Bridging Membrane and Reaction Systems - Further Results and Research Topics

This paper continues an investigation into bridging two research areas con- cerned with natural computing: membrane computing and reaction systems. More specif- ically, the paper considers a transfer of two assumptions/axioms of reaction systems, non- permanency and the threshold assumption, into the framework of membrane computing. It is proved that: SN P systems with non-permanency of spikes assumption charac- terize the semilinear sets of numbers, and symport/antiport P systems with threshold assumption (translated as ! multiplicity of objects) can solve SAT in polynomial time. Also, several open research problems are stated.