AbstractCurrent models of blood coagulation rely predominantly on mechanistic cascade representations that fail to capture the complex, multiscale dynamics of hemostasis. We propose a novel theoretical framework that reconceptualizes the hemostatic system as a high-dimensional coherence field where phase relationships, not concentrations or states, constitute the fundamental organizing principle. In this model, the physiological “don’t clot” state represents a metastable attractor actively maintained through phase coherence across multiple oscillatory subsystems. Observable properties like platelet activation, endothelial integrity, and coagulation factor concentrations are surface manifestations of underlying phase dynamics. Pathological thrombosis occurs not through simple cascade activation, but via coherence collapse—a phase transition in which the system loses its ability to maintain anti-thrombotic stability and becomes trapped in a nonergodic pro-coagulant state. We develop both microscopic (Kuramoto oscillator) and mesoscopic (partial differential equation) descriptions of this process, showing how local coherence collapse can propagate through competitive entrainment dynamics. This framework explains phenomena poorly addressed by current models, including the spatial heterogeneity of atherothrombosis, the systemic coagulopathy of inflammatory states, and the context-dependent nature of clotting risk. We outline a mathematical formulation based on coupled oscillator dynamics and propose experimental approaches to validate this coherence-based model of hemostasis. Specifically, we predict that the variance of single-platelet Ca²⁺ phase lag rises more than twofold within five seconds of injury in microfluidic models, providing a quantitative test of coherence collapse preceding clot formation. Keywordsblood coagulation, dynamical systems, phase transitions, coherence, thrombosis, nonergodic systems, hemostasis, nonlinear dynamics, complex systems, attractor, partial differential equations, multilevel selection