Periodically Forced Bifurcation of a Vesicular System: From Physical Life to Biochemical Overlay

This article extends a nonlinear dynamical model of prebiotic vesicles by explicitly connecting it to the conceptual distinction between physical life and its later biochemical overlay. We assume a periodic hydration–dehydration forcing that generates oscillations in membrane tension and pore formation. By introducing an internal oxidative load variable, we show that increasing environmental oxidative pressure drives bifurcations between dynamical regimes: smooth periodic response, pulsed permeability (limit cycle), and persistent destabilization. We argue that the pulsed regime represents a purely physical regulatory principle, which may have preceded and later been stabilized by biochemical mechanisms. In this framework, biochemistry does not create regulation from nothing; it formalizes and refines pre-existing physical dynamical structures.