Four Fundamental Forces and the Unified Theory of Gravitational–Strong Interaction Homology

Modern physics classifies gravitation, electromagnetism, strong interaction, and weak interaction as four completely independent fundamental forces, and has long been unable to unify macroscopic gravity and microscopic nuclear force. Traditional theories introduce additional assumptions such as gluon mediation and spacetime curvature, which artificially increase the complexity of physical models and deviate from the original law of mass interaction. This paper returns to the basic observable physical quantities: mass, distance, electric charge, and energy conversion, and redefines the underlying mechanism of the four fundamental interactions. Electromagnetism relies on charge interaction, and the weak interaction is essentially neutron decay with energy release; both are unrelated to the mass attraction mechanism. Gravitation and strong interaction are homologous pure mass-coupling interactions that follow exactly the same inverse-square law mechanical structure. The two sets of interaction formulas have no artificial scope restrictions and are mathematically self-consistent in the whole domain. They only correspond to coupling constants of different orders of magnitude according to different spatial scales. At the extremely short scale of the atomic nucleus, the coupling constant is very large, showing the strong nuclear force; at the macroscopic scale, the coupling constant is very small, showing universal gravitation. As the distance increases, the strong interaction decays naturally to a negligible level following the inverse-square law, without artificial boundaries or fictitious force carriers. This theory eliminates redundant hypotheses, completes the deep unification of macroscopic gravity and microscopic strong force, and constructs a concise, self-consistent, and quantifiable new system of fundamental physics, which has important value for the innovation of basic theory.