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arXiv · 2604.14319

Warring Contextualities - Provably Classical vs Provably Nonclassical

Enrico Bozzetto·Jonte R. Hance
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Abstract

In the literature, there are two differing definitions of contextuality: Kochen and Specker's, and Spekkens' (or ``generalised''). However, researchers using one of these definitions rarely consider the other, meaning comparative analysis of these two notions is rare. In this paper, we advance the idea that Kochen-Specker contextuality provides a generalisation of the idea of system being fundamentally \emph{nonclassical}, while Spekkens' noncontextuality provides a generalisation of the idea of a system being \emph{classical}. This allows us to reconcile the two approaches, as different stages in a hierarchy of classicality/nonclassicality.

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Enrico Bozzetto, Jonte R. Hance. 2026-04-15. Warring Contextualities - Provably Classical vs Provably Nonclassical. https://arxiv.org/abs/2604.14319

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