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arXiv · 2003.07974

Witnessing non-classicality beyond quantum theory

Chiara Marletto·Vlatko Vedral
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Abstract

We propose a general argument to show that if a physical system can mediate locally the generation of entanglement between two quantum systems, then it itself must be non-classical. Remarkably, we do not assume any classical or quantum formalism to describe the mediating physical system: our result follows from general information-theoretic principles, drawn from the recently proposed constructor theory of information. This argument provides the indispensable theoretical basis for recently proposed tests of non-classicality in gravity, based on witnessing gravitationally-induced entanglement in quantum probes.

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Chiara Marletto, Vlatko Vedral. 2020-03-17. Witnessing non-classicality beyond quantum theory. https://doi.org/10.1103/physrevd.102.086012

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