

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