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Exact results for accepting probabilities of quantum automata

Andris Ambainis·Arnolds Kikusts
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Abstract

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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Andris Ambainis, Arnolds Kikusts. 2002-03-11. Exact results for accepting probabilities of quantum automata. https://arxiv.org/abs/quant-ph/0109136

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