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arXiv · 1805.12126

Universal structure of objective states in all fundamental causal theories

Carlo Maria Scandolo·Roberto Salazar·Jarosław K. Korbicz·Paweł Horodecki
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Abstract

A crucial question is how objective and classical behavior arises from a fundamental physical theory. Here we provide a natural definition of a decoherence process valid in all causal theories, and show how its behavior can be extremely different from the quantum one. Remarkably, despite this, we prove that the so-called spectrum broadcast structure characterizes all objective states in every fundamental causal theory, exactly as in quantum mechanics. Our results show a stark contrast between the extraordinarily diverse decoherence behavior and the universal features of objectivity.

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Carlo Maria Scandolo, Roberto Salazar, Jarosław K. Korbicz, Paweł Horodecki. 2021-08-13. Universal structure of objective states in all fundamental causal theories. https://doi.org/10.1103/physrevresearch.3.033148

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