Embedding $FD(\omega )$ into ${\mathcal{P}}_s$ densely

Joshua A. Cole

Let ${\mathcal{P}}_s$ be the lattice of degrees of non-empty ${\Pi }_1^0$ subsets of $2^{\omega }$ under Medvedev reducibility. Binns and Simpson proved that $FD(\omega )$, the free distributive lattic…