CTL+ Is Complete for Double Exponential Time

  • Jan Johannsen
  • Martin Lange
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2719)


We show that the satisfiability problem for CTL+, the branching time logic that allows boolean combinations of path formulas inside a path quantifier but no nesting of them, is 2-EXPTIME-hard. The construction is inspired by Vardi and Stockmeyer’s 2-EXPTIME-hardness proof of CTL*’s satisfiability problem. As a consequence, there is no subexponential reduction from CTL+ to CTL which preserves satisfiability.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Jan Johannsen
    • 1
  • Martin Lange
    • 1
  1. 1.Institut für InformatikLudwig-Maximilians-Universität MünchenMunichGermany

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