arXiv:2512.15476 · v2
QuantGraph: A Receding-Horizon Quantum Graph Solver
摘要
Dynamic programming is a cornerstone of graph-based optimization. While effective, it scales unfavorably with problem size. In this work, we present QuantGraph, a two-stage quantum-enhanced framework that casts local and global graph-optimization problems as quantum-searches over discrete trajectory spaces. The solver is designed to operate efficiently by first finding a sequence of locally optimal transitions in the graph (local stage), without considering full trajectories. The accumulated cost of the resulting candidate acts as a threshold that prunes the search space (up to 60% reduction for certain examples). The subsequent global stage, based on this threshold, refines the solution. To achieve scalability and robustness, we draw on principles from control theory and embed QuantGraph's global stage within a receding-horizon model-predictive-control scheme. This classical layer stabilizes and guides the quantum search, improving precision and reducing computational burden. In practice, the resulting closed-loop system exhibits robust behavior and lower query complexity. Notably, for a fixed control horizon and query budget, QuantGraph supports approximately twice as many control discretization bits while still benefiting from Grover-search's inherent quadratic speedup compared to classical methods.
作者备注：P. Vaidhyanathan and A. Papatheodorou contributed equally to this work. Published in Physical Review Applied. 17 pages, 4 figures, 2 tables, 2 algorithms