Self-sustaining autocatalytic networks within open-ended reaction systems

Abstract: Given any finite and closed chemical reaction system, it is possible to efficiently determine whether or not it contains a `self-sustaining and collectively autocatalytic' subset of reactions, and to find such subsets when they exist. However, for systems that are potentially open-ended (for example, when no prescribed upper bound is placed on the complexity or size/length of molecules types), the theory developed for the finite case breaks down. We investigate a number of subtleties that arise in such systems that are absent in the finite setting, and present several new results.