Upper and Lower Bounds for Tree-Like Cutting Planes Proofs
نویسندگان
چکیده
In this paper we study the complexity of Cutting Planes (CP) refutations, and tree-like CP refutations. Tree-like CP proofs are natural and still quite powerful. In particular, the propositional pigeonhole principle (PHP) has been shown to have polynomial-sized tree-like CP proofs. Our main result shows that a family of tautologies, introduced in this paper requires exponential-sized tree-like CP proofs. We obtain this result by introducing a new method which relates the size of a CP refutation to the communication complexity of a related search problem. Because these tautologies have polynomial-sized Frege proofs, it follows that tree-like CP cannot polynomially simulate Frege systems.
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