English

Limitations on separable measurements by convex optimization

Quantum Physics 2021-01-05 v2

Abstract

We prove limitations on LOCC and separable measurements in bipartite state discrimination problems using techniques from convex optimization. Specific results that we prove include: an exact formula for the optimal probability of correctly discriminating any set of either three or four Bell states via LOCC or separable measurements when the parties are given an ancillary partially entangled pair of qubits; an easily checkable characterization of when an unextendable product set is perfectly discriminated by separable measurements, along with the first known example of an unextendable product set that cannot be perfectly discriminated by separable measurements; and an optimal bound on the success probability for any LOCC or separable measurement for the recently proposed state discrimination problem of Yu, Duan, and Ying.

Keywords

Cite

@article{arxiv.1408.6981,
  title  = {Limitations on separable measurements by convex optimization},
  author = {Somshubhro Bandyopadhyay and Alessandro Cosentino and Nathaniel Johnston and Vincent Russo and John Watrous and Nengkun Yu},
  journal= {arXiv preprint arXiv:1408.6981},
  year   = {2021}
}

Comments

22 pages, v2 includes minor corrections

R2 v1 2026-06-22T05:43:54.259Z