The Expressive Power of Two-Variable Least Fixed-Point Logics

  • Martin Grohe
  • Stephan Kreutzer
  • Nicole Schweikardt
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3618)


The present paper gives a classification of the expressive power of two-variable least fixed-point logics. The main results are:

  1. 1

    The two-variable fragment of monadic least fixed-point logic with parameters is as expressive as full monadic least fixed-point logic (on binary structures).

  2. 2

    The two-variable fragment of monadic least fixed-point logic without parameters is as expressive as the two-variable fragment of binary least fixed-point logic without parameters.

  3. 3

    The two-variable fragment of binary least fixed-point logic with parameters is strictly more expressive than the two-variable fragment of monadic least fixed-point logic with parameters (even on finite strings).



Modal Logic Monotone Operator Expressive Power Binary Signature Model Check Problem 
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 2005

Authors and Affiliations

  • Martin Grohe
    • 1
  • Stephan Kreutzer
    • 1
  • Nicole Schweikardt
    • 1
  1. 1.Institut für InformatikHumboldt-UniversitätBerlin

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