In [NO88], a particular trace monoid M is constructed such that for the class of length-reducing trace rewriting systems over M, confluence is undecidable. In this paper, we show that this result holds for every trace monoid, which is neither free nor free commutative. Furthermore we will present a new criterion for trace rewriting systems that implies decidability of confluence.


Turing Machine Critical Pair Free Monoid Trace Theory Clique Covering 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Markus Lohrey
    • 1
  1. 1.Institut für InformatikUniversität StuttgartStuttgart

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