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Joint measurements of spin, operational locality and uncertainty

Erika Andersson·Stephen M. Barnett·Alain Aspect
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Abstract

Joint, or simultaneous, measurements of non-commuting observables are possible within quantum mechanics, if one accepts an increase in the variances of the jointly measured observables. In this paper, we discuss joint measurements of a spin 1/2 particle along any two directions. Starting from an operational locality principle, it is shown how to obtain a bound on how sharp the joint measurement can be. We give a direct interpretation of this bound in terms of an uncertainty relation.

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Erika Andersson, Stephen M. Barnett, Alain Aspect. 2005-09-21. Joint measurements of spin, operational locality and uncertainty. https://doi.org/10.1103/physreva.72.042104

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