dorsal/arxiv
View SchemaWelcher Weg Experiments and the Orthodox Bohr's Complementarity Principle
| Authors | S. Bandyopadhyay |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0003073 |
| URL | https://arxiv.org/abs/quant-ph/0003073 |
| DOI | 10.1016/S0375-9601(00)00670-8 |
Abstract
In its most orthodox form, Bohr's Complementarity Principle states that a quanton (a quantum system consisting of a Boson or Fermion) can either behave as a particle or as wave, but never simultaneosuly as both. A less orthodox interpretation of this Principle is the ``duality condition'' embodied in a mathematical inequality due to Englert [B-G Englert, Phys. Rev. Lett., Vol. 77, 2154 (1996)] which allows wave and particle attributes to co-exist, but postulates that a stronger manifestation of the particle nature leads to a weaker manifestation of the wave nature and vice versa. In this Letter, we show that some recent {\it welcher weg} ("which path") experiments in interferometers and similar set-ups, that claim to have validated, or invalidated, the Complementarity Principle, actually shed no light on the orthodox interpretation. They may have instead validated the weaker duality condition, but even that is not completely obvious. We propose simple modifications to these experiments which we believe can test the orthodox Complementarity Principle and also shed light on the nature of wavefunction collapse and quantum erasure.
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"abstract": "In its most orthodox form, Bohr\u0027s Complementarity Principle states that a\nquanton (a quantum system consisting of a Boson or Fermion) can either behave\nas a particle or as wave, but never simultaneosuly as both. A less orthodox\ninterpretation of this Principle is the ``duality condition\u0027\u0027 embodied in a\nmathematical inequality due to Englert [B-G Englert, Phys. Rev. Lett., Vol. 77,\n2154 (1996)] which allows wave and particle attributes to co-exist, but\npostulates that a stronger manifestation of the particle nature leads to a\nweaker manifestation of the wave nature and vice versa. In this Letter, we show\nthat some recent {\\it welcher weg} (\"which path\") experiments in\ninterferometers and similar set-ups, that claim to have validated, or\ninvalidated, the Complementarity Principle, actually shed no light on the\northodox interpretation. They may have instead validated the weaker duality\ncondition, but even that is not completely obvious. We propose simple\nmodifications to these experiments which we believe can test the orthodox\nComplementarity Principle and also shed light on the nature of wavefunction\ncollapse and quantum erasure.",
"arxiv_id": "quant-ph/0003073",
"authors": [
"S. Bandyopadhyay"
],
"categories": [
"quant-ph"
],
"doi": "10.1016/S0375-9601(00)00670-8",
"title": "Welcher Weg Experiments and the Orthodox Bohr\u0027s Complementarity Principle",
"url": "https://arxiv.org/abs/quant-ph/0003073"
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