Stochastic Analysis of The Viability of a Protocell

Notions of viability and viability boundaries appear in many different fields, including protocell research as it is within the field of Artificial Life (Alife). However, we do not have any common methodology or a general principle to measure/understand the viability of a protocell. Much of the research around protocells is concerned in one way or another with the protocells being ‘viable’, so it is important to have a good formal understanding of what viability actually is. In this work, we use stochastic chemical kinetics, which have been instrumental in accurately simulating various biological processes, to expand on some recent efforts in formalizing the viability of a protocell. We discuss key differences between the stochastic and deterministic models and demonstrate how stochasticity can expand on the formalism of viability. Finally, we argue that a more stochastic interpretation of the notion of viability boundaries is more appropriate for at least some systems where small numbers of reactants play vital roles.