1-way quantum finite automata: strengths, weaknesses and generalizations

  title={1-way quantum finite automata: strengths, weaknesses and generalizations},
  author={Andris Ambainis and Rusins Freivalds},
  journal={Proceedings 39th Annual Symposium on Foundations of Computer Science (Cat. No.98CB36280)},
  • A. AmbainisR. Freivalds
  • Published 24 February 1998
  • Computer Science
  • Proceedings 39th Annual Symposium on Foundations of Computer Science (Cat. No.98CB36280)
We study 1-way quantum finite automata (QFAs). First, we compare them with their classical counterparts. We show that, if an automaton is required to give the correct answer with a large probability (greater than 7/9), then any 1-way QFAs can be simulated by a 1-way reversible automaton. However, quantum automata giving the correct answer with smaller probabilities are more powerful than reversible automata. Second, we show that 1-way QFAs can be very space-efficient. We construct a 1-way QFA… 

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