Free product actions with relative property (T) and trivial outer automorphism groups
نویسندگان
چکیده
منابع مشابه
Free Product Actions with Relative Property (T) and Trivial Outer Automorphism Groups
We show that every non-amenable free product of groups admits free ergodic probability measure preserving actions which have relative property (T) in the sense of S. Popa [Pop06, Def. 4.1]. There are continuum many such actions up to orbit equivalence and von Neumann equivalence, and they may be chosen to be conjugate to any prescribed action when restricted to the free factors. We exhibit also...
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For each countable group Q we produce a short exact sequence 1 → N → G → Q → 1 where G is f.g. and has a graphical 1 6 presentation and N is f.g. and satisfies property T . As a consequence we produce a group N with property T such that Out(N) is infinite. Using the tools developed we are also able to produce examples of nonHopfian and non-coHopfian groups with property T . One of our main tool...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2011
ISSN: 0022-1236
DOI: 10.1016/j.jfa.2010.09.013