Affiliation:
1. Graduate School of Mathematical Sciences, The University of Tokyo, Komaba, Tokyo 153-8914, Japan
Abstract
For certain HNN extensions including Baumslag–Solitar groups, a treeing is constructed from their certain probability-measure-preserving actions. This is a treeing of a quotient groupoid of the translation groupoid associated with their actions. As its application, for some of those HNN extensions, we show that the kernel of the modular homomorphism is measure equivalent to the direct product of the free group of infinite rank and [Formula: see text].
Funder
Japan Society for the Promotion of Science
Publisher
World Scientific Pub Co Pte Ltd