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arXiv · 2202.05553

On characterising assemblages in Einstein-Podolsky-Rosen scenarios

Vinicius P. Rossi·Matty J. Hoban·Ana Belén Sainz
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Abstract

Characterising non-classical quantum phenomena is crucial not only from a fundamental perspective, but also to better understand its capabilities for information processing and communication tasks. In this work, we focus on exploring the characterisation of Einstein-Podolsky-Rosen inference (a.k.a. steering): a signature of non-classicality manifested when one or more parties in a Bell scenario have their systems and measurements described by quantum theory, rather than being treated as black boxes. We propose a way of characterising common-cause assemblages from the correlations that arise when the trusted party performs tomographically-complete measurements on their share of the experiment, and discuss the advantages and challenges of this approach. Within this framework, we show that so-called almost quantum assemblages satisfy the principle of macroscopic noncontextuality, and demonstrate that a subset of almost quantum correlations recover almost quantum assemblages in this approach.

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Vinicius P. Rossi, Matty J. Hoban, Ana Belén Sainz. 2022-02-11. On characterising assemblages in Einstein-Podolsky-Rosen scenarios. https://doi.org/10.1088/1751-8121%2Fac7090

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