Unbounded Emptiness and Overlapping Manifestation: A Pre-Ontological Foundation for Sₐ^3 Noncommutative Geometry Grand Unified Theory with Falsifiable Predictions

The unification of quantum mechanics, general relativity, and the Standard Model (SM), as well as the first-principles explanation of free parameters in the SM, have long been unresolved fundamental problems in physics. This work establishes a complete grand unified theoretical system based on the pre-ontological framework of "Unbounded Emptiness and Overlapping Manifestation" and the Sₐ^3 noncommutative geometry, integrating core insights of string theory (T-duality), loop quantum gravity (background independence), and Connes' noncommutative geometry. Starting from the pre-ontological perspective, we identify "Unbounded Emptiness" as the ultimate substrate of existence—an unconstrained, presuppositionless origin that spontaneously emerges infinite overlapping universes, each corresponding to a self-consistent spacetime geometric configuration. Our observable universe is the unique configuration that achieves long-term stability and life compatibility, with Sₐ^3 noncommutative geometry as its core spacetime structure and Scale Self-Duality as the fundamental evolutionary constraint. The theoretical framework realizes full unification without ad hoc assumptions (no extra dimensions, supersymmetry, or free dimensionless parameters): (1) Rigorously proving the Representation Splitting Theorem on the quantum flag manifold, we derive the first-principles geometric origin of three fermion generations; (2) From the topology of the quantum flag manifold and Scale Self-Duality Axiom, we lock the fine-structure constant, fermion mass power law, and Newton's gravitational constant, resolving the 120-order-of-magnitude cosmological constant fine-tuning problem; (3) Naturally deriving S₃ quark flavor symmetry and A₄ lepton flavor symmetry, we fully reproduce the CKM and PMNS mixing matrices consistent with experimental data, and explain neutrino masses via the Type-I Seesaw mechanism; (4) Systematically proposing falsifiable predictions covering cosmology (closed S³ universe with ₖ<0), quantum gravity (high-energy photon dispersion corrections), particle physics (proton decay channels), and black hole physics (shadow size corrections), with clear test windows for current and future experiments. This work bridges metaphysics and physics, providing a self-consistent, first-principles solution to century-old unification puzzles, and offers a complete experimental verification roadmap for fundamental physics unification.