All substances in the universe originate from light energy. Photons represent freeflowing primordial energy. Elementary particles including protons, neutrons and electrons are the firstformed material units generated after photons are confined within microscale spaces. Macroscopic objects such as rocks and planets are assembled stepbystep from these elementary particles. Wellverified mathematical formulas governing gravitational force, Coulomb electromagnetic force and strong nuclear force have mature computational frameworks in modern physics. Current physical theories master forcecalculation rules yet overlook a core fundamental problem: the origin of fundamental interactions. Mainstream physical frameworks interpret gravity, electromagnetic force and strong force separately via distinct models, namely spacetime curvature and gaugebosonbased quantum field theories, lacking a unified underlying origin. This paper puts forward a core premise that all matter is confined light energy. The hierarchical cosmicevolution sequence is clarified: confined freeflowing photons produce elementary particles; protons and neutrons form atomic nuclei; positive proton charges bind negativelycharged electrons to build atoms; atoms form molecules, which further aggregate into bulk matter. Qualitative logical reasoning demonstrates forcegenerating mechanisms. Unconfined free photons exhibit no mutual interactions. After photons are trapped inside protons, neutrons and electrons, the innate tendency of confined photons to restore free motion generates three fundamental forces. Corresponding to confinement scales from nuclear microcosm, atomic intermediate layer to astronomical macroscopic scale, strong nuclear force, electromagnetic force and universal gravitation emerge sequentially. Established physical formulas are retained without revision. This paper sorts out the causal evolutionary chain: light energyelementary particlesatomic nucleiatomsmoleculesmacroscopic matterfundamental forces, supplementing the missing originbased theory within existing physics systems.
Jiaqing Yan (Sun,) studied this question.