On the Class of Languages Recognizable by 1-Way Quantum Finite Automata

  • Andris Ambainis1
  • Arnolds KĶikusts
  • Māris Valdats
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2010)


It is an open problem to characterize the class of languages recognized by quantum finite automata (QFA). We examine some neces- sary and some sufficient conditions for a (regular) language to be recog- nizable by a QFA. For a subclass of regular languages we get a condition which is necessary and sufficient.

Also, we prove that the class of languages recognizable by a QFA is not closed under union or any other binary Boolean operation where both arguments are significant.


Regular Language Classi Cation Probabilistic Automaton Minimal Automaton Recognizable Language 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Andris Ambainis1
    • 1
  • Arnolds KĶikusts
    • 2
  • Māris Valdats
    • 2
  1. 1.Computer Science DivisionUniversity of CaliforniaBerkeleyUSA
  2. 2.Institute of Mathematics and Computer ScienceUniversity of LatviaRīgaLatvia

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