Deriving Black Hole Geometry from Radiation.

This article introduces a photogravitational framework for interpreting the gravitational constant G through observational astrophysical parameters. By defining the photogravitational index Φ, which relates luminosity to gravitational field properties, the paper derives G using measurable quantities such as mass, radius, and emitted radiation. A case study of Cygnus X-1 demonstrates how this formulation yields values consistent with the known gravitational constant. At the Schwarzschild boundary, Φ simplifies into a purely geometric expression, independent of mass or radius, suggesting a regime where radiation becomes indistinguishable from spatial geometry. While General Relativity describes gravitation as the curvature of spacetime due to mass-energy, the photogravitational approach offers a complementary formulation: gravity as an emergent expression of radiation. Rather than replacing GR, this perspective aims to enrich our understanding of how curvature may arise directly from luminous structures.