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arXiv · 2104.05734

Emergence of noncontextuality under quantum Darwinism

Roberto D. Baldijão·Rafael Wagner·Cristhiano Duarte·Bárbara Amaral·Marcelo Terra Cunha
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Abstract

Quantum Darwinism proposes that the proliferation of redundant information plays a major role in the emergence of objectivity out of the quantum world. Is this kind of objectivity necessarily classical? We show that if one takes Spekkens' notion of noncontextuality as the notion of classicality and the approach of Brand\~{a}o, Piani and Horodecki to quantum Darwinism, the answer to the above question is `yes', if the environment encodes sufficiently well the proliferated information. Moreover, we propose a threshold on this encoding, above which one can unambiguously say that classical objectivity has emerged under quantum Darwinism.

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Roberto D. Baldijão, Rafael Wagner, Cristhiano Duarte, Bárbara Amaral, Marcelo Terra Cunha. 2021-04-12. Emergence of noncontextuality under quantum Darwinism. https://doi.org/10.1103/prxquantum.2.030351

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