Truth Assignments as Conditional Autarkies

Summary

An autarky for a formula in propositional logic is a truth assignment that satisfies every clause it touches, i.e., every clause for which the autarky assigns at least one variable. In this paper, we present how conditional autarkies, a generalization of autarkies, give rise to novel preprocessing techniques for SAT solving. We show that conditional autarkies correspond to a new type of redundant clauses, termed globally-blocked clauses, and that the elimination of these clauses can simulate existing circuit-simplification techniques on the CNF level.