Background: Special relativity is founded on the postulate of constant light speed. However, attempts to resolve cosmological enigmas through variable speed of light (VSL) proposals often lead to contradictions. This study introduces a unified formulation that reconciles both theoretical perspectives.
Objective: To derive equations that incorporate light speed variability without compromising its observational constancy.
Methodology: Einstein’s mathematical approach to space and time equations in special relativity is resumed, omitting (c) as a postulate and introducing the concept of Corrective Reciprocal Transfer (CRT), a new computational tool developed by the author.
Results: A new velocity addition equation is derived, incorporating a variable speed (c′). When this variable is introduced into the formulation, the equation yields c as a constant—without having imposed it as an initial postulate. This finding necessitates a redefinition of what is meant by light speed, opening new interpretations of the phenomenon. The result supports the architecture of the proposed model and paves the way for reinterpreting the structure of space-time.
Conclusion: The reformulation of c within the mathematical framework enables the unification of both theories without contradiction, extending classical relativistic equations of space-time and mass-energy. This new theoretical perspective offers a coherent approach to cosmological enigmas such as the origin of the universe, the horizon problem, or cosmic flatness, while preserving the classical constancy of c.
Keywords: VSL (Variable Speed of Light), critical density, horizon problem, vacuum catastrophe, cosmological constant, lambda problem, dark matter, dark energy, multiverse, accelerated expansion, Lambda problem, vacuum catastrophe, Lambda-CDM model, cosmic inflation.