dorsal/arxiv
View SchemaMeaning of the Density Matrix
| Authors | Y. Aharonov, J. Anandan |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9803018 |
| URL | https://arxiv.org/abs/quant-ph/9803018 |
Abstract
Protective measurement, which was proposed as a method of observing the wavefunction of a single system, is extended to the observation of the density matrix of a single system. d'Espagnat's definition of `proper mixture' is shown to be improper because it does not allow for appropriate fluctuations. His claim that there could be different mixtures corresponding to the same density matrix is critically examined. These results provide a new meaning to the density matrix, which gives it the same ontological status as the wavefunction describing a pure state. This also enables quantum entropy to be associated with a single system.
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"abstract": "Protective measurement, which was proposed as a method of observing the\nwavefunction of a single system, is extended to the observation of the density\nmatrix of a single system. d\u0027Espagnat\u0027s definition of `proper mixture\u0027 is shown\nto be improper because it does not allow for appropriate fluctuations. His\nclaim that there could be different mixtures corresponding to the same density\nmatrix is critically examined. These results provide a new meaning to the\ndensity matrix, which gives it the same ontological status as the wavefunction\ndescribing a pure state. This also enables quantum entropy to be associated\nwith a single system.",
"arxiv_id": "quant-ph/9803018",
"authors": [
"Y. Aharonov",
"J. Anandan"
],
"categories": [
"quant-ph"
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"title": "Meaning of the Density Matrix",
"url": "https://arxiv.org/abs/quant-ph/9803018"
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