An Efficient Simulation of Polynomial-Space Turing Machines by P Systems with Active Membranes

نویسندگان

  • Andrea Valsecchi
  • Antonio E. Porreca
  • Alberto Leporati
  • Giancarlo Mauri
  • Claudio Zandron
چکیده

We show that a deterministic single-tape Turing machine, operating in polynomial space with respect to the input length, can be efficiently simulated (both in terms of time and space) by a semi-uniform family of P systems with active membranes and three polarizations, using only communication rules. Then, basing upon this simulation, we prove that a result similar to the space hierarchy theorem can be obtained for P systems with active membranes: the larger the amount of space we can use during the computations, the harder the problems we are able to solve.

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تاریخ انتشار 2009