Three-Layer Superposition Mechanism of Spectral Shift and the Interpretation of Cyclic Universe with Galaxy Contraction

The standard cosmological model attributes the spectral redshift of extragalactic celestial objects uniformly to the expansion of cosmic space and the early evolution of the universe, adopting a single dynamic mechanism to interpret full-domain spectral shift phenomena. It fails to fully match the layered observational facts: blueshift in nearby regions, zero shift at medium distances, and universal redshift at far distances, thus carrying inherent theoretical defects. Based on an original physical framework of independently circulating local blocks, nebula collapse and contraction, and weak-coupling energy decay of photons over long distances, this paper establishes a three-layer superposition model for redshift and blueshift. This paper proposes that the universe has no global origin, no unified early or late evolutionary stages, and only countless independent spatial blocks that repeatedly complete an infinite closed-loop evolution: nebula diffusion – matter collapse – galaxy formation – high-energy jet – regenerated nebula. The spectral shift of celestial bodies is superimposed by two core mechanisms: first, the universal fundamental redshift generated by photons propagating across interstellar space over vast distances, which only produces energy attenuation without reverse energy gain; second, the dynamic Doppler shift arising from the contraction motion of galactic nebulae, which may present redshift, blueshift or zero shift. The superposition of the two mechanisms naturally forms three layers of observational characteristics: blueshift dominates nearby regions, red and blue shifts counterbalance at medium distances, and redshift prevails at far distances, which perfectly fits astronomical measurement data. Abandoning traditional paradigms such as space expansion and the Big Bang, this model provides a self-consistent interpretation of celestial spectral shift phenomena from the perspective of local celestial evolution and the physical essence of photon propagation, making up for the observational adaptation loopholes of standard cosmology.