In Search of an Easy Witness: Exponential Time vs. Probabilistic Polynomial Time
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چکیده
Restricting the search space f gn to the set of truth tables of easy Boolean functions on logn variables as well as using some known hardness randomness tradeo s we establish a number of results relating the complexity of exponential time and probabilistic polynomial time complexity classes In particular we show that NEXP P poly NEXP MA this can be interpreted as saying that no derandomization of MA and hence of promise BPP is possible unless NEXP contains a hard Boolean function We also prove several downward closure results for ZPP RP BPP and MA e g we show EXP BPP EE BPE where EE is the double exponential time class and BPE is the exponential time analogue of BPP
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تاریخ انتشار 2001