Undecidable properties of flat term rewrite systems

  • Guillem Godoy
  • Hugo Hernández


Reachability, joinability and confluence properties are known to be undecidable for flat term rewrite systems (TRS). We give shorter and conceptually simpler proofs of these results. We also prove undecidability of weak normalization and unique normalization properties for flat TRS.


Term rewriting Syntactic restrictions Undecidability 

Mathematics Subject Classification (2000)

16S15 68Q42 


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Universitat Politèctina de CatalunyaBarcelonaSpain

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