Quantum computing records detail what and how precisely to keep
Sufficient quantum provenance: retained fields and certified recording precision
Emerging Technologies
Summary
Quantum computers run complex calculations but understanding their output depends on what internal details are recorded and how precisely. The authors provide a way to know which parts of a quantum computation’s internal process need to be kept to confidently compare results later. They prove this by using certain mathematical distances and apply it to a common quantum algorithm, showing exactly how detailed the recording must be. They also tested real quantum processors, finding the minimal number of labels needed to distinguish different outcomes reliably. This work helps clarify how to store quantum computation details that matter for verifying tasks.
What this means in practice
- •For quantum hardware developers: Determine minimal recording detail needed to certify outputs of quantum processors under noise conditions.
- •For quantum algorithm engineers: Design comparison records that guarantee reliable task outcomes for quantum algorithms like QAOA across noise variations.
Authors
George Kourousias, Sergio Carrato, Roberto Pugliese, Aljoša Hafner, Francesco Guzzi, Matteo Billè, Fulvio Billè, Panagiotis Dimitrakis
Abstract
Which execution details must a quantum computation retain, and to what precision, to support a declared comparison? We define a sufficient record by the largest Hellinger distance between outcome laws that share it. Our main result is a circuit-derived certificate for continuous recording precision: independent channel-mixture probabilities enter through the affinity of latent noise flags, while coherent rotation differences enter through conditional quantum fidelity. Their joint composition bounds whole record cells without simulating their outcome distributions. For four-qubit QAOA at depth one, a 13-bit comparison record guarantees distance below 0.05 throughout a declared continuous noise box, uniformly over programmed angles when comparisons hold the logical task fixed. A construction with observable noise flags attains the general bound. Exact tensorization of Hellinger affinity connects recording precision to the length of a future measurement transcript. On finite context classes, separation witnesses certify minimum-cost field retention; a four-field record is the unique minimum for 28 archived QAOA instances. Fresh six-qubit processor measurements establish different minimum label counts at one common tolerance: two labels are necessary and sufficient for raw laws, while one suffices after a fixed decoder for a synthetic image-segmentation task. These hardware conclusions are conditional on stationary independent shots and remain distinct from the analytic channel certificate. Shared task definitions and evidential archives are retained separately. The framework specifies which execution distinctions matter, how precisely to record them, and what evidence supports the resulting agreement guarantee.