It is established a linear (thereby, sharp) lower bound on degrees of Positivstellensatz calculus refutations over a real eld introduced in GV99], for the Tseitin tautologies and for the parity (the mod 2 principle). We use the machinery of the Laurent proofs developped for binomial systems in BuGI 98], BuGI 99].
This paper gives nearly optimal lower bounds on the minimum degree of polynomial calculus refutations of Tseitin's graph tautologies and the mod p counting principles, p 2. The lower bounds apply to the polynomial calculus over elds or rings. These are the rst linear lower bounds for polynomial calculus; moreover, they distinguish linearly between proofs… (More)
We introduce two versions of proof systems dealing with systems of inequalities: Positivstellensatz refutations and Positivstellensatz calculus. For both systems we prove the lower bounds on degrees and lengths of derivations for the example due to Lazard, Mora and Philip-pon. These bounds are sharp, as well as they are for the Nullstellen-satz refutations… (More)
It is established a lower bound on degrees of Positivstellensatz calculus refutations (over a real eld) introduced in GV 99], G 99], for the knapsack problem. The bound depends on the values of co-eecients of an instance of the knapsack problem: for certain values the lower bound is linear and for certain values the upper bound is constant, while in the… (More)
It is a known approach to translate propositional formulas into systems of polynomial inequalities and consider proof systems for the latter. The well-studied proof systems of this type are the Cutting Plane proof system (CP) utilizing linear inequalities and the Lovász– Schrijver calculi (LS) utilizing quadratic inequalities. We introduce generalizations… (More)
The authors consider the problem of reconstructing (i.e., interpolating) a t-sparse multivariate polynomial given a black box which will produce the value of the polynomial for any value of the arguments. It is shown that, if the polynomial has coefficients in a finite field GF[q] and the black box can evaluate the polynomial in the field GF[qr2g,tnt+37],… (More)
It is shown that the problem of deciding and constructing a perfect matching in bipartite graphs G with the polynomial permanents of their n n adjacency matrices A (perm(A) = n O(1)) are in the deterministic classes NC 2 and NC 3 , respectively. We further design an NC 3 algorithm for the problem of constructing all perfect matchings (enumeration problem)… (More)