Universal Borel mappings and Borel actions of groups
نویسندگان
چکیده
منابع مشابه
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If the countable group G has a nonabelian free subgroup, then there exists a standard Borel G-space such that the corresponding orbit equivalence relation is countable universal. In this paper, we will consider the question of whether the converse also holds.
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 2008
ISSN: 0166-8641
DOI: 10.1016/j.topol.2007.05.029