The NP-Completeness of Reflected Fragments of Justification Logics

  • Samuel R. Buss
  • Roman Kuznets
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5407)


Justification Logic studies epistemic and provability phenomena by introducing justifications/proofs into the language in the form of justification terms. Pure justification logics serve as counterparts of traditional modal epistemic logics, and hybrid logics combine epistemic modalities with justification terms. The computational complexity of pure justification logics is typically lower than that of the corresponding modal logics. Moreover, the so-called reflected fragments, which still contain complete information about the respective justification logics, are known to be in NP for a wide range of justification logics, pure and hybrid alike. This paper shows that, under reasonable additional restrictions, these reflected fragments are NP-complete, thereby proving a matching lower bound.


Modal Logic Vertex Cover Epistemic Modality Axiom Scheme Hybrid Logic 
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 2008

Authors and Affiliations

  • Samuel R. Buss
    • 1
  • Roman Kuznets
    • 2
  1. 1.Department of MathematicsUniversity of CaliforniaSan DiegoUSA
  2. 2.Institut für Informatik und angewandte MathematikUniversität BernBernSwitzerland

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