Decidability of bisimulation equivalence for processes generating context-free languages

  • J. C. M. Baeten
  • J. A. Bergstra
  • J. W. Klop
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 259)


A context-free grammar (CFG) in Greibach Normal Form coincides, in another notation, with a system of guarded recursion equations in Basic Process Algebra. Hence to each CFG a process can be assigned as solution, which has as its set of finite traces the context-free language (CFL) determined by that CFG. While the equality problem for CFL's is unsolvable, the equality problem for the processes determined by CFG's turns out to be solvable. Here equality on processes is given by a model of process graphs modulo bisimulation equivalence. The proof is given by displaying a periodic structure of the process graphs determined by CFG's. As a corollary of the periodicity a short proof of the solvability of the equivalence problem for simple context-free languages is given.


Equality Problem Recursion Equation Process Algebra Communicate Sequential Process Trace Semantic 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • J. C. M. Baeten
    • 1
  • J. A. Bergstra
    • 1
    • 2
  • J. W. Klop
    • 3
  1. 1.Computer Science DepartmentUniversity of AmsterdamThe Netherlands
  2. 2.Department of PhilosophyState University of UtrechtThe Netherlands
  3. 3.Centre for Mathematics and Computer ScienceAmsterdam

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