The K-sat problem in a simple limit
نویسندگان
چکیده
The statistical mechanics of the random K-satisfiability (K-SAT) problem has been the object of many studies in the last years [1][2][3]. The K-SAT was the first problem to be shown to be Nondeterministic Polynomial (NP) complete [4] and the importance of such a model is that it provides a prototype for all the NP complete problems in complexity theory of computer science as well as in statistical mechanics of disordered and glassy systems, in computational biology and in other fields. The NP complete are those problems whose solution, or the certainty that they have no solutions, can only be found (in the worst case) by algorithms with a running time of computation that likely grows faster than polynomially (namely exponentially) with the number of variables N of the system. The K-SAT model also allows a basic understanding of the connection between the SAT/UN-SAT phase transition in random combinatorial structures [1][2] and the transition between a Replica Symmetric structure and a structure where the symmetry is broken in the frame of spin-glasses [5]. Yet the question stays open of how exactly the typical-case complexity theory of computer science and the Replica Symmetry Breaking (RSB) transition are related. One of the main aim of the recent research on this model has been to understand better the structure of solutions, above all at the borderline between the region of diagram of phase where the
منابع مشابه
Providing a Simple Method for the Calculation of the Source and Target Reliabili- ty in a Communication Network (SAT)
The source and target reliability in SAT network is de- fined as the flawless transmission from the source node to all the other nodes. In some references, the SAT pro- cess has been followed between all the node pairs but it is very time-consuming in today’s widespread networks and involves many costs. In this article, a method has been proposed to compare the reliability in complex networks b...
متن کاملSatisfiability-based Set Membership Filters
Introduced here is a novel application of Satisfiability (SAT) to the set membership problem with specific focus on efficiently testing whether large sets contain a given element. Such tests can be greatly enhanced via the use of filters, probabilistic algorithms that can quickly decide whether or not a given element is in a given set. This article proposes SAT filters (i.e., filters based on S...
متن کاملProviding a Simple Method for the Calculation of the Source and Target Reliabili- ty in a Communication Network (SAT)
The source and target reliability in SAT network is de- fined as the flawless transmission from the source node to all the other nodes. In some references, the SAT pro- cess has been followed between all the node pairs but it is very time-consuming in today’s widespread networks and involves many costs. In this article, a method has been proposed to compare the reliability in complex networks b...
متن کاملOn the Complexity of k-SAT
The k-SAT problem is to determine if a given k-CNF has a satisfying assignment. It is a celebrated open question as to whether it requires exponential time to solve k-SAT for k 3. Here exponential time means 2 for some $>0. In this paper, assuming that, for k 3, k-SAT requires exponential time complexity, we show that the complexity of k-SAT increases as k increases. More precisely, for k 3, de...
متن کاملA Note on the Use of Independent Sets for the k-SAT Problem
An independent set of variables is one in which no two variables occur in the same clause in a given k-SAT instance. Recently, independent sets have obtained more attention. Due to a simple observation we prove that a k-SAT instance over n variables with independent set of size i can be solved in time O(φ2(k−1)(n− i)) where φk(n) denotes an upper bound on the complexity of solving k-SAT over n ...
متن کامل