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Answer by Dan Turetsky for Analytic sets and Turing determinacy
I believe this fails under $V=L$. If $P$ is a pointed perfect set and $X$ is a real, let $P(X)$ be the element of $P$ where at every split we choose according to the next bit of $X$. So $X\oplus P...
View ArticleAnalytic sets and Turing determinacy
I wonder whether the following question have a positive answer within $ZFC$.Question If $\{A_n\}_{n\in \omega}$ is a sequence of analytic sets so that $\bigcup_n A_n=2^{\omega}$, then there must be...
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