On Promoters/Inhibitors and Symport/Antiport with Traces in P Systems

Resumen

This article brings together some rather powerful results on P systems in which the computation is performed by the communication of objects through symport and antiport rules considering the trace of an object through membranes, on the one hand, and by P systems with object-rewriting non-cooperative rules, promoters/inhibitors at the level of rules and only one catalyst, on the other. It is recalled here that computational universality can be reached whit these formalisms and that some of the proofs can be sketched. Three ideas are also put forward to brake the direct relationship (infinite hierarchy) induced by the size of the considered alphabet and the number of the membranes needed in a P system (with traces) to generate recursively enumerable languages on the chosen alphabet.