Optimal Measurements of Spin Direction

  title={Optimal Measurements of Spin Direction},
  author={David Marcus Appleby},
  journal={International Journal of Theoretical Physics},
  • D. M. Appleby
  • Published 5 November 1999
  • Mathematics, Physics
  • International Journal of Theoretical Physics
The accuracy of a measurement of the spin direction of a spin-s particle ischaracterized for arbitrary half-integral s. The disturbance caused by themeasurement is also characterized. The approach is based on that taken in severalprevious papers concerning joint measurements of position and momentum. Asin those papers, a distinction is made between the errors of retrodiction andprediction. Retrodictive and predictive error relationships are derived. The POVMdescribing the outcome of a maximally… Expand
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Int. J. Theor. Phys
  • Int. J. Theor. Phys
  • 1998
Commun. Math. Phys
  • Commun. Math. Phys
  • 1973
Proc. Phys. Math. Soc. Japan
  • Proc. Phys. Math. Soc. Japan
  • 1940