Title: Spacetime Substantivalism 29: The Mechanism of Antimatter Disappearance and Matter Existence and Its Relation to Proton Stability —— On Poisson's Equation as the Common Founder of General Relativity and Quantum Mechanics Abstract: This paper, through an audit of the core equations of physics—Poisson's equation and its derivatives—reveals a truth long obscured by the academic community: both General Relativity (GR) and Quantum Mechanics (QM) are founded upon the mathematical structure of Poisson's equation. The two have never been divided; the so-called "incompatibility" is merely a difference in the description of the same substantial spacetime constitutive law at different resolutions. Based on the audit of mathematical constitutive logic and the completion of the missing link "micro-curvature," this paper demonstrates the geometric necessity of antimatter disappearance and the constitutive foundation of proton stability, while clarifying the hierarchical misalignment with the Theory of Objectivity (TO). Keywords: Poisson's equation; General Relativity; Quantum Mechanics; substantial spacetime; logical matrix; micro-curvature; proton stability; antimatter disappearance 标题: 时空实体论 29:反物质消失与物质存在机制及其与质子稳定性的关系——论泊松方程才是广义相对论与量子力学的共同奠基者 摘要: 本文通过对物理学核心算式——泊松方程及其衍生形式的审计,揭示了一个被学界长期遮蔽的真相:广义相对论(GR)与量子力学(QM)均建立在泊松方程的数学结构之上 。两者从未分裂,所谓“不统一”仅仅是对同一实体时空本构在不同分辨率下的描述差异 。在数学本构逻辑审计以及补全“微观弯曲”这一中间环节的基础上,本文论证了反物质消失的几何必然性与质子稳定性的本构基础,并对客观性理论(TO)的层级错位做出澄清 。 主题词: 泊松方程;广义相对论;量子力学;实体时空;逻辑母体;微观弯曲;质子稳定性;反物质消失