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The word matching problem is undecidable for finite special string-rewriting systems that are confluent

  • Paliath Narendran
  • Friedrich Otto
Session 16: Rewriting
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1256)

Abstract

We present a finite, special, and confluent string-rewriting system for which the word matching problem is undecidable. Since the word matching problem is the non-symmetric restriction of the word unification problem, this presents a non-trivial improvement of the recent result that for this type of string-rewriting systems, the word unification problem is undecidable (Otto 1995). In fact, we show that our undecidability result remains valid even when we only consider very restricted instances of the word matching problem.

Keywords

matching unification equational theory string-rewriting systems 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Paliath Narendran
    • 1
  • Friedrich Otto
    • 2
  1. 1.Institute of Programming and Logics, Department of Computer ScienceState University of New York at AlbanyAlbanyUSA
  2. 2.Fachbereich Mathematik/InformatikUniversität KasselKasselGermany

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