dorsal/arxiv
View SchemaImproved quantum algorithms for the ordered search problem via semidefinite programming
| Authors | Andrew M. Childs, Andrew J. Landahl, Pablo A. Parrilo |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0608161 |
| URL | https://arxiv.org/abs/quant-ph/0608161 |
| DOI | 10.1103/PhysRevA.75.032335 |
| Journal | Phys. Rev. A 75, 032335 (2007) |
Abstract
One of the most basic computational problems is the task of finding a desired item in an ordered list of N items. While the best classical algorithm for this problem uses log_2 N queries to the list, a quantum computer can solve the problem using a constant factor fewer queries. However, the precise value of this constant is unknown. By characterizing a class of quantum query algorithms for ordered search in terms of a semidefinite program, we find new quantum algorithms for small instances of the ordered search problem. Extending these algorithms to arbitrarily large instances using recursion, we show that there is an exact quantum ordered search algorithm using 4 log_{605} N \approx 0.433 log_2 N queries, which improves upon the previously best known exact algorithm.
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"abstract": "One of the most basic computational problems is the task of finding a desired\nitem in an ordered list of N items. While the best classical algorithm for this\nproblem uses log_2 N queries to the list, a quantum computer can solve the\nproblem using a constant factor fewer queries. However, the precise value of\nthis constant is unknown. By characterizing a class of quantum query algorithms\nfor ordered search in terms of a semidefinite program, we find new quantum\nalgorithms for small instances of the ordered search problem. Extending these\nalgorithms to arbitrarily large instances using recursion, we show that there\nis an exact quantum ordered search algorithm using 4 log_{605} N \\approx 0.433\nlog_2 N queries, which improves upon the previously best known exact algorithm.",
"arxiv_id": "quant-ph/0608161",
"authors": [
"Andrew M. Childs",
"Andrew J. Landahl",
"Pablo A. Parrilo"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.75.032335",
"journal_ref": "Phys. Rev. A 75, 032335 (2007)",
"title": "Improved quantum algorithms for the ordered search problem via semidefinite programming",
"url": "https://arxiv.org/abs/quant-ph/0608161"
},
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