The 4-Sphere model of cosmology

The 4-Sphere Model of Cosmology is a geometrical framework in which the observable Universe is represented as the three-dimensional hypersurface (S^3) of a four-dimensional hypersphere. Its cosmological evolution is described through the growth of the hypersphere's radius, assumed to be proportional to cosmic time. The model explores whether some features conventionally attributed to dark matter, dark energy, and the standard cosmological expansion framework can instead be interpreted through hyperspherical geometry and its consequences for local gravitational dynamics. A central element of the framework is the role assigned to the Cosmic Microwave Background (CMB) in the global equilibrium of the hyperspherical configuration. The model proposes a geometrical interpretation of energy conservation in which the three-dimensional description of the expanding hypersurface includes an effective work term associated with the preservation of the four-dimensional geometry. The framework is still under development. Its assumptions, mathematical formulations, and observational implications are being investigated through separate studies concerning cosmological geometry, primordial abundances, and gravitational dynamics.