Observers of quantum systems cannot agree to disagree.
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ABSTRACT:
SUBMITTER: Contreras-Tejada P
PROVIDER: S-EPMC8640027 | biostudies-literature | 2021 Dec
REPOSITORIES: biostudies-literature
Publications
Observers of quantum systems cannot agree to disagree.
Contreras-Tejada Patricia P Scarpa Giannicola G Kubicki Aleksander M AM Brandenburger Adam A La Mura Pierfrancesco P
Nature communications 20211202 1
Is the world quantum? An active research line in quantum foundations is devoted to exploring what constraints can rule out the postquantum theories that are consistent with experimentally observed results. We explore this question in the context of epistemics, and ask whether agreement between observers can serve as a physical principle that must hold for any theory of the world. Aumann's seminal Agreement Theorem states that two observers (of classical systems) cannot agree to disagree. We prop ...[more]
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