Hiding Solutions in Random Satisfiability Problems: A Statistical Mechanics Approach

W. Barthel, A. K. Hartmann, M. Leone, F. Ricci-Tersenghi, M. Weigt, R. Zecchina
2002 Physical Review Letters  
A major problem in evaluating stochastic local search algorithms for NP-complete problems is the need for a systematic generation of hard test instances having previously known properties of the optimal solutions. On the basis of statistical mechanics results, we propose random generators of hard and satisfiable instances for the 3-satisfiability problem (3SAT). The design of the hardest problem instances is based on the existence of a first order ferromagnetic phase transition and the glassy
more » ... ture of excited states. The analytical predictions are corroborated by numerical results obtained from complete as well as stochastic local algorithms.
doi:10.1103/physrevlett.88.188701 pmid:12005728 fatcat:lbqrp62sgjhlrjf5bhnamgzgyi