Logic Seminar

This talk will present some results from the paper "Structurable equivalence relations" by Kechris.  We will define the notion of an equivalence relation which is structurable with respect to some class of first-order structures.  By a result of Miller, every Borel class of first-order structures has a universal structurable equivalence relation.  We will sketch the result that characterizes non-smoothness of this universal relation for the class of structures isomorphic to a single fixed structure, and if time permits, describe the generalization to more general classes of structures.