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Approximating satisfiability transition by suppressing fluctuations

S. Knysh·V. N. Smelyanskiy·R. D. Morris
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Abstract

Using methods and ideas from statistical mechanics, we propose a simple method for obtaining rigorous upper bounds for satisfiability transition in random boolean expressions composed of N variables and M clauses with K variables per clause. Determining the location of satisfiability threshold $α_c=M/N$ for a number of difficult combinatorial problems is a major open problem in the theory of random graphs. The method is based on identification of the core -- a subexpression (subgraph) that has the same satisfiability properties as the original expression. We formulate self-consistency equations that determine macroscopic parameters of the core and compute an improved annealing bound. We illustrate the method for three sample problems: K-XOR-SAT, K-SAT and positive 1-in-K-SAT.

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S. Knysh, V. N. Smelyanskiy, R. D. Morris. 2004-03-17. Approximating satisfiability transition by suppressing fluctuations. https://arxiv.org/abs/cond-mat/0403416

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