Classical electromagnetic theory holds that light is a self-excited continuous electromagnetic wave propagating in vacuum. Electric and magnetic fields originate from charge sources, and light waves are analogous to spatially extended mechanical waves such as water waves that transmit electromagnetic force. This theory contains an irreconcilable core logical paradox: photons carry no net electric charge, have no rest mass, and inherently travel at a constant speed of light, yet they continuously produce observable alternating electromagnetic signals. The physical origin of this phenomenon cannot be self-consistently explained by the classical charge radiation model. This paper establishes a purely particle-based model: the essence of light consists of independent high-speed pure energy particles with no inherent charge or rest mass, permanently maintaining the speed of light, and no substance can hinder their intrinsic motion. The fundamental driving force for photon propagation stems from the particle’s intrinsic spin and inherent vibration perpendicular to its propagation direction, rather than mutual excitation between electric and magnetic fields. During propagation, the high-speed spin and vibration of photons continuously perturb the surrounding space. Alternating electric and magnetic fluctuations are merely secondary side effects derived from particle motion, instead of the power source that propels light forward. At the moment a single photon is generated, it locks a unique vibration orientation within the full 360° space perpendicular to its propagation path. This angle remains permanently constant without collisions or other external interactions. This paper puts forward an innovative core viewpoint: experimental detection can clearly capture alternating electric and magnetic response signals along photon propagation paths, and these objective experimental observations must be fully respected. However, light itself is by no means an electromagnetic wave generated by charge radiation as defined in classical theory. As photons pass through a region, they only produce transient apparent electromagnetic side effects and do not possess truly long-lived electric or magnetic fields. The alternating electromagnetic responses corresponding to photons are not electrostatic radiation waves excited by charges, but transient dynamic spatial energy gradient appearances formed by the combined perturbation of space via the photon’s energy-body spin and reciprocating vibration. Alternating electric and magnetic fluctuations are completely attached to photon motion as subsidiary byproducts; it is logically erroneous to reverse causality and claim electromagnetic interactions push photons forward. Periodic alternating electric and magnetic signals captured by detection equipment only represent temporary spatial energy undulations perturbed by high-speed photon motion. Once a photon departs a region, the spatial energy distribution immediately restores uniformity, and temporary gradient fluctuations vanish without leaving stable, persistent electric or magnetic fields. Electromagnetic waves radiated by charges rely on static charge fields: stable long-lived electric and magnetic fields persist as long as charges exist, and disappear instantaneously once charges are removed. Polarization experiments can intuitively verify the constant vibration angle and stable particle ontology of photons. The innate ability of photons to perturb space and generate transient electromagnetic gradients forms the fundamental origin of electric charge in physical particles. Free unbound photons produce fleeting energy perturbation gradients that only temporarily manifest electromagnetic appearances without sustained charge characteristics. When large quantities of high-energy photons undergo strong self-locking confinement, their spin and vibration postures are permanently fixed. Originally transient fluctuating spatial energy density gradients transform into stable steady-state gradients, externally manifesting as the fixed unit electric charge carried by electrons and protons, which generate physical charged particles capable of sustaining true, long-lived electric and magnetic fields. This paper strictly distinguishes transient perturbation side effects of particles from genuine long-lived electromagnetic fields produced by charges, thoroughly negates the classical definition of photons as mediators of electromagnetic interaction, fully elaborates two propagation mechanisms: lossless transmission in vacuum and energy attenuation via medium coupling, resolves the theoretical paradox of charge-free, massless light-speed energy particles generating observable alternating electromagnetic signals, clarifies the causal relationship between photon motion and electromagnetic effects, and forms a complete causal chain linking photon motion to the origin of electric charge in microscopic physical particles.
Jiaqing Yan (Thu,) studied this question.