English

Limits on correlations in networks for quantum and no-signaling resources

Quantum Physics 2019-08-21 v1

Abstract

A quantum network consists of independent sources distributing entangled states to distant nodes which can then perform entangled measurements, thus establishing correlations across the entire network. But how strong can these correlations be? Here we address this question, by deriving bounds on possible quantum correlations in a given network. These bounds are nonlinear inequalities that depend only on the topology of the network. We discuss in detail the notably challenging case of the triangle network. Moreover, we conjecture that our bounds hold in general no-signaling theories. In particular, we prove that our inequalities for the triangle network hold when the sources are arbitrary no-signaling boxes which can be wired together. Finally, we discuss an application of our results for the device-independent characterization of the topology of a quantum network.

Keywords

Cite

@article{arxiv.1901.08287,
  title  = {Limits on correlations in networks for quantum and no-signaling resources},
  author = {Marc-Olivier Renou and Yuyi Wang and Sadra Boreiri and Salman Beigi and Nicolas Gisin and Nicolas Brunner},
  journal= {arXiv preprint arXiv:1901.08287},
  year   = {2019}
}

Comments

15 pages, 6 figures