Quantum Nonlocality in Networks Can Be Demonstrated with an Arbitrarily Small Level of Independence between the Sources

Ivan Šupić, Jean-Daniel Bancal, and Nicolas Brunner
Phys. Rev. Lett. 125, 240403 – Published 9 December 2020
PDFHTMLExport Citation

Abstract

Quantum nonlocality can be observed in networks even in the case where every party can only perform a single measurement, i.e., does not receive any input. So far, this effect has been demonstrated under the assumption that all sources in the network are fully independent from each other. Here we investigate to what extent this independence assumption can be relaxed. After formalizing the question, we show that, in the triangle network without inputs, quantum nonlocality can be observed, even when assuming only an arbitrarily small level of independence between the sources. This means that quantum predictions cannot be reproduced by a local model unless the three sources can be perfectly correlated.

  • Figure
  • Received 31 August 2020
  • Accepted 3 November 2020

DOI:https://doi.org/10.1103/PhysRevLett.125.240403

© 2020 American Physical Society

Physics Subject Headings (PhySH)

Quantum Information, Science & TechnologyGeneral Physics

Authors & Affiliations

Ivan Šupić*, Jean-Daniel Bancal, and Nicolas Brunner

  • Département de Physique Appliquée, Université de Genève, 1211 Genève, Switzerland

  • *ivan.supic@unige.ch

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 125, Iss. 24 — 11 December 2020

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×