Cupping D20 Enumeration Degrees to 0 e '
نویسندگان
چکیده
In this paper we prove that every nonzero ∆2 e-degree is cuppable to 0e by a 1-generic ∆ 0 2 e-degree (so low and nontotal) and that every nonzero ω-c.e. e-degree is cuppable to 0e by an incomplete
منابع مشابه
The limitations of cupping in the local structure of the enumeration degrees
We prove that a sequence of sets containing representatives of cupping partners for every nonzero ∆2 enumeration degree cannot have a ∆ 0 2 enumeration. We also prove that no subclass of the Σ 2 enumeration degrees containing the nonzero 3-c.e. enumeration degrees can be cupped to 0e by a single incomplete Σ 2 enumeration degree.
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