dorsal/arxiv
View SchemaSubstituting a qubit for an arbitrarily large number of classical bits
| Authors | Ernesto F. Galvao, Lucien Hardy |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0110166 |
| URL | https://arxiv.org/abs/quant-ph/0110166 |
| DOI | 10.1103/PhysRevLett.90.087902 |
| Journal | Phys. Rev. Lett. 90, 087902 (2003) |
Abstract
We show that a qubit can be used to substitute for an arbitrarily large number of classical bits. We consider a physical system S interacting locally with a classical field phi(x) as it travels directly from point A to point B. The field has the property that its integrated value is an integer multiple of some constant. The problem is to determine whether the integer is odd or even. This task can be performed perfectly if S is a qubit. On the otherhand, if S is a classical system then we show that it must carry an arbitrarily large amount of classical information. We identify the physical reason for such a huge quantum advantage, and show that it also implies a large difference between the size of quantum and classical memories necessary for some computations. We also present a simple proof that no finite amount of one-way classical communication can perfectly simulate the effect of quantum entanglement.
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"abstract": "We show that a qubit can be used to substitute for an arbitrarily large\nnumber of classical bits. We consider a physical system S interacting locally\nwith a classical field phi(x) as it travels directly from point A to point B.\nThe field has the property that its integrated value is an integer multiple of\nsome constant. The problem is to determine whether the integer is odd or even.\nThis task can be performed perfectly if S is a qubit. On the otherhand, if S is\na classical system then we show that it must carry an arbitrarily large amount\nof classical information. We identify the physical reason for such a huge\nquantum advantage, and show that it also implies a large difference between the\nsize of quantum and classical memories necessary for some computations. We also\npresent a simple proof that no finite amount of one-way classical communication\ncan perfectly simulate the effect of quantum entanglement.",
"arxiv_id": "quant-ph/0110166",
"authors": [
"Ernesto F. Galvao",
"Lucien Hardy"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevLett.90.087902",
"journal_ref": "Phys. Rev. Lett. 90, 087902 (2003)",
"title": "Substituting a qubit for an arbitrarily large number of classical bits",
"url": "https://arxiv.org/abs/quant-ph/0110166"
},
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