A survey on space complexity of P systems with active membranes

P systems with active membranes are a variant of P systems where membranes play an active role during the computation, for example by dividing existing membranes in order to create new ones. In this way, an exponential number of membranes can be obtained in polynomial time, and then used in parallel to attack computationally hard problems. Many interesting questions arise concerning the trade-off between time and space needed to solve various classes of computational problems by means of such membrane systems. In this paper we overview the main results presented in the literature concerning this subject.