Martin-ll of Random and Pa-complete Sets
نویسنده
چکیده
A set A is Martin-LL of random ii the class fAg does not have 0 1-measure 0. A set A is PA-complete if one can compute relative to A a consistent and complete extension of Peano Arithmetic. It is shown that every Martin-LL of random set either permits to solve the halting problem K or is not PA-complete. This result implies a negative answer to the question of Ambos-Spies and Ku cera whether there is a Martin-LL of random set not above K which is also PA-complete.
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