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Quantum Disturbance without State Change: Defense of State-Dependent Error-Disturbance Relations

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 نشر من قبل Masanao Ozawa
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف Masanao Ozawa




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The uncertainty principle states that a measurement inevitably disturbs the system, while it is often supposed that a quantum system is not disturbed without state change. Korzekwa, Jennings, and Rudolph [Phys. Rev. A 89, 052108 (2014)] pointed out a conflict between those two views, and concluded that state-dependent formulations of error-disturbance relations are untenable. Here, we reconcile the conflict by showing that a quantum system is disturbed without state change, in favor of the recently obtained universally valid state-dependent error-disturbance relations.

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