Borel ideals vs. Borel sets of countable relations and trees
نویسندگان
چکیده
منابع مشابه
Countable Borel Equivalence Relations
This paper is a contribution to a new direction in descriptive set theory that is being extensively pursued over the last decade or so. It deals with the development of the theory of definable actions of Polish groups, the structure and classification of their orbit spaces, and the closely related study of definable equivalence relations. This study is motivated by basic foundational questions,...
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ing from the proof given above for Gaboriau-Popa we obtain theorems such as: Theorem 2.10 Let (X, d) be a complete, separable metric space equipped with an atomless Borel probability measure μ. Suppose Γ acts ergodically by measure preserving transformations on (X,μ) and the action on (X, d) is expansive. Let (Et)0<t<1 be a collection of distinct countable Borel equivalence relations on X with:...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 1989
ISSN: 0168-0072
DOI: 10.1016/0168-0072(80)90003-2