Given that reliable cloud quantum computers are becoming closer to reality, the concept of delegation of quantum computations and its verifiability is of central interest. Many models have been proposed, each with specific strengths and weaknesses. Here, we put forth a new model where the client trusts only its classical processing, makes no computational assumptions, and interacts with a quantum server in a single round. In addition, during a set-up phase, the client specifies the size $n$ of the computation and receives an untrusted, off-the-shelf (OTS) quantum device that is used to report the outcome of a single measurement. We show how to delegate polynomial-time quantum computations in the OTS model. This also yields an interactive proof system for all of QMA, which, furthermore, we show can be accomplished in statistical zero-knowledge. This provides the first relativistic (one-round), two-prover zero-knowledge proof system for QMA. As a proof approach, we provide a new self-test for n EPR pairs using only constant-sized Pauli measurements, and show how it provides a new avenue for the use of simulatable codes for local Hamiltonian verification. Along the way, we also provide an enhanced version of a well-known stability result due to Gowers and Hatami and show how it completes a common argument used in self-testing.

翻译：鉴于可靠的云量子计算机正逐步成为现实，量子计算的委托概念及其可验证性已成为核心关注点。已有多种模型被提出，各自具有特定的优缺点。本文提出一种新模型：委托方仅信任其经典处理能力，不做任何计算假设，并在一轮交互中与量子服务器通信。此外，在设置阶段，委托方指定计算规模n，并接收一个不可信的、市售量子设备，该设备用于报告单次测量结果。我们展示了如何在市售设备模型中委托多项式时间的量子计算。这同时为整个QMA问题类提供了一个交互式证明系统，并且我们进一步证明该证明系统能以统计零知识方式实现。这为QMA问题类提供了首个相对论性（单轮）、双证明者零知识证明系统。作为证明方法，我们提出了一种仅使用恒定规模泡利测量的n对EPR量子态的新型自检测协议，并展示了如何为基于可模拟编码的局域哈密顿量验证开辟新途径。在此过程中，我们还给出了Gowers-Hatami著名稳定性定理的增强版本，并展示了该版本如何完善自检测中常用的论证方法。