dorsal/arxiv
View SchemaCausal Quantum Theory and the Collapse Locality Loophole
| Authors | Adrian Kent |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0204104 |
| URL | https://arxiv.org/abs/quant-ph/0204104 |
| DOI | 10.1103/PhysRevA.72.012107 |
| Journal | Phys. Rev. A 72, 012107 (2005) |
Abstract
Causal quantum theory is an umbrella term for ordinary quantum theory modified by two hypotheses: state vector reduction is a well-defined process, and strict local causality applies. The first of these holds in some versions of Copenhagen quantum theory and need not necessarily imply practically testable deviations from ordinary quantum theory. The second implies that measurement events which are spacelike separated have no non-local correlations. To test this prediction, which sharply differs from standard quantum theory, requires a precise theory of state vector reduction. Formally speaking, any precise version of causal quantum theory defines a local hidden variable theory. However, causal quantum theory is most naturally seen as a variant of standard quantum theory. For that reason it seems a more serious rival to standard quantum theory than local hidden variable models relying on the locality or detector efficiency loopholes. Some plausible versions of causal quantum theory are not refuted by any Bell experiments to date, nor is it obvious that they are inconsistent with other experiments. They evade refutation via a neglected loophole in Bell experiments -- the {\it collapse locality loophole} -- which exists because of the possible time lag between a particle entering a measuring device and a collapse taking place. Fairly definitive tests of causal versus standard quantum theory could be made by observing entangled particles separated by $\approx 0.1$ light seconds.
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"abstract": "Causal quantum theory is an umbrella term for ordinary quantum theory\nmodified by two hypotheses: state vector reduction is a well-defined process,\nand strict local causality applies. The first of these holds in some versions\nof Copenhagen quantum theory and need not necessarily imply practically\ntestable deviations from ordinary quantum theory. The second implies that\nmeasurement events which are spacelike separated have no non-local\ncorrelations. To test this prediction, which sharply differs from standard\nquantum theory, requires a precise theory of state vector reduction.\n Formally speaking, any precise version of causal quantum theory defines a\nlocal hidden variable theory. However, causal quantum theory is most naturally\nseen as a variant of standard quantum theory. For that reason it seems a more\nserious rival to standard quantum theory than local hidden variable models\nrelying on the locality or detector efficiency loopholes.\n Some plausible versions of causal quantum theory are not refuted by any Bell\nexperiments to date, nor is it obvious that they are inconsistent with other\nexperiments. They evade refutation via a neglected loophole in Bell experiments\n-- the {\\it collapse locality loophole} -- which exists because of the possible\ntime lag between a particle entering a measuring device and a collapse taking\nplace. Fairly definitive tests of causal versus standard quantum theory could\nbe made by observing entangled particles separated by $\\approx 0.1$ light\nseconds.",
"arxiv_id": "quant-ph/0204104",
"authors": [
"Adrian Kent"
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"doi": "10.1103/PhysRevA.72.012107",
"journal_ref": "Phys. Rev. A 72, 012107 (2005)",
"title": "Causal Quantum Theory and the Collapse Locality Loophole",
"url": "https://arxiv.org/abs/quant-ph/0204104"
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