Title says it:
Is every $\Pi_2$ set the continuous (surjective) image of a $\Delta_2$ set? Any book suggestions for questions like these?
2026-03-29 10:16:43.1774779403
Is every $\Pi_2$ set the continuous image of a $\Delta_2$ set?
78 Views Asked by user17762 https://math.techqa.club/user/user17762/detail AtRelated Questions in DESCRIPTIVE-SET-THEORY
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