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Stronger Quantum Correlations with Loophole-free Post-selection

Quantum Physics 2011-09-16 v4

Abstract

One of the most striking non-classical features of quantum mechanics is in the correlations it predicts between spatially separated measurements. In local hidden variable theories, correlations are constrained by Bell inequalities, but quantum correlations violate these. However, experimental imperfections lead to "loopholes" whereby LHV correlations are no longer constrained by Bell inequalities, and violations can be described by LHV theories. For example, loopholes can emerge through selective detection of events. In this letter, we introduce a clean, operational picture of multi-party Bell tests, and show that there exists a non-trivial form of loophole-free post-selection. Surprisingly, the same post-selection can enhance quantum correlations, and unlock a connection between non-classical correlations and non-classical computation.

Keywords

Cite

@article{arxiv.1102.1438,
  title  = {Stronger Quantum Correlations with Loophole-free Post-selection},
  author = {Matty J. Hoban and Dan E. Browne},
  journal= {arXiv preprint arXiv:1102.1438},
  year   = {2011}
}

Comments

4 pages, 2 figures, substantially revised in response to referee suggestions

R2 v1 2026-06-21T17:22:57.341Z