Strong separations of the polynomial hierarchy with oracles: constructive separations by immune and simple sets
نویسندگان
چکیده
منابع مشابه
Separations by Random Oracles and \ Almost " Classes for Generalized
Let r and s be two binary relations on 2 N which are meant as reducibilities. Let both relations be closed under nite variation (of their set arguments) and consider the uniform distribution on 2 N , which is obtained by choosing elements of 2 N by independent tosses of a fair coin. Then we might ask for the probability that the lower r-cone of a randomly chosen set X, that is, the class of all...
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Let r and s be two binary relations on 2 N which are meant as reducibilities. Let both relations be closed under nite variation (of their set arguments) and consider the uniform distribution on 2 N , which is obtained by choosing elements of 2 N by independent tosses of a fair coin. Then we might ask for the probability that the lower r-cone of a randomly chosen set X, that is, the class of all...
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1 SUMMARY As part of a study of almost-everywhere complex sets, we i n vestigate sets that are immune to AC 0 ; that is, sets with no innnite subset in AC 0. W e show that such sets exist in P PP and in DSPACElog n log n. Our main result is an oracle construction indicating that any improvement in these immunity results will represent a signiicant advance, in that we show that any answer to the...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1992
ISSN: 0304-3975
DOI: 10.1016/0304-3975(92)90232-5