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Conservation laws, uncertainty relations, and quantum limits of measurements

Masanao Ozawa
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Abstract

The uncertainty relation between the noise operator and the conserved quantity leads to a bound for the accuracy of general measurements. The bound extends the assertion by Wigner, Araki, and Yanase that conservation laws limit the accuracy of ``repeatable'', or ``nondisturbing'', measurements to general measurements, and improves the one previously obtained by Yanase for spin measurements. The bound also sets an obstacle to making a small quantum computer.

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Masanao Ozawa. 2001-12-24. Conservation laws, uncertainty relations, and quantum limits of measurements. https://doi.org/10.1103/physrevlett.88.050402

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