Nisan-Wigderson generators in proof systems with forms of interpolation

نویسنده

  • Ján Pich
چکیده

Proof complexity generators are used to define candidate hard tautologies for strong proof systems like Frege proof system or Extended Frege. They were independently introduced by Krajı́ček [3] and by Alekhnovich, Ben-Sasson, Razborov, and Wigderson [1]. Roughly speaking, the tautologies encode the fact that b / ∈ Rng(g) for an element b outside of the range of a generator g : {0, 1} 7−→ {0, 1}, where m > n, defined by a circuit of size m. If g : {0, 1}t(n)O(1) 7−→ {0, 1}2n sends codes of t(n)-size circuits with n inputs to the truth tables of functions they compute, then the tautologies f / ∈ Rng(g) say that f has no t(n)-size circuits. Denote such a formula by ¬Circuitt(n)(f). The hardness of such tautologies can be interpreted as the hardness of proving circuit lower bounds. This captures an element of self-reference in the P vs NP problem. As Razborov pointed out in [7], to prove the hardness of ¬Circuitt(n)(f) in a proof system, it is sufficient to show that there exists a generator g : {0, 1}0 7−→ {0, 1}2n with arbitrary t0(n) ≤ 2 and such that g is

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عنوان ژورنال:
  • Math. Log. Q.

دوره 57  شماره 

صفحات  -

تاریخ انتشار 2010