Turing Degrees and Muchnik Degrees of Recursively Bounded DNR Functions
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چکیده
منابع مشابه
An extension of the recursively enumerable Turing degrees
We embed the upper semilattice of r.e. Turing degrees into a slightly larger structure which is better behaved and more foundationally relevant. For P,Q ⊆ 2, we say P is Muchnik reducible to Q if for all Y ∈ Q there exists X ∈ P such that X is Turing reducible to Y . We let Pw denote the lattice of Muchnik degrees of nonempty Π1 subsets of 2. Pw is a countable distributive lattice with 0 and 1....
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