PFUS 55.0 Universal Ultimate Unified Theory: Universal Compatibility and Paradigm Transcendence of the Dirac Equation — Double-Cone Convergence Constraint Formula and Ontological Origin of Spin

This paper establishes the universal compatibility, ontological reconstruction, and paradigm transcendence of the Dirac equation under the PFUS 55.0 Universal Ultimate Unified Theory. It is rigorously proved that the Dirac equation is not a fundamental or ontological equation, but a low-dimensional constrained projection of the PFUS universal ontological field under four-dimensional, low-energy, weak-coupling conditions. This work proposes and derives the PFUS Double-Cone Convergence Constraint Formula, which is an independent primordial ontological formula of the PFUS system, not a Dirac-type equation, not a deformation of the Dirac equation, and not a generalization of the Dirac equation. It serves as the underlying physical and mathematical law that governs the origin of spin-1/2, particle generation, dimensional projection, and cosmic steady state. During upper-cone convergence and flux self-regulation, the ontological spin value is slightly greater than 1/2 with weak intrinsic oscillation for flux self-correction, then converges precisely to the observed steady value 1/2 in four-dimensional projection. Microscopic particles exhibit tighter convergence near ideal 1/2, while macroscopic structures retain mild redundancy before steady convergence. This theory unifies quantum mechanics, relativity, particle physics, and cosmology under a single ontological framework, realizes a complete paradigm shift from phenomenology to ontology, and provides the ultimate underlying foundation for all relativistic quantum phenomena.