Spacetime Substantivalism 38 The Electrodynamic Nature of Gravitational Radiation and the Reduction of Vacuum Constitutive Metric — Critique and Revision of the Geometrical Spacetime Paradigm Based on Multi-Messenger Astronomical Empiricism

Title: Spacetime Substantivalism 38: The Electrodynamic Nature of Gravitational Radiation and the Reduction of Vacuum Constitutive Metric — Critique and Revision of the Geometrical Spacetime Paradigm Based on Multi-Messenger Astronomical Empiricism Abstract: In 1865, Maxwell established the electromagnetic nature of light waves, revealing the constitutive characteristics of vacuum electrodynamics and achieving the first paradigmatic unification in the history of fundamental physics. In the ensuing century, classical gravitational theory interpreted the dynamical compensation mechanism of local electromagnetic energy flux as the geometrical curvature of an abstract four-dimensional spacetime manifold. With the empirical confirmation by multi-messenger astronomy that the propagation speed of gravitational radiation (gravitational waves) is strictly equal to the speed of light in vacuum $(v_{g}=c)$, fundamental physics has ushered in a comprehensive return to electromagnetic realism. Based on the constitutive equations of electrodynamics and the tensors of continuum mechanics, this paper conducts a thorough dynamical audit of gravitational waves, proving that gravitational waves are essentially local electromagnetic characteristic fluctuations of the ground-state substantial spacetime lattice under strong stress perturbations, while the classical relativistic geometric metric is merely a phenomenological mathematical representation of the stress deformation of this substantial medium. This research eliminates the fundamental logical rupture between macroscopic geometric manifolds and microscopic gauge fields, achieving a global unification of mass, motion, gravity, and spacetime metric at the level of Maxwell's electromagnetic constitution. Keywords: The Second Maxwell Moment; Gravitational Waves; Electromagnetic Constitutive Constants; Substantial Spacetime Dynamics; Dual Protocol; Geometrical Idealism; Paradigm Liquidation; Hugang Cui 标题: 时空实体论38:引力辐射的电动力学本质与真空本构度规的还原——基于多信使天文学实证对几何时空范式的批判与修正 摘要: 1865年,麦克斯韦建立了光波的电磁本质,揭示了真空电动力学的本构特性,实现了基础物理学史上的第一次范式大统一。在此后的一个世纪里,经典引力理论将局部电磁能通量的动力学补偿机制解释为抽象的四维时空流形的几何弯曲。随着多信使天文学实证确认引力辐射(引力波)的传播速度严格等于真空光速($v_{g}=c$),基础物理学迎来了一场对电磁实在论的全面回归。基于电动力学的本构方程和连续介质力学的张量,本文对引力波进行了彻底的动力学审计,证明引力波本质上是基态实质时空晶格在强应力扰动下的局部电磁特征涨落,而经典相对论几何度规仅仅是这种实质介质应力形变的唯象数学表征。本研究消除了宏观几何流形与微观规范场之间的根本逻辑断裂,实现了在麦克斯韦电磁本构层面上对质量、运动、引力和时空度规的全球统一。 主题词: 麦克斯韦第二时刻;引力波;电磁本构常数;实质时空动力学;双重协议;几何唯心主义;范式清算;崔虎刚