dorsal/arxiv
View SchemaWhere was the particle?
| Authors | Sofia Wechsler |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0301098 |
| URL | https://arxiv.org/abs/quant-ph/0301098 |
| License | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
Abstract
The hypothesis of empty/full waves considers that a click in a detector is triggered by a property carried by the wave-packet that impinges on that detector. Different authors call this property particle, but according to the terminology of this hypothesis, the term full wave is used in this text. The present article discusses the validity of the empty/full waves hypothesis. It is shown that the energy conservation principle imposes for a full wave a continuous trajectory from the source to the detector. That gives legitimacy to the question -- in case the wave function consists in a couple of space-separated branches -- which wave-packet was a full wave before the click in the detector, or, in other authors' terminology, where was the particle before the detector clicked. This question is a counterfactual question. In some multi-particle experiments, e.g. Hardy's thought-experiment with an electron and a positron, the combination of the empty/full waves hypothesis and counterfactual reasoning leads to a contradiction with the predictions of the quantum theory. However, it is shown here that this contradiction is solvable if the locality requirement is relaxed. To the difference from the local hidden variables, it is not possible to prove or disprove the idea of empty/ full waves, at least at present. But it is possible to ask whether this hypothesis offers a solution to the quantum puzzles. The answer is negative. For instance it offers no solution to the before-before loop. The question remains open whether the empty/full waves hypothesis is correct, or "God plays dice".
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"abstract": "The hypothesis of empty/full waves considers that a click in a detector is\ntriggered by a property carried by the wave-packet that impinges on that\ndetector. Different authors call this property particle, but according to the\nterminology of this hypothesis, the term full wave is used in this text. The\npresent article discusses the validity of the empty/full waves hypothesis. It\nis shown that the energy conservation principle imposes for a full wave a\ncontinuous trajectory from the source to the detector. That gives legitimacy to\nthe question -- in case the wave function consists in a couple of\nspace-separated branches -- which wave-packet was a full wave before the click\nin the detector, or, in other authors\u0027 terminology, where was the particle\nbefore the detector clicked. This question is a counterfactual question. In\nsome multi-particle experiments, e.g. Hardy\u0027s thought-experiment with an\nelectron and a positron, the combination of the empty/full waves hypothesis and\ncounterfactual reasoning leads to a contradiction with the predictions of the\nquantum theory. However, it is shown here that this contradiction is solvable\nif the locality requirement is relaxed. To the difference from the local hidden\nvariables, it is not possible to prove or disprove the idea of empty/ full\nwaves, at least at present. But it is possible to ask whether this hypothesis\noffers a solution to the quantum puzzles. The answer is negative. For instance\nit offers no solution to the before-before loop. The question remains open\nwhether the empty/full waves hypothesis is correct, or \"God plays dice\".",
"arxiv_id": "quant-ph/0301098",
"authors": [
"Sofia Wechsler"
],
"categories": [
"quant-ph"
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"license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
"title": "Where was the particle?",
"url": "https://arxiv.org/abs/quant-ph/0301098"
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