dorsal/arxiv
View SchemaIn defense of the epistemic view of quantum states: a toy theory
| Authors | Robert W. Spekkens |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0401052 |
| URL | https://arxiv.org/abs/quant-ph/0401052 |
| DOI | 10.1103/PhysRevA.75.032110 |
| Journal | Phys. Rev. A 75, 032110 (2007) |
Abstract
We present a toy theory that is based on a simple principle: the number of questions about the physical state of a system that are answered must always be equal to the number that are unanswered in a state of maximal knowledge. A wide variety of quantum phenomena are found to have analogues within this toy theory. Such phenomena include: the noncommutativity of measurements, interference, the multiplicity of convex decompositions of a mixed state, the impossibility of discriminating nonorthogonal states, the impossibility of a universal state inverter, the distinction between bi-partite and tri-partite entanglement, the monogamy of pure entanglement, no cloning, no broadcasting, remote steering, teleportation, dense coding, mutually unbiased bases, and many others. The diversity and quality of these analogies is taken as evidence for the view that quantum states are states of incomplete knowledge rather than states of reality. A consideration of the phenomena that the toy theory fails to reproduce, notably, violations of Bell inequalities and the existence of a Kochen-Specker theorem, provides clues for how to proceed with this research program.
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"abstract": "We present a toy theory that is based on a simple principle: the number of\nquestions about the physical state of a system that are answered must always be\nequal to the number that are unanswered in a state of maximal knowledge. A wide\nvariety of quantum phenomena are found to have analogues within this toy\ntheory. Such phenomena include: the noncommutativity of measurements,\ninterference, the multiplicity of convex decompositions of a mixed state, the\nimpossibility of discriminating nonorthogonal states, the impossibility of a\nuniversal state inverter, the distinction between bi-partite and tri-partite\nentanglement, the monogamy of pure entanglement, no cloning, no broadcasting,\nremote steering, teleportation, dense coding, mutually unbiased bases, and many\nothers. The diversity and quality of these analogies is taken as evidence for\nthe view that quantum states are states of incomplete knowledge rather than\nstates of reality. A consideration of the phenomena that the toy theory fails\nto reproduce, notably, violations of Bell inequalities and the existence of a\nKochen-Specker theorem, provides clues for how to proceed with this research\nprogram.",
"arxiv_id": "quant-ph/0401052",
"authors": [
"Robert W. Spekkens"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.75.032110",
"journal_ref": "Phys. Rev. A 75, 032110 (2007)",
"title": "In defense of the epistemic view of quantum states: a toy theory",
"url": "https://arxiv.org/abs/quant-ph/0401052"
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