Kleene Algebra with Converse

  • Paul Brunet
  • Damien Pous
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8428)


The equational theory generated by all algebras of binary relations with operations of union, composition, converse and reflexive transitive closure was studied by Bernátsky, Bloom, Ésik, and Stefanescu in 1995. We reformulate some of their proofs in syntactic and elementary terms, and we provide a new algorithm to decide the corresponding theory. This algorithm is both simpler and more efficient; it relies on an alternative automata construction, that allows us to prove that the considered equational theory lies in the complexity class PSpace.

Specific regular languages appear at various places in the proofs. Those proofs were made tractable by considering appropriate automata recognising those languages, and exploiting symmetries in those automata.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Paul Brunet
    • 1
  • Damien Pous
    • 1
  1. 1.LIP, CNRS, ENS Lyon, INRIAUniversité de LyonUMRFrance

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