The Importance of Π1 Classes in Effective Randomness
نویسندگان
چکیده
We prove a number of results in effective randomness, using methods in which Π1 classes play an essential role. Amongst many others, the results proved include the fact that every PA Turing degree is the join of two random Turing degrees, and the existence of a minimal pair of LR degrees below the LR degree of the halting problem.
منابع مشابه
The importance of Pi01 classes in effective randomness
We prove a number of results in effective randomness, using methods in which Π1 classes play an essential role. The results proved include the fact that every PA Turing degree is the join of two random Turing degrees, and the existence of a minimal pair of LR degrees below the LR degree of the halting problem.
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تاریخ انتشار 2008