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Title: Hyperfiniteness for group actions on trees
We identify natural conditions for a countable group acting on a countable tree which imply that the orbit equivalence relation of the induced action on the Gromov boundary is Borel hyperfinite. Examples of this condition include acylindrical actions. We also identify a natural weakening of the aforementioned conditions that implies measure hyperfiniteness of the boundary action. We then document examples of group actions on trees whose boundary action is not hyperfinite.  more » « less
Award ID(s):
2350049
PAR ID:
10595184
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AMS
Date Published:
Journal Name:
Proceedings of the American Mathematical Society
ISSN:
0002-9939
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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