Pseudorandom generators hard for propositional proof systems
نویسنده
چکیده
Based on the concept of pseudorandom generators, the notation of a generator which is hard for a proof system is introduced. Such a generator admits a superpolynomial lower bound. For the resolution proof system a hard generator is constructed which bases on expanders.
منابع مشابه
Pseudorandom Generators in Propositional Proof Complexity
We call a pseudorandom generator Gn : {0, 1}n → {0, 1}m hard for a propositional proof system P if P can not efficiently prove the (properly encoded) statement Gn(x1, . . . , xn) 6= b for any string b ∈ {0, 1}m. We consider a variety of “combinatorial” pseudorandom generators inspired by the Nisan-Wigderson generator on the one hand, and by the construction of Tseitin tautologies on the other. ...
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تاریخ انتشار 2009