Non-reducibility of Isomorphism of Counterexamples to Vaught’s Conjecture to the Admissibility Equivalence Relation
نویسنده
چکیده
Let T be a counterexample to Vaught’s conjecture. Let ET denote the isomorphism equivalence relation of T . Let Fω1 be the countable admissible ordinal equivalence relation defined on ω2 by x Fω1 y if and only if ωx 1 = ω y 1 . This note will show that in L and set-generic extensions of L, ¬(ET ≤∆11 Fω1 ). Using ZFC, if T is a non-minimal counterexample to Vaught’s conjecture, then ¬(ET ≤∆11 Fω1 ).
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