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arXiv · 2007.05301

Quantum-Mechanical Correlations and Tsirelson Bound from Geometric Algebra

Carsten Held
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Abstract

The Bell-Clauser-Horne-Shimony-Holt inequality can be used to show that no local hidden-variable theory can reproduce the correlations predicted by quantum mechanics (QM). It can be proved that certain QM correlations lead to a violation of the classical bound established by the inequality, while all correlations, QM and classical, respect a QM bound (the Tsirelson bound). Here, we show that these well-known results depend crucially on the assumption that the values of physical magnitudes are scalars. The result implies, first, that the origin of the Tsirelson bound is geometrical, not physical; and, second, that a local hidden-variable theory does not contradict QM if the values of physical magnitudes are vectors.

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Carsten Held. 2020-07-10. Quantum-Mechanical Correlations and Tsirelson Bound from Geometric Algebra. https://doi.org/10.1007/s40509-021-00252-y

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