Spatial Pressure Gravitational Theory — Flagship Manifesto & Quantum Foundation Milestone

This document serves as the flagship manifesto and milestone snapshot of the Spatial Pressure Gravitational Theory (SGT), declaring SGT's formal entry into the foundations of quantum mechanics. SGT posits that the vacuum is filled by a continuous elastic medium—"Spatial Energy"—with matter as topological defects in this medium, and gravity arising from the tension gradients produced when matter stretches the medium. Through systematic theoretical construction and multiple rounds of independent audits, SGT has achieved full closure of its classical field background—with independent numerical solutions for the Ω-A1 ODE produced, the medium-metric coupling constant rigorously derived from action variation, and five constitutional anchors verified and corrected with high precision. In the domain of quantum foundations, SGT provides A-level derivations for spin-½, identical particles, and antiparticles that are completely independent of quantum mechanical axioms—using no quantum parameters or postulates. SGT supplies a deterministic ontology for quantum mechanics: the wavefunction is the slowly-varying envelope of the medium's strain field, and entanglement is the non-separability of global PDE solutions in a classical elastic medium. This paper follows the IPSTP protocol's three-part rights confirmation structure of Conditions → Constraints → Results, strictly distinguishes proven theorems from model predictions, and publicly releases for the first time the evidence tier system for SGT's quantum docking.