Foundations of Physics

, Volume 39, Issue 7, pp 712–730 | Cite as

On the Sharpness and Bias of Quantum Effects



The question of quantifying the sharpness (or unsharpness) of a quantum mechanical effect is investigated. Apart from sharpness, another property, bias, is found to be relevant for the joint measurability or coexistence of two effects. Measures of bias will be defined and examples given.


Quantum measurement Joint observable Coexistence Effect Unsharp observable Bias 


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© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of MathematicsUniversity of YorkYorkUK

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