Goto

Collaborating Authors

 canonical logic program


Canonical Logic Programs are Succinctly Incomparable with Propositional Formulas

AAAI Conferences

Canonical (logic) programs (CP) refer to the class of normal programs (LP) augmented with connective not not , and  are equally expressive as propositional formulas (PF). In this paper we address the question of whether CP and PF are succinctly incomparable. Our main result shows that the PARITY problem only has exponential CP representations, while it can be polynomially represented in PF.  In other words, PARITY separates PF from CP. Simply speaking, this means that exponential size blowup is generally inevitable  when  translating a set of PF formulas into a (logically) equivalent CP program (without introducing new variables). Furthermore,  since it has been shown by Lifschitz and  Razborov  that there is also a problem which separates CP from PF (assuming P ⊈ NC 1 poly), it follows that the two formalisms are indeed succinctly incomparable.