PP is as Hard as the Polynomial-Time Hierarchy
نویسنده
چکیده
In this paper, two interesting complexity classes, PP and P, are compared with PH, the polynomial-time hierarchy. It is shown that every set in PH is polynomial-time Turing reducible to a set in PP, and PH is included in BP. 0)P. As a consequence of the results, it follows that PP PH (or 03P___ PH) implies a collapse of PH. A stronger result is also shown: every set in PP(PH) is polynomial-time Turing reducible to a set in PP.
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عنوان ژورنال:
- SIAM J. Comput.
دوره 20 شماره
صفحات -
تاریخ انتشار 1991