Position Measurements Obeying Momentum Conservation

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.

References in corpus (2)

• Reference frames, superselection rules, and quantum information
• Intrinsic unsharpness and approximate repeatability of quantum measurements

Cited by in corpus (1)

• 'Measurement of Quantum Mechanical Operators' Revisited