Post Correspondence Problem: Primitivity and interrelations with complexity classes

  • Alexandru Mateescu
  • Arto Salomaa
Invited Lectures
Part of the Lecture Notes in Computer Science book series (LNCS, volume 711)


We first introduce the notion of a general primality type, for a systematic study of “simple”, “primitive” or “prime” solutions of the Post Correspondence Problem. We give an exhaustive charcterization of general primality types. We then introduce PCP-related complexity classes, for instance, the time complexity classes PCP-P and PCP-NP. We obtain the chain of inclusions
$$P \subseteqq PCP - P \subseteqq PCP - NP = NP \subseteqq P - SPACE = PCP - P - SPACE = PCP - NP - SPACE.$$


Target Word Space Complexity Complexity Class Primality Type Fundamental Lemma 
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 1993

Authors and Affiliations

  • Alexandru Mateescu
    • 1
  • Arto Salomaa
    • 2
  1. 1.Faculty of MathematicsUniversity of BucharestBucharestRomania
  2. 2.Academy of Finland and Mathematics DepartmentUniversity of TurkuTurkuFinland

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