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A Kochen-Specker Theorem for Unsharp Spin 1 Observables

Thomas Breuer
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Abstract

Unsharp spin observables are shown to arise from the fact that a residual uncertainty about the actual alignment of the measurement device remains. If the uncertainty is below a certain level, and if the distribution misalignments is covariant under rotations, a Kochen-Specker theorem for the unsharp spin observables follows: There are finite sets of directions such that not all the unsharp spin observables in these directions can consistently be assigned approximate truth-values in a non-contextual way.

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Thomas Breuer. 2002-03-20. A Kochen-Specker Theorem for Unsharp Spin 1 Observables. https://arxiv.org/abs/quant-ph/0203103

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