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An R||C_{max} Quantum Scheduling Algorithm

Feng Lu·Dan C. Marinescu
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Abstract

Grover's search algorithm can be applied to a wide range of problems; even problems not generally regarded as searching problems, can be reformulated to take advantage of quantum parallelism and entanglement, and lead to algorithms which show a square root speedup over their classical counterparts. In this paper, we discuss a systematic way to formulate such problems and give as an example a quantum scheduling algorithm for an $R||C_{max}$ problem. $R||C_{max}$ is representative for a class of scheduling problems whose goal is to find a schedule with the shortest completion time in an unrelated parallel machine environment. Given a deadline, or a range of deadlines, the algorithm presented in this paper allows us to determine if a solution to an $R||C_{max}$ problem with $N$ jobs and $M$ machines exists, and if so, it provides the schedule. The time complexity of the quantum scheduling algorithm is $\mathcal{O}(\sqrt{M^N})$ while the complexity of its classical counterpart is $\mathcal{O}(M^N)$.

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Feng Lu, Dan C. Marinescu. 2006-09-29. An R||C_{max} Quantum Scheduling Algorithm. https://arxiv.org/abs/quant-ph/0511028

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