Undecidability Results for Low Complexity Time Classes
نویسندگان
چکیده
We prove that the theory of EXPTIME degrees with respect to polynomial time Turing and many-one reducibility is undecidable. To do so we use a coding method based on ideal lattices of Boolean algebras which was introduced in Nies 12]. The method can be applied in fact to all time classes given by a time constructible function which dominates all polynomials. By a similar method, we construct an oracle U such that Th(NP U ;) is undecidable.
منابع مشابه
Undecidability Results for Low Complexity Degree Structures
We prove that the theory of EXPTIME degrees with respect to polynomial time Turing and many-one reducibility is undecidable. To do so we use a coding method based on ideal lattices of Boolean algebras which was introduced in [7]. The method can be applied in fact to all hyper-polynomial time classes.
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We prove that the theory of EXPTIME degrees with respect to polynomial time Turing and many-one re-ducibility is undecidable. To do so we use a coding method based on ideal lattices of Boolean algebras which was introduced in 7]. The method can be applied in fact to all hyper-polynomial time classes.
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ورودعنوان ژورنال:
- J. Comput. Syst. Sci.
دوره 60 شماره
صفحات -
تاریخ انتشار 2000