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arXiv · 2107.08975

Macroscopic features of quantum fluctuations in large N qubit system

Andrei B. Klimov·Carlos Munoz
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Abstract

We introduce a discrete Q-function of N qubit system projected into the space of symmetric measurements as a tool for analyzing general properties of quantum systems in the macroscopic limit. For known states the projected Q-function helps to visualize the results of collective measurements, and for unknown states it can be approximately reconstructed by measuring lowest moments of the of collective variables.

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Andrei B. Klimov, Carlos Munoz. 2021-07-19. Macroscopic features of quantum fluctuations in large N qubit system. https://doi.org/10.1103/physreva.89.052130

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