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An uncountable family of nonorbit equivalent actions of $\mathbb{F} _n$

Author(s): Damien Gaboriau; Sorin Popa
Journal: J. Amer. Math. Soc. 18 (2005), 547-559.
MSC (2000): Primary 37A20, 46L10
Posted: March 28, 2005
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Abstract: For each $ 2 \leq n \leq \infty$, we construct an uncountable family of free ergodic measure preserving actions $\alpha_t$ of the free group $\mathbb{F} _n$ on the standard probability space $(X, \mu)$ such that any two are nonorbit equivalent (in fact, not even stably orbit equivalent). These actions are all ``rigid'' (in the sense of Popa), with the II$_1$factors $L^\infty(X, \mu)\rtimes_{\alpha_t} \mathbb{F} _n$ mutually nonisomorphic (even nonstably isomorphic) and in the class $\mathcal{H}\mathcal{T}_{_{s}}.$


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Additional Information:

Damien Gaboriau
Affiliation: Umpa, UMR CNRS 5669, ENS-Lyon, F-69364 Lyon Cedex 7, France
Email: gaboriau@umpa.ens-lyon.fr

Sorin Popa
Affiliation: Department of Mathematics, Univeristy of California, Los Angeles, California 90095-1555
Email: popa@math.ucla.edu

DOI: 10.1090/S0894-0347-05-00480-7
PII: S 0894-0347(05)00480-7
Received by editor(s): September 12, 2003
Posted: March 28, 2005
Additional Notes: The first author wishes to thank the C.N.R.S
The second author was supported in part by NSF Grant 0100883
Copyright of article: Copyright 2005, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.


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