Machine Learning Framework for Efficient Prediction of Quantum Wasserstein Distance
Changchun Feng, Xinyu Qiu, Laifa Tao, Lin Chen
TL;DR
The paper tackles the computational bottleneck of the quantum Wasserstein distance $W_1$ by introducing a data-driven framework that leverages physically meaningful features from quantum state pairs. It systematically compares neural networks and tree-based methods, with Random Forests delivering near-perfect predictions (e.g., $R^2=0.9999$ and MAE~$10^{-5}$ for 3-qubit systems) and tree ensembles outperforming other approaches across 2–4 qubits. The authors validate theoretical propositions in quantum information theory using ML-predicted $W_1$ distances, demonstrating reliable, scalable verification of measurement-probability bounds and gate-error-rate bounds, thereby enabling real-time quantum circuit assessment in NISQ devices. Beyond prediction, the work provides insights into feature importance (Pauli-based measurements dominate) and highlights the potential of ML-guided theory validation and error-correction design. This framework paves the way for fast, scalable quantification of local distinguishability in quantum operations, with practical impact on quantum circuit optimization and fault-tolerant protocol development.
Abstract
The quantum Wasserstein distance (W-distance) is a fundamental metric for quantifying the distinguishability of quantum operations, with critical applications in quantum error correction. However, computing the W-distance remains computationally challenging for multiqubit systems due to exponential scaling. We present a machine learning framework that efficiently predicts the quantum W-distance by extracting physically meaningful features from quantum state pairs, including Pauli measurements, statistical moments, quantum fidelity, and entanglement measures. Our approach employs both classical neural networks and traditional machine learning models. On three-qubit systems, the best-performing Random Forest model achieves near-perfect accuracy ($R^2 = 0.9999$) with mean absolute errors on the order of $10^{-5}$. We further validate the framework's practical utility by successfully verifying two fundamental theoretical propositions in quantum information theory: the bound on measurement probability differences between unitary operations and the $W_1$ gate error rate bound. The results establish machine learning as a viable and scalable alternative to traditional numerical methods for W-distance computation, with particular promise for real-time quantum circuit assessment and error correction protocol design in NISQ devices.
