dorsal/arxiv
View SchemaAn anomaly of non-locality
| Authors | A. A. Methot, V. Scarani |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0601210 |
| URL | https://arxiv.org/abs/quant-ph/0601210 |
| Journal | Quantum Information and Computation 7: 157-170, 2007. |
Abstract
Ever since the work of Bell, it has been known that entangled quantum states can rise non-local correlations. However, for almost forty years, it has been assumed that the most non-local states would be the maximally entangled ones. Surprisingly it is not the case: non-maximally entangled states are generally more non-local than maximally entangled states for all the measures of non-locality proposed to date: Bell inequalities, the Kullback-Leibler distance, entanglement simulation with communication or with non-local boxes, the detection loophole and efficiency of cryptography. In fact, one can even find simple examples in low dimensions, confirming that it is not an artefact of a specifically constructed Hilbert space or topology. This anomaly shows that entanglement and non-locality are not only different concepts, but also truly different resources. We review the present knowledge on this anomaly, point out that Hardy's theorem has the same feature, and discuss the perspectives opened by these discoveries.
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"abstract": "Ever since the work of Bell, it has been known that entangled quantum states\ncan rise non-local correlations. However, for almost forty years, it has been\nassumed that the most non-local states would be the maximally entangled ones.\nSurprisingly it is not the case: non-maximally entangled states are generally\nmore non-local than maximally entangled states for all the measures of\nnon-locality proposed to date: Bell inequalities, the Kullback-Leibler\ndistance, entanglement simulation with communication or with non-local boxes,\nthe detection loophole and efficiency of cryptography. In fact, one can even\nfind simple examples in low dimensions, confirming that it is not an artefact\nof a specifically constructed Hilbert space or topology. This anomaly shows\nthat entanglement and non-locality are not only different concepts, but also\ntruly different resources. We review the present knowledge on this anomaly,\npoint out that Hardy\u0027s theorem has the same feature, and discuss the\nperspectives opened by these discoveries.",
"arxiv_id": "quant-ph/0601210",
"authors": [
"A. A. Methot",
"V. Scarani"
],
"categories": [
"quant-ph"
],
"journal_ref": "Quantum Information and Computation 7: 157-170, 2007.",
"title": "An anomaly of non-locality",
"url": "https://arxiv.org/abs/quant-ph/0601210"
},
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