Before 1965, physicists thought Black Holes might just be mathematical quirks that required perfect symmetry to form. Roger Penrose changed physics forever by proving that singularities are inevitable.

He introduced the concept of a Trapped Surface: a region where gravity is so strong that all light rays—even those trying to move outward—are bent inward.

To prove this, he utilized the focusing of light rays, governed by the Raychaudhuri equation. The critical inequality showing that light rays