Superpolynomial lower bounds for circuits with almost maximal number of negations

Stasys Jukna

Abstract.

In 1957 Markov proved that every circuit on  n  variables can be simulated by a circuit with at most  log (n+1)  negations. In 1974 Fisher has shown that this can be done by only polynomial increase in size. Thus, any function in NP which cannot be computed by a circuit with this number of negations in polynomial size would separate P from NP.

In this note we observe that some explicit monotone functions in P cannot be computed by a circuit of polynomial size if we allow only  log n-O(loglog n)  negations.