A hybrid quantum-classical approach to warm-starting optimization

TL;DR

This paper compares standard and warm-start QAOA for portfolio optimization, revealing that classical preprocessing can replicate or outperform quantum-enhanced approaches, questioning the quantum advantage.

Contribution

It demonstrates that classical preprocessing can match or exceed warm-start QAOA performance, challenging the presumed quantum advantage in this context.

Findings

Warm-start QAOA improves optimization performance.

Classical preprocessing can replicate quantum effects.

Quantum advantage may be limited in this setting.

Abstract

The Quantum Approximate Optimization Algorithm (QAOA) is a promising candidate for solving combinatorial optimization problems more efficiently than classical computers. Recent studies have shown that warm-starting the standard algorithm improves the performance. In this paper we compare the performance of standard QAOA with that of warm-start QAOA in the context of portfolio optimization and investigate the warm-start approach for different problem instances. In particular, we analyze the extent to which the improved performance of warm-start QAOA is due to quantum effects, and show that the results can be reproduced or even surpassed by a purely classical preprocessing of the original problem followed by standard QAOA.