Improved Lower Bounds for Tree-Like Resolution over Linear Inequalities
نویسنده
چکیده
We continue a study initiated by Kraj́ıček of a Resolutionlike proof system working with clauses of linear inequalities, R(CP). For all proof systems of this kind Kraj́ıček proved in [1] an exponential lower bound of the form: exp(n) MO(W log2 n) , where M is the maximal absolute value of coefficients in a given proof and W is the maximal clause width. In this paper we improve this lower bound. For tree-like R(CP)-like proof systems we remove a dependence on the maximal absolute value of coefficients M , hence, we give the answer to an open question from [2]. Proof follows from an upper bound on the real communication complexity of a polyhedra.
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