1999/11/30 by Barbara M. Terhal · 19 citations
Computer Science · Mathematics · Physics and Astronomy · #Bell state #Bell test experiments #Bell's theorem #Bipartite graph #CHSH inequality #Computer science #Discrete mathematics #Graph #Hidden variable theory #Inequality #Local hidden variable theory #Mathematical analysis #Mathematics #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #Set (abstract data type) #Statistical physics #Variable (mathematics) #Witness #quant-ph
paper · pdf · doi:10.1016/s0375-9601(00)00401-1
published as Physics Letters A Vol. 271, 319 (2000) · 16 pages Revtex, typo in equation (14) corrected
openalex publication_date 2000/07/01 · arxiv created 2000/11/27 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We analyze and compare the mathematical formulations of the criterion for separability for bipartite density matrices and the Bell inequalities. We show that a violation of a Bell inequality can formally be expressed as a witness for entanglement. We also show how the criterion for separability and a description of the state by a local hidden variable theory, become equivalent when we restrict the set of local hidden variable theories to the domain of quantum mechanics. This analysis sheds light on the essential difference between the two criteria and may help us in understanding whether there exist entangled states for which the statistics of the outcomes of all possible local measurements can be described by a local hidden variable theory.