Part 5/9:
The Eddington limit represents the maximum luminosity a black hole can achieve, where the outward radiation pressure from infalling matter balances gravitational pull. In usual scenarios, a black hole shouldn't exceed this boundary. Historical figures in astrophysics, like Sir Arthur Stanley Eddington, underline the significance of this limit as they paved the way for our understanding of stars' luminosity and mass relationships.
As stars grow, their gravitational force increases, and without adequate counter-pressure, they would implode. Eddington posited that the pressure exerted by radiation—a consequence of nuclear fusion—was integral to maintaining equilibrium within stars. He deduced that a star's luminosity increases significantly with mass.