Special Relativity misinterprets the observed constancy of the speed of light in a vacuum as the invariance of relative light speed across all inertial reference frames, confusing the physical definitions of absolute light speed and relative light speed and thus forming systematic logical paradoxes. This paper establishes a new underlying model of cosmic mass and energy: light is pure particle-form primordial energy of the universe, rather than electromagnetic waves as traditionally defined, and gamma photons represent the high-energy form of light. The speed of light is an inherent ultimate propagation rate possessed by photons by nature. It remains constant relative only to photons themselves and is unaffected by the motion of light sources, observers or transformations of reference frames. Photons have no rest mass and no electric charge, so no external force can accelerate or decelerate them — this is the fundamental physical reason for the constancy of the speed of light. The relative speed of light observed by observers follows the rules of classical kinematics: the relative speed decreases when the observer moves in the same direction as light, and increases when the observer moves in the opposite direction. Variations in observed values merely stem from differences in reference frames and never alter the intrinsic speed of photons. Essential matter is not an independent entity, but high-energy light energy confined and bound by microscopic particles. Protons, neutrons and electrons form the basic microscopic confinement structures, which trap photons moving at the speed of light within an extremely tiny space and mask their inherent property of propagating at light speed. Macroscopically, such confined states manifest as tangible matter with rest mass. When the microscopic confinement structure collapses and the binding force disappears, the trapped light energy breaks free from material constraints, reverts to its original photon state, and propagates outward at the standard speed of light in a vacuum. By distinguishing between the overall common velocity of a complete system and the relative velocity within the system, and combining the inherent physical properties of photons, this paper thoroughly resolves the reference frame paradox revealed by ground-based light speed experiments, corrects fundamental conceptual errors in Special Relativity, and constructs a logically self-consistent theoretical system covering mass-energy transformation and the propagation rules of light speed.
Jiaqing Yan (Wed,) studied this question.