General Bounds for Quantum Biased Oracles
-
- Iwama Kazuo
- Graduate School of Informatics, Kyoto University Presently with Imai Quantum Computation and Information Project, ERATO, JST
-
- Raymond Rudy
- Graduate School of Informatics, Kyoto University Presently with Imai Quantum Computation and Information Project, ERATO, JST
-
- Yamashita Shigeru
- Graduate School of Information Science, Nara Institute of Science and Technology
Abstract
An oracle with bias ε is an oracle that answers queries correctly with a probability of at least 1/2+ε. In this paper, we study the upper and lower bounds of quantum query complexity of oracles with bias ε. For general upper bounds, we show that for any quantum algorithm solving some problem with high probability using T queries of perfect quantum oracles, i.e., oracles with ε =1/2, there exists a quantum algorithm solving the same problem, also with high probability, using O(T/ε) queries of the corresponding biased quantum oracles. As corollaries we can show robust quantum algorithms and gaps between biased quantum and classical oracles, e.g., by showing a problem where the quantum query complexity is O(N/ε) but the classical query complexity is lower bounded by Ω(N logN/ε2). For general lower bounds, we generalize Ambainis' quantum adversary argument to biased quantum oracles and obtain the first lower bounds with explicit bias factor. As one of its applications we can provide another proof of the optimality of quantum algorithms for the so-called quantum Goldreich-Levin problem which was proved before by Adcock, et al. using different and more complicated methods.
Journal
-
- IPSJ Digital Courier
-
IPSJ Digital Courier 1 415-425, 2005
Information Processing Society of Japan
- Tweet
Details 詳細情報について
-
- CRID
- 1390282680200837248
-
- NII Article ID
- 130000022370
-
- ISSN
- 13497456
-
- Text Lang
- en
-
- Data Source
-
- JaLC
- Crossref
- CiNii Articles
-
- Abstract License Flag
- Disallowed