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Set Theory Seminar: Moshe Teutch (HUJI) | Einstein Institute of Mathematics

Set Theory Seminar: Moshe Teutch (HUJI)

Date: 
Wed, 13/10/202114:00-16:00
Title:
Structurability of Countable Borel Equivalence Relations
Abstract:
Chen and Kechris defined when a countable Borel equivalence relation (CBER) E on a standard Polish space X is structurable by a countable relational model M: The relations must define Borel subsets of a power of X, and the restriction to each E-class must give a model isomorphic to M. The structurability of E by various models can shed light on its properties as a CBER. One interesting question is, Which models structure every CBER? I'll discuss an adaptation by Marks of a construction of Ackerman, Freer, and Patel which finds a large class of such models. I'll also show some applications of their construction to this question. Time permitting I'll discuss some related results and techniques from my thesis.