A closed subset of Baire space not Medvedev equivalent to any closed set of Cantor space

Joshua Cole

For mass problems $P,Q\subseteq {\mathbb{N}}^{\mathbb{N}}$ (Baire space), $P$ is Medvedev reducible to $Q$ ($P{\le }_{s}Q$) if for some Turing funcional $\hat{I}¦$, $\hat{I}¦(Q)\subseteq P$, and Med…