dorsal/arxiv
View SchemaRelativistic Doppler effect in quantum communication
| Authors | Asher Peres, Daniel R. Terno |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0208128 |
| URL | https://arxiv.org/abs/quant-ph/0208128 |
| DOI | 10.1080/09500340308234560 |
| Journal | J. Mod. Opt. 50, 1165 (2003) |
Abstract
When an electromagnetic signal propagates in vacuo, a polarization detector cannot be rigorously perpendicular to the wave vector because of diffraction effects. The vacuum behaves as a noisy channel, even if the detectors are perfect. The ``noise'' can however be reduced and nearly cancelled by a relative motion of the observer toward the source. The standard definition of a reduced density matrix fails for photon polarization, because the transversality condition behaves like a superselection rule. We can however define an effective reduced density matrix which corresponds to a restricted class of positive operator-valued measures. There are no pure photon qubits, and no exactly orthogonal qubit states.
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"abstract": "When an electromagnetic signal propagates in vacuo, a polarization detector\ncannot be rigorously perpendicular to the wave vector because of diffraction\neffects. The vacuum behaves as a noisy channel, even if the detectors are\nperfect. The ``noise\u0027\u0027 can however be reduced and nearly cancelled by a\nrelative motion of the observer toward the source. The standard definition of a\nreduced density matrix fails for photon polarization, because the\ntransversality condition behaves like a superselection rule. We can however\ndefine an effective reduced density matrix which corresponds to a restricted\nclass of positive operator-valued measures. There are no pure photon qubits,\nand no exactly orthogonal qubit states.",
"arxiv_id": "quant-ph/0208128",
"authors": [
"Asher Peres",
"Daniel R. Terno"
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"quant-ph"
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"doi": "10.1080/09500340308234560",
"journal_ref": "J. Mod. Opt. 50, 1165 (2003)",
"title": "Relativistic Doppler effect in quantum communication",
"url": "https://arxiv.org/abs/quant-ph/0208128"
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