AS102 Study Guide - Final Guide: Gravitational Redshift
Document Summary
The resulting point mass is called a black hole because if we shine light on it, the light will be captured by the black hole and will not be reflected. The general theory of relativity predicts the existence of black holes. As the star"s matter becomes compressed to enormous densities, the strength of gravity at the surface of the shrinking sphere also increases significantly. According to relativity, the space right around the star becomes so highly curved that it closes in on itself. Photons flying outward at an angle from the star"s surface arc back inward, while photons that fly straight outward undergo such a strong gravitational redshift that they lose all their energy and cease to exist. The black hole"s mass is at the bottom of the funnel, or hole in spacetime, improperly shown here because actually the gravitational "well" is infinitely deep.
