On the Ohya-Masuda Quantum SAT Algorithm

Marcos Alemany Manzanaro, Higinio Mora

Charles Varmantchaonala Moudina, Jean Louis Ebongue Kedieng Fendji, J.-P. Tchapet Njafa +1 more

M. Dugić

We analyze the Ohya-Masuda quantum algorithm that solves the so-called “satisfiability” problem, which is an NP-complete problem of the complexity theory. We distinguish three steps in the algorithm, and analyze the second step, in which a coherent superposition of states (a “pure” state) transforms into an “incoherent” mixture presented by a density matrix. We show that, if “nonideal” (in analogy with “nonideal” quantum measurement), this transformation can make the algorithm to fail in some cases. On this basis we give some general notions on the physical implementation of the Ohya-Masuda algorithm.

Charles Varmantchaonala Moudina, Jean Louis Ebongue Kedieng Fendji, J.-P. Tchapet Njafa +1 more

Shigeo Akashi, Satoshi Iriyama

Ohya and Volovich have been proposed a new quantum computation model with chaos amplification to solve the SAT problem, which went beyond usual quantum algorithm. In this paper we study the complexity of the SAT algorithm by counting the steps of computation algorithm rigorously, which was mentioned in the paper [1,2,3,5,7]For this purpose, we refine the quantum gates treating the SAT problem step by step.

Satoshi Iriyama, Masanori Ohya

For SAT problem, which is known to be NP-complete, Ohya and Masuda found a quantum algorithm calculating a given boolean function for all truth assignments. They showed that we can decide whether this boolean function is satisfiable or not in polynomial time if a certain superposed state can be detected physically, which turns out to be related to an amplification process. Then Ohya and Volovich realized this amplification by means of chaos dynamics [4, 5]. In this paper, we study the complexity of the SAT algorithm by rigorously counting the steps of OMV algorithm discussed previously in [1, 2, 4, 5].