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arXiv · 2510.08239

Operational protocols cannot certify classicality

Chris Fields·James F. Glazebrook·Antonino Marcianò·Emanuele Zappala
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Abstract

The existence and practical utility of operational protocols that certify entanglement raises the question of whether operational protocols exist that certify the absence of entanglement, i.e. that certify separability. We show, within a purely topological, interpretation-independent representation, that such protocols do not exist. Classicality is therefore, as Bohr suggested, purely a pragmatic notion.

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Chris Fields, James F. Glazebrook, Antonino Marcianò, Emanuele Zappala. 2025-10-09. Operational protocols cannot certify classicality. https://arxiv.org/abs/2510.08239

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