dorsal/arxiv
View SchemaNoncommuting Observables and Local Realism
| Authors | James D. Malley, Arthur Fine |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0505016 |
| URL | https://arxiv.org/abs/quant-ph/0505016 |
Abstract
A standard approach in the foundations of quantum mechanics studies local realism and hidden variables models exclusively in terms of violations of Bell-like inequalities. Thus quantum nonlocality is tied to the celebrated no-go theorems, and these comprise a long list that includes the Kochen-Specker and Bell theorems, as well as elegant refinements by Mermin, Peres, Hardy, GHZ, and many others. Typically entanglement or carefully prepared multipartite systems have been considered essential for violations of local realism and for understanding quantum nonlocality. Here we show, to the contrary, that sharp violations of local realism arise almost everywhere without entanglement. The pivotal fact driving these violations is just the noncommutativity of quantum observables. We demonstrate how violations of local realism occur for arbitrary noncommuting projectors, and for arbitrary quantum pure states. Finally, we point to elementary tests for local realism, using single particles and without reference to entanglement, thus avoiding experimental loopholes and efficiency issues that continue to bedevil the Bell inequality related tests.
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"abstract": "A standard approach in the foundations of quantum mechanics studies local\nrealism and hidden variables models exclusively in terms of violations of\nBell-like inequalities. Thus quantum nonlocality is tied to the celebrated\nno-go theorems, and these comprise a long list that includes the Kochen-Specker\nand Bell theorems, as well as elegant refinements by Mermin, Peres, Hardy, GHZ,\nand many others. Typically entanglement or carefully prepared multipartite\nsystems have been considered essential for violations of local realism and for\nunderstanding quantum nonlocality. Here we show, to the contrary, that sharp\nviolations of local realism arise almost everywhere without entanglement. The\npivotal fact driving these violations is just the noncommutativity of quantum\nobservables. We demonstrate how violations of local realism occur for arbitrary\nnoncommuting projectors, and for arbitrary quantum pure states. Finally, we\npoint to elementary tests for local realism, using single particles and without\nreference to entanglement, thus avoiding experimental loopholes and efficiency\nissues that continue to bedevil the Bell inequality related tests.",
"arxiv_id": "quant-ph/0505016",
"authors": [
"James D. Malley",
"Arthur Fine"
],
"categories": [
"quant-ph"
],
"title": "Noncommuting Observables and Local Realism",
"url": "https://arxiv.org/abs/quant-ph/0505016"
},
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