Blind delegation protocols allow a client to delegate a computation to a server so that the server learns nothing about the input to the computation apart from its size. For the specific case of quantum computation we know that blind delegation protocols can achieve information-theoretic security. In this paper we prove, provided certain complexity-theoretic conjectures are true, that the power of information-theoretically secure blind delegation protocols for quantum computation (ITS-BQC protocols) is in a number of ways constrained. In the first part of our paper we provide some indication that ITS-BQC protocols for delegating $\sf BQP$ computations in which the client and the server interact only classically are unlikely to exist. We first show that having such a protocol with $O(n^d)$ bits of classical communication implies that $\mathsf{BQP} \subset \mathsf{MA/O(n^d)}$. We conjecture that this containment is unlikely by providing an oracle relative to which $\mathsf{BQP} \not\subset \mathsf{MA/O(n^d)}$. We then show that if an ITS-BQC protocol exists with polynomial classical communication and which allows the client to delegate quantum sampling problems, then there exist non-uniform circuits of size $2^{n - \mathsfΩ(n/log(n))}$, making polynomially-sized queries to an $\sf NP^{NP}$ oracle, for computing the permanent of an $n \times n$ matrix. The second part of our paper concerns ITS-BQC protocols in which the client and the server engage in one round of quantum communication and then exchange polynomially many classical messages. First, we provide a complexity-theoretic upper bound on the types of functions that could be delegated in such a protocol, namely $\mathsf{QCMA/qpoly \cap coQCMA/qpoly}$. Then, we show that having such a protocol for delegating $\mathsf{NP}$-hard functions implies $\mathsf{coNP^{NP^{NP}}} \subseteq \mathsf{NP^{NP^{PromiseQMA}}}$.
Verifier-on-a-Leash: new schemes for verifiable delegated quantum computation, with quasilinear resources
可靠地证明量子设备执行的计算结果的问题正在迅速获得相关性。我们提出了两个协议的经典验证可验证的量子计算委托给两个非通信，但纠缠的量子证明。我们的协议具有接近最优的复杂性，在验证者和诚实证明者所使用的总资源方面，每一方的操作总数，包括诚实证明者所需的纠缠量子比特对的数量，缩放为$O(g\log g)$，用于委托大小为$g$的电路。这与以前的协议相反，以前的协议都需要非常大的多项式开销。我们的第一个协议需要在被委托的电路的深度上线性的回合数，并且是盲的，这意味着两个证明者都不能学习被委托的电路。第二个协议不是盲目的，但只需要恒定数量的交互轮数。我们的主要技术创新是一个有效的刚性定理，它允许验证器测试，两个纠缠的证明者执行测量指定的任意$m$ -量子位张量积的单量子位克利福德观测值在各自的一半的$m$共享EPR对，具有鲁棒性，是独立的$m$。我们的两个证明者经典验证者委托协议是通过将这个刚性定理与Broadbent（Theory of Computing，2018）介绍的用于量子计算的可验证委托的单证明者量子验证者协议相结合而获得的。
Private Delegated Quantum Computing for User-Level and Industry-Level Settings
Instituto Tecnológico de Castilla y León（卡斯蒂利亚和莱昂理工学院）；National University of San Marcos（圣马科斯国立大学）；Universidad Nacional del Comahue（科马韦国立大学）；Thinkcomm SRL（Thinkcomm有限公司）
Simulation of Two-Qubit Grover Algorithm in MBQC with Universal Blind Quantum Computation
Electronics and Telecommunications Research Institute (ETRI)（电子电信研究所）；Cryptography Engineering Laboratory, Electronics and Telecommunications Research Institute (ETRI)（电子电信研究所密码工程实验室）
Plugging Leaks in Fault-Tolerant Quantum Computation and Verification
National Quantum Computing Centre, Rutherford Appleton Laboratory（拉瑟福德·阿普尔顿实验室国家量子计算中心）；School of Informatics, University of Edinburgh（爱丁堡大学信息学院）；Quandela；Département d’Informatique, Ecole Normale Supérieure（巴黎高等师范学院计算机科学系）
Partially-Blind Single-Qubit Classification over a Prototype Hybrid Quantum Network
ICFO—Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology（光子科学研究所，巴塞罗那科学与技术研究院）；LION—Leiden Institute of Physics, Leiden University（莱顿物理研究所，莱顿大学）；QuTech, Delft University of Technology（量子技术中心，代尔夫特理工大学）；Kavli Institute of Nanoscience, Delft University of Technology（卡弗里纳米科学研究所，代尔夫特理工大学）；SURF—Collaborating University Computing Facilities（SURF大学计算设施合作组织）；NITeQ—Interdisciplinary Nucleus for Quantum Technologies, PUC-Rio—Pontifical Catholic University of Rio de Janeiro（量子技术跨学科核心机构，里约热内卢天主教大学）；ICREA—Institucio Catalana de Recerca i Estudis Avançats（加泰罗尼亚研究高级学院）；Quantum Technology Department, TNO—The Netherlands Organization for Applied Scientific Research（量子技术部，荷兰应用科学研究组织）
Experimental verifiable multi-client blind quantum computing on a Qline architecture
Dipartimento di Fisica - Sapienza Università di Roma（罗马大学物理系）；School of Informatics, University of Edinburgh（爱丁堡大学信息学院）；VeriQloud；Laboratoire d’Informatique de Paris 6, CNRS, Sorbonne Université（巴黎第六大学计算机实验室，法国国家科学研究中心，索邦大学）
