Scientific article
Open access

Constraints on nonlocality in networks from no-signaling and independence

Published inNature Communications, vol. 11, no. 1, p. 1-6
Publication date2020

The possibility of Bell inequality violations in quantum theory had a profound impact on our understanding of the correlations that can be shared by distant parties. Generalizing the concept of Bell nonlocality to networks leads to novel forms of correlations, the characterization of which is, however, challenging. Here, we investigate constraints on correlations in networks under the natural assumptions of no-signaling and independence of the sources. We consider the triangle network with binary outputs, and derive strong constraints on correlations even though the parties receive no input, i.e., each party performs a fixed measurement. We show that some of these constraints are tight, by constructing explicit local models (i.e. where sources distribute classical variables) that can saturate them. However, we also observe that other constraints can apparently not be saturated by local models, which opens the possibility of having nonlocal (but non-signaling) correlations in the triangle network with binary outputs.

Research group
  • Swiss National Science Foundation - Starting grant DIAQ, NCCR-QSIT, and NCCR-Swissmap
Citation (ISO format)
GISIN, Nicolas et al. Constraints on nonlocality in networks from no-signaling and independence. In: Nature Communications, 2020, vol. 11, n° 1, p. 1–6. doi: 10.1038/s41467-020-16137-4
Main files (2)
Article (Accepted version)
Article (Published version)
ISSN of the journal2041-1723

Technical informations

Creation07/01/2020 8:38:00 PM
First validation07/01/2020 8:38:00 PM
Update time03/15/2023 10:13:56 PM
Status update03/15/2023 10:13:55 PM
Last indexation02/12/2024 11:52:39 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack