A non-splitting theorem in the enumeration degrees
نویسنده
چکیده
We complete a study of the splitting/non-splitting properties of the enumeration degrees below 0′e by proving an analog of Harrington’s non-splitting theorem for the Σ2 enumeration degrees. We show how non-splitting techniques known from the study of the c.e. Turing degrees can be adapted to the enumeration degrees.
منابع مشابه
Exact Pair Theorem for the ω-Enumeration Degrees
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ورودعنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 160 شماره
صفحات -
تاریخ انتشار 2009