dorsal/arxiv
View SchemaQuantum nonlocality and inseparability
| Authors | Asher Peres |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9609016 |
| URL | https://arxiv.org/abs/quant-ph/9609016 |
| Journal | "New Developments on Fundamental Problems in Quantum Physics" ed. by M. Ferrero and A. van der Merwe (Kluwer, 1997) pp.301-310 |
Abstract
A quantum system consisting of two subsystems is separable if its density matrix can be written as $\rho=\sum w_K \rho_K'\otimes \rho_K''$, where $\rho_K'$ and $\rho_K''$ are density matrices for the two subsytems, and the positive weights $w_K$ satisfy $\sum w_K=1$. A necessary condition for separability is derived and is shown to be more sensitive than Bell's inequality for detecting quantum inseparability. Moreover, collective tests of Bell's inequality (namely, tests that involve several composite systems simultaneously) may sometimes lead to a violation of Bell's inequality, even if the latter is satisfied when each composite system is tested separately.
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"abstract": "A quantum system consisting of two subsystems is separable if its density\nmatrix can be written as $\\rho=\\sum w_K \\rho_K\u0027\\otimes \\rho_K\u0027\u0027$, where\n$\\rho_K\u0027$ and $\\rho_K\u0027\u0027$ are density matrices for the two subsytems, and the\npositive weights $w_K$ satisfy $\\sum w_K=1$. A necessary condition for\nseparability is derived and is shown to be more sensitive than Bell\u0027s\ninequality for detecting quantum inseparability. Moreover, collective tests of\nBell\u0027s inequality (namely, tests that involve several composite systems\nsimultaneously) may sometimes lead to a violation of Bell\u0027s inequality, even if\nthe latter is satisfied when each composite system is tested separately.",
"arxiv_id": "quant-ph/9609016",
"authors": [
"Asher Peres"
],
"categories": [
"quant-ph"
],
"journal_ref": "\"New Developments on Fundamental Problems in Quantum Physics\" ed.\n by M. Ferrero and A. van der Merwe (Kluwer, 1997) pp.301-310",
"title": "Quantum nonlocality and inseparability",
"url": "https://arxiv.org/abs/quant-ph/9609016"
},
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