Bar recursion is not T+min definable
نویسنده
چکیده
This note supplies the proof of a theorem stated in the forthcoming book by Longley and Normann: namely, that Spector’s bar recursion functional is not representable by a left-well-founded sequential procedure, and hence is not definable in the language T + min (that is, Gödel’s System T augmented with the minimization operator), for instance within the Kleene–Kreisel model of total continuous functionals.
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تاریخ انتشار 2015