## New answers tagged descriptive-set-theory

3
votes

### Quantifier complexity of the definition of continuity of functions

The following should really be a comment rather than an answer, but it's too long:
Continuity is rarely $\exists^*$ or $\forall^*$ characterizable.
Specifically, consider the following two properties ...

0
votes

### A $\Pi^0_1$ class of $\alpha$-subgenerics for all $\alpha < w_1^{CK}$

So I emailed back and forth with Leo about this and, after the usual part where I drag the conversation into confusion by getting overly specific, I believe I understand how this is supposed to work.
...

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