arXiv:1005.0569 · Physical Review Letters

Position Measurements Obeying Momentum Conservation

Paul Busch, Leon Loveridge

Published Mar 18, 2011• 32 citations

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 theorem, and shows that accurate position measurements are only practically feasible if there is a large momentum uncertainty in the apparatus.

DOI: 10.1103/physrevlett.106.110406

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