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arXiv quant-ph/01091362001-09quant-ph

Exact results for accepting probabilities of quantum automata

Andris Ambainis, Arnolds Kikusts

备注：: 26 pages, 4 figures, submitted to Theoretical Computer Science (earlier version at STACS'01)
发表信息：: Theoretical Computer Science, 295(2003):3-25

英文摘要：

One of the properties of Kondacs-Watrous model of quantum finite automata (QFA) is that the probability of the correct answer for a QFA cannot be amplified arbitrarily. In this paper, we determine the maximum probabilities achieved by QFAs for several languages. In particular, we show that any language that is not recognized by an RFA (reversible finite automaton) can be recognized by a QFA with probability at most 0.7726...

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