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arXiv · 2402.02585

Grover-QAOA for 3-SAT: Quadratic Speedup, Fair-Sampling, and Parameter Clustering

Zewen Zhang·Roger Paredes·Bhuvanesh Sundar·David Quiroga·Anastasios Kyrillidis·Leonardo Duenas-Osorio·Guido Pagano·Kaden R. A. Hazzard
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Abstract

The SAT problem is a prototypical NP-complete problem of fundamental importance in computational complexity theory with many applications in science and engineering; as such, it has long served as an essential benchmark for classical and quantum algorithms. This study shows numerical evidence for a quadratic speedup of the Grover Quantum Approximate Optimization Algorithm (G-QAOA) over random sampling for finding all solutions to 3-SAT problems (All-SAT). G-QAOA is less resource-intensive and more adaptable for 3-SAT and Max-SAT than Grover's algorithm, and it surpasses conventional QAOA in its ability to sample all solutions. We show these benefits by classical simulations of many-round G-QAOA on thousands of random 3-SAT instances. We also observe G-QAOA advantages on the IonQ Aria quantum computer for small instances, finding that current hardware suffices to determine and sample all solutions. Interestingly, a single-angle-pair constraint that uses the same pair of angles at each G-QAOA round greatly reduces the classical computational overhead of optimizing the G-QAOA angles while preserving its quadratic speedup. We also find parameter clustering of the angles. The single-angle-pair protocol and parameter clustering significantly reduce obstacles to classical optimization of the G-QAOA angles.

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Zewen Zhang, Roger Paredes, Bhuvanesh Sundar, David Quiroga, Anastasios Kyrillidis, Leonardo Duenas-Osorio, Guido Pagano, Kaden R. A. Hazzard. 2024-02-04. Grover-QAOA for 3-SAT: Quadratic Speedup, Fair-Sampling, and Parameter Clustering. https://doi.org/10.1088/2058-9565%2Fad895c

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