On Turing Reducibility
نویسندگان
چکیده
We show that the transitivity of pointwise Turing reducibility on the recursively enumerable sets of integers cannot be proven in P− + IΣ1, first order arithmetic with induction limited to Σ1 predicates. We produce a example of intransitivity in a nonstandard model of P+IΣ1 by a finite injury priority construction.
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