K-Triviality of Closed Sets and Continuous Functions
نویسندگان
چکیده
We investigate the notion of K-triviality for closed sets and continuous functions in 2N. For every K-trivial degreee d, there exists a closed set of degree d and a continuous function of degree d. Every K-trivial closed set contains a K-trivial real. There exists a K-trivial Π1 class with no computable elements. A closed set is K-trivial if and only if it is the set of zeroes of some K-trivial continuous function. We give a density result for the Medvedev degrees of K-trivial Π1 sets. If W ≤T A′, then W can compute a path through every A′-decidable random closed set if and only if W ≡T A′.
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ورودعنوان ژورنال:
- J. Log. Comput.
دوره 19 شماره
صفحات -
تاریخ انتشار 2009