Global Completability with Applications to Self-Consistent Quantum Tomography
Cyril Stark
备注:
In the new version we focus entirely on the geometric problem described in the abstract. Proofs are more detailed and hopefully more transparent. To make contact with the literature on related questions, we talk about completability instead of rigidity. However, we had to remove the discussion of projective non-degenerate measurements. This investigation is better embedded in another manuscript
Let p_1, ..., p_N \in R^D be unknown vectors and let Omega \subseteq {1,...,N}^{\times 2}. Assume that the inner products p_i^T p_j are fixed for all (i,j) \in Omega. Do these inner product constraints (up to simultaneous rotation of all vectors) determine p_1, ..., p_N uniquely? Here we derive a necessary and sufficient condition for the uniqueness of p_1, ...,p_N (i.e., global completability) which is applicable to a large class of practically relevant sets Omega. Moreover, given Omega, we show that the condition for global completability is universal in the sense that for almost all vectors p_1, ...,p_N \in R^D the completability of p_1, ...,p_N only depends on Omega and not on the specific values of p_i^T p_j$ for (i,j) \in Omega. This work was motivated by practical considerations, namely, self-consistent quantum tomography.
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École Polytechnique Fédérale de Lausanne (EPFL)(洛桑联邦理工学院);Joint Quantum Institute, NIST/University of Maryland(美国国家标准与技术研究院/马里兰大学联合量子研究所);Joint Center for Quantum Information and Computer Science, NIST/University of Maryland(美国国家标准与技术研究院/马里兰大学联合量子信息与计算科学中心);Freie Universität Berlin(柏林自由大学)
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CONNECT Research Centre, School of Engineering, Trinity College Dublin(都柏林三一学院工程学院连接研究中心);Manning College of Information and Computer Science, University of Massachusetts Amherst(马萨诸塞大学阿默斯特分校曼宁信息与计算机科学学院);Department of Computing, School of Science, South East Technological University(东南理工大学理学院计算系)
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College of Physics, Sichuan University(四川大学物理学院);Department of Physics and Hong Kong Institute of Quantum Science and Technology, The University of Hong Kong(香港大学物理系及香港量子科学研究所);School of Physics Science and Engineering, Tongji University(同济大学物理科学与工程学院);Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology(南方科技大学深圳量子科学与工程研究院);International Quantum Academy(国际量子科学院);Guangdong Provincial Key Laboratory of Quantum Science and Engineering, Southern University of Science and Technology(南方科技大学广东省量子科学与工程重点实验室);Institute for Advanced Study, Tsinghua University(清华大学高等研究院);Hefei National Laboratory(合肥国家实验室);Department of Physics, University of California at San Diego(加州大学圣地亚哥分校物理系);Department of Physics & State Key Laboratory of Surface Physics, Fudan University(复旦大学物理系及表面物理国家重点实验室);Shanghai Qi Zhi Institute(上海人工智能实验室)
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ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology(光子科学研究所,巴塞罗那科技研究所);Centre for Quantum Technologies, National University of Singapore(量子技术中心,新加坡国立大学);Quantum Research Center, Technology Innovation Institute(量子研究中心,技术创新研究院);Department of Quantum Information and Computation at Kepler (QUICK), Johannes Kepler University Linz(开普勒量子信息与计算系,约翰内斯·开普林茨大学)