Final answer:
The point where even light cannot escape a black hole is called the event horizon, a boundary where escape velocity equals the speed of light.
Step-by-step explanation:
The point at which even an outwardly directed light ray is pulled into a black hole is called the event horizon. The event horizon is the boundary beyond which nothing, not even light, can escape from within the black hole. It represents the surface where the escape velocity equals the speed of light. Each black hole is also thought to have a singularity at its center, which is a point of infinite density and zero volume. According to the theory of relativity, if a person or object passes through the event horizon, they would experience a region where space and time are distorted to such an extent that their path inevitably leads to the singularity at the center of the black hole, where known physical laws cease to describe the environment accurately.