Cofinal families of Borel equivalence relations and quasiorders
نویسنده
چکیده
Families of Borel equivalence relations and quasiorders that are cofinal with respect to the Borel reducibility ordering, ≤B , are constructed. There is an analytic ideal on ù generating a complete analytic equivalence relation and any Borel equivalence relation reduces to one generated by a Borel ideal. Several Borel equivalence relations, among them Lipschitz isomorphism of compact metric spaces, are shown to be Kó complete. §
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 70 شماره
صفحات -
تاریخ انتشار 2005