dorsal/arxiv
View SchemaNo-relationship between impossibility of faster-than-light quantum communication and distinction of ensembles with the same density matrix
| Authors | Chuan Wang, Gui Lu Long, Yang Sun |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0506047 |
| URL | https://arxiv.org/abs/quant-ph/0506047 |
| DOI | 10.1088/6102/44/4/622 |
| Journal | Commun. Theor. Phys. (Beijing, China) 44 (2005) pp. 622-624 |
Abstract
It has been claimed in the literature that impossibility of faster-than-light quantum communication has an origin of indistinguishability of ensembles with the same density matrix. We show that the two concepts are not related. We argue that: 1) even with an ideal single-atom-precision measurement, it is generally impossible to produce two ensembles with exactly the same density matrix; or 2) to produce ensembles with the same density matrix, classical communication is necessary. Hence the impossibility of faster-than-light communication does not imply the indistinguishability of ensembles with the same density matrix.
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"abstract": "It has been claimed in the literature that impossibility of faster-than-light\nquantum communication has an origin of indistinguishability of ensembles with\nthe same density matrix. We show that the two concepts are not related. We\nargue that: 1) even with an ideal single-atom-precision measurement, it is\ngenerally impossible to produce two ensembles with exactly the same density\nmatrix; or 2) to produce ensembles with the same density matrix, classical\ncommunication is necessary. Hence the impossibility of faster-than-light\ncommunication does not imply the indistinguishability of ensembles with the\nsame density matrix.",
"arxiv_id": "quant-ph/0506047",
"authors": [
"Chuan Wang",
"Gui Lu Long",
"Yang Sun"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/6102/44/4/622",
"journal_ref": "Commun. Theor. Phys. (Beijing, China) 44 (2005) pp. 622-624",
"title": "No-relationship between impossibility of faster-than-light quantum communication and distinction of ensembles with the same density matrix",
"url": "https://arxiv.org/abs/quant-ph/0506047"
},
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