Generic appearance of objective results in quantum measurements
J. K. Korbicz, E. A. Aguilar, P. Ćwikliński, P. Horodecki
备注：
15 pages, 2 figures, v2: typos corrected, v3: improved proof of the main result; added comments on non-Markovianity , v4: title change; published version
Measurement is of central interest in quantum mechanics as it provides the link between the quantum world and the world of everyday experience. One of the features of the latter is its robust, objective character, contrasting the delicate nature of quantum systems. Here we analyze in a completely model-independent way the celebrated von Neumann measurement process, using recent techniques of information flow, studied in open quantum systems. We show the generic appearance of objective results in quantum measurements, provided we macroscopically coarse-grain the measuring apparatus and wait long enough. To study genericity, we employ the widely-used Gaussian Unitary Ensemble of random matrices and the Hoeffding inequality. We derive generic objectivization timescales, given solely by the interaction strength and the systems' dimensions. Our results are manifestly universal and are a generic property of von Neumann measurements.
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Systems Research Institute, Polish Academy of Sciences（波兰科学院系统研究所）；Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences（波兰科学院尼古拉·哥白尼天文学中心）；Center of Excellence in Artificial Intelligence, AGH University（AGH大学人工智能卓越中心）；Faculty of Physics, University of Warsaw（华沙大学物理学院）；Faculty of Physics and Applied Informatics, University of Lodz（罗兹大学物理与应用信息学院）；Departament de Física, Universitat de les Illes Balears（巴利阿里群岛大学物理系）；CRISP – Centre de Recerca Independent de sa Pobla（萨波布拉独立研究中心）
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Equilibration of objective observables in a dynamical model of quantum measurements
University of Bristol（布里斯托大学）；Heriot-Watt University（赫瑞瓦特大学）；Technische Universität Wien（维也纳工业大学）；Atominstitut, Technische Universität Wien（维也纳工业大学原子研究所）；Institute for Quantum Optics and Quantum Information—IQOQI Vienna, Austrian Academy of Sciences（奥地利科学院维也纳量子光学与量子信息研究所）
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