The Nature of Light Pressure (Final Version)

Traditional theories of light pressure usually attribute it to particle impact and momentum transfer of photons on the surface of objects. Although this model can describe the generation of pressure formally, it has an inherent contradiction with the basic physical fact that photons have no rest mass. Based on energy matching, resonant absorption and thermal effects, this paper reinterprets the physical nature of light pressure. It is pointed out that light pressure does not originate from physical collision, but occurs only when the photon energy matches the energy level frequency of matter; the absorbed energy intensifies the thermal motion of microscopic particles, thereby producing a macroscopic mechanical effect. Different materials show obvious differences due to different absorption bands: black objects have wide absorption bands and stronger light pressure, while white objects have less absorption and weaker light pressure. This explanation is logically self-consistent and in line with basic physical laws, revealing the real process of light-matter interaction more essentially and providing a more rigorous theoretical basis for the unified understanding of light pressure phenomena.