On the Computational Complexity of P Automata

  • Erzsébet Csuhaj-Varjú
  • Oscar H. Ibarra
  • György Vaszil
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3384)


We characterize the classes of languages described by P automata, i.e., accepting P systems with communication rules only. Motivated by properties of natural computing systems, we study computational complexity classes with a certain restriction on the use of the available workspace in the course of computations and relate these to the language classes described by P automata. We prove that if the rules of the P system are applied sequentially, then the accepted language class is strictly included in the class of languages accepted by one-way Turing machines with a logarithmically bounded workspace, and if the rules are applied in the maximal parallel manner, then the class of context-sensitive languages is obtained.


Turing Machine Mathematical Linguistics Rule Application Input Symbol Input Tape 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Erzsébet Csuhaj-Varjú
    • 1
  • Oscar H. Ibarra
    • 2
  • György Vaszil
    • 1
  1. 1.Computer and Automation Research InstituteHungarian Academy of SciencesBudapestHungary
  2. 2.Department of Computer ScienceUniversity of CaliforniaSanta BarbaraUSA

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