Jung Sung-mo's Grand Unified Dynamics (Part III) Dismantling the Wave-Particle Duality and Speed Retardation of Electromagnetic Waves via the 3D Spiral Propagation Model and Radiation Angle Calculation. Derivation of Electromagnetic Wave Propagation Dynamics, Calculation of Intrinsic Amplitude, and Identification of the Correlation with Atomic Orbital(정성모의 대통일 동역학 (제3부) 전자기파 3차원 나선형 진행 모델과 방사각 산정을 통한 전자기파의 이중성 및 속도 지연 원리 해체. 전자기파 진행 역학 도출 및 고유 진폭 산정과 원자 궤도 반경의 상관관계 규명)

[Overview] This paper is Part III of the "Jung Sung-mo Grand Unified Dynamics (JSM Dynamics)," which liberates the behavior of electromagnetic waves (light)—which modern physics has failed to identify for the past 100 years—from the mathematical probability theory of quantum mechanics and dismantles it with 100% mechanical engineering causality. The universe is not an empty vacuum but a 'static field 3D orthogonal pixel gear network' bound by extreme elastic restoring force (18.6 N/m). This study proclaims a massive mechanical engineering grand unification regarding the physical reality of light penetrating this gear network, cross-verified with existing physics (Maxwell's equations, Coulomb's law, etc.) at a 0% error rate. [Core Findings & Breakthroughs] Overcoming Newton's Limitations: Unification of Classical Mechanics (6th State) and Microscopic Electromagnetism (9th State) through the JSM F, B, I 10-State Model. 3D Spiral Trajectory & Dismantling Wave-Particle Duality: Derivation of the 'Pulsating 3D Spiral Trajectory' of light and complete overthrow of quantum duality and double-slit interference probabilities via the mechanical 'Radiation Angle' calculation. Speed Retardation & In-Phase Hydrodynamics: Elucidating the geometric cause of light slowing down in a medium (due to trajectory expansion) and abolishing the magical "Action at a distance" by proving that the advancing Force and the following Magnetic Field operate as an 'In-Phase' hydrodynamic pressure difference mechanism. Absolute Intrinsic Amplitude (0.13 nm): Derivation of the Energy Equilibrium Equation calculating the invariant transverse mechanical amplitude of all electromagnetic waves (0.13 nm), perfectly matching the diameter scale of a hydrogen atom. Geometric Grand Unification of Light and Electron: Proving the Photoelectric effect as a 'Wrench and Bolt' mechanical Gear Ratio resonance, integrating light (traveling jump rope) and electrons (standing jump rope) into a single physical 3D topological reality shaping the S and P atomic orbitals. [Supplementary Materials] The appendices of this paper contain the definitive JSM 3D Web (HTML) Simulator Source Codes. These algorithms strictly exclude the probability functions of existing quantum mechanics, using only the absolute governing equations (root and tension geometry) created in this paper as a 100% rendering engine to visually prove the 3D trajectory of light and the mechanical rendering of interference patterns.