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arXiv · 1005.0569

Position Measurements Obeying Momentum Conservation

Paul Busch·Leon Loveridge
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Abstract

We present a hitherto unknown fundamental limitation to a basic measurement: that of the position of a quantum object when the total momentum of the object and apparatus is conserved. This result extends the famous Wigner-Araki-Yanase (WAY) theorem, and shows that accurate position measurements are only practically feasible if there is a large momentum uncertainty in the apparatus.

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Paul Busch, Leon Loveridge. 2011-02-24. Position Measurements Obeying Momentum Conservation. https://doi.org/10.1103/physrevlett.106.110406

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