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arXiv · 2512.14834

Entanglement without Quantum Mechanics: Operational Constraints on the Quantum Signature

Samuel Schlegel·Borivoje Dakić·Flavio Del Santo
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Abstract

Quantum entanglement is defined as nonseparability of density operators, yet experimental phase-space statistics alone cannot distinguish classical from quantum sources, so classical data can be used to violate en- tanglement inequalities. Imposing uncertainty bounds, or full tomography, can map the same data onto positive, entangled density operators, yielding a hybrid regime in which classical and quantum models coincide. Thus, certifying genuine quantum entanglement requires additional tests, such as Wigner negativity, incompatibility beyond phase-space measurements, or nonlinear dynamics.

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Samuel Schlegel, Borivoje Dakić, Flavio Del Santo. 2026-09-16. Entanglement without Quantum Mechanics: Operational Constraints on the Quantum Signature. https://doi.org/10.1103/xdz9-x3zj

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