Solving NP-complete Problems in Polynomial Time by Using a Natural Computing Model

  • Bogdan AmanEmail author
  • Gabriel Ciobanu
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 594)


The first part of the paper is devoted to a polynomial solution of a well-known NP-complete problem (SAT problem) by using an unconventional computation model provided by P systems with active membranes (with neither polarization nor division rules). An important step of this semi-uniform solution is given by polynomial computing devices to build P systems that contain some exponential-size feature for which solving the SAT problem is easy. NP-complete problems are decision problems that can be solved in polynomial time on a non-deterministic Turing machine. Related to this step, in the second part we show how we can simulate polynomial space Turing machines by using a logarithmic space P system with active membranes, and employing a binary representation in order to encode the positions on the Turing machine tape.


Natural computing Membrane computing Turing machines 


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Romanian Academy, Institute of Computer ScienceIaşiRomania

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