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arXiv · 2205.00198

Temporal witnesses of non-classicality and conservation laws

Giuseppe Di Pietra·Chiara Marletto
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Abstract

A general entanglement-based witness of non-classicality has recently been proposed, which can be applied to testing quantum effects in gravity. This witness is based on generating entanglement between two quantum probes via a mediator. In this paper we provide a "temporal" variant of this witness, using a single quantum probe to assess the non-classicality of the mediator. Within the formalism of quantum theory, we show that if a system $M$ is capable of inducing a coherent dynamical evolution of a quantum system $Q$, in the presence of a conservation law, then $M$ must be non-classical. This argument supports witnesses of non-classicality relying on a single quantum probe, which can be applied to a number of open issues, notably in quantum gravity or quantum biology.

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Giuseppe Di Pietra, Chiara Marletto. 2022-04-30. Temporal witnesses of non-classicality and conservation laws. https://doi.org/10.1088/1751-8121%2Facda6b

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