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arXiv · 2102.06581

Post-quantum steering is a stronger-than-quantum resource for information processing

Paulo J. Cavalcanti·John H. Selby·Jamie Sikora·Thomas D. Galley·Ana Belén Sainz
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Abstract

We present the first instance where post-quantum steering is a stronger-than-quantum resource for information processing -- remote state preparation. In addition, we show that the phenomenon of post-quantum steering is not just a mere mathematical curiosity allowed by the no-signalling principle, but it may arise within compositional theories beyond quantum theory, hence making its study fundamentally relevant. We show these results by formulating a new compositional general probabilistic theory -- which we call Witworld -- with strong post-quantum features, which proves to be a intuitive and useful tool for exploring steering and its applications beyond the quantum realm.

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Paulo J. Cavalcanti, John H. Selby, Jamie Sikora, Thomas D. Galley, Ana Belén Sainz. 2022-07-13. Post-quantum steering is a stronger-than-quantum resource for information processing. https://doi.org/10.1038/s41534-022-00574-8

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