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arXiv · 2104.11909

Quantum Disturbance without State Change: Soundness and Locality of Disturbance Measures

Masanao Ozawa
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Abstract

It is often supposed that a quantum system is not disturbed without state change. In a recent debate, this assumption is used to claim that the operator-based disturbance measure, a broadly used disturbance measure, has an unphysical property. Here, we show that a quantum system possibly incurs an operationally detectable disturbance without state change to rebut the claim. Moreover, we establish the reliability, formulated as soundness and locality, of the operator-based disturbance measure, which, we show, quantifies the disturbance on an observable that manifests in the time-like correlation even in the case where its probability distribution does not change.

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Masanao Ozawa. 2021-04-24. Quantum Disturbance without State Change: Soundness and Locality of Disturbance Measures. https://arxiv.org/abs/2104.11909

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