Reverse Mathematics and Uniformity in Proofs without Excluded Middle
نویسندگان
چکیده
We prove that if a Π2 sentence is provable in a certain theory of higher order arithmetic without the law of the excluded middle then it is uniformly provable in the weak classical theory RCA0. Applying the contrapositive of this result, we give three examples where results of reverse mathematics can be used to show nonexistence of proofs in certain intuitionistic systems.
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عنوان ژورنال:
- Notre Dame Journal of Formal Logic
دوره 52 شماره
صفحات -
تاریخ انتشار 2011