Bi-Immunity Results for Cheatable Sets
نویسنده
چکیده
An oracle A is k-cheatable if there is a polynomial-time algorithm to determine the answers to 2 k parallel queries to A from the answers to only k queries to some other oracle B. It is known that 1-cheatable sets cannot be bi-immune for P. In contrast, we construct 2-cheatable sets that are bi-immune for arbitrary time complexity classes. In addition , for each k, we construct a set that is (k + 1)-cheatable, but not k-cheatable; we show that this separation does not hold with bi-immunity. We show that if a recursive set A is bi-immune for P then there exists an innnite 1-cheatable set that is polynomial-time m-reducible to A. Consequently if NP contains a set that is bi-immune for P then NP contains a set that is not polynomial-time Turing-equivalent to a self-reducible set.
منابع مشابه
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 73 شماره
صفحات -
تاریخ انتشار 1990