Fire Without Flow: A Coherence-Geometric Model of Self-Sustained Reactive and Fluid-Like Dynamics

This paper develops a coherence-geometric model of self-sustained reactive and fluid-like dynamics in which fire-like organization emerges from coupled amplitude, thermal, and phase fields. Rather than taking material velocity, momentum transport, or multi-species combustion chemistry as primitive, the model uses phase-driven coherence flux, thermal activation, saturation, diffusion, and curvature-mediated redistribution to generate reactive structure. A two-dimensional implementation produces several distinct regimes within the same coherence-governed architecture: an early diffusive “firefall” transient of filamentary ignition fronts, persistent laminar-like plume structures, a high-intensity flickering regime with broad intermittent flame fronts, and a phase-transition-like regime exhibiting nucleation, growth, interaction, and coalescence of bubble-like domains. These behaviors are interpreted through different balances among curvature-driven amplitude relaxation (CDAR), curvature-driven activation dynamics (CDAD), and curvature-driven transport (CDT). The paper also examines the relationship between the reduced reactive core and an optional fluid-active transport sector incorporating buoyant curl, advection, and pressure projection. The results demonstrate how substantially different reactive, flow-like, and phase-transition behaviors can arise from a shared amplitude–thermal–phase substrate under different forcing and transport realizations. Supporting Python scripts for the firefall/laminar, high-intensity turbulent-like, and boiling/nucleation regimes are included with the archival record. CGI Internal ID: CGI-RSR-000043