The Continuity of Cupping to 0 0
نویسندگان
چکیده
It is shown that, if a, b are recursively enumerable degrees such that 0 < a < 0 0 and a b = 0 0 , then there exists a recursively enumerable degree c such that c < a and c b = 0 0 .
منابع مشابه
Universal Cupping Degrees
Cupping nonzero computably enumerable (c.e. for short) degrees to 0′ in various structures has been one of the most important topics in the development of classical computability theory. An incomplete c.e. degree a is cuppable if there is an incomplete c.e. degree b such that a∪b = 0′, and noncuppable if there is no such degree b. Sacks splitting theorem shows the existence of cuppable degrees....
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تاریخ انتشار 1993