Analytic equivalence relations satisfying hyperarithmetic-is-recursive
Logic
2013-06-12 v2
Abstract
We prove, in ZF+-determinacy, that for any analytic equivalence relation , the following three statements are equivalent: (1) does not have perfectly many classes, (2) satisfies hyperarithmetic-is-recursive on a cone, and (3) relative to some oracle, for every equivalence class we have that a real computes a member of the equivalence class if and only if . We also show that the implication from (1) to (2) is equivalent to the existence of sharps over .
Keywords
Cite
@article{arxiv.1306.1513,
title = {Analytic equivalence relations satisfying hyperarithmetic-is-recursive},
author = {Antonio Montalbán},
journal= {arXiv preprint arXiv:1306.1513},
year = {2013}
}