A theorem about Σ¹₁ equivalence relations

A theorem about $\Sigma ^1_1$ equivalence relations
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Proc. Amer. Math. Soc. 150 (2022), 2729-2731 Request permission

Any $\Sigma ^1_1$ equivalence relation which is invariant under hyperarithmetic equivalence is also invariant under admissible ordinal equivalence.

References

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