Question

What is the boundary that marks the "point of no return" between a black hole and the outside universe?

Answer 1

The event horizon is the boundary that separates a black hole from the outside universe. Anything that enters the event horizon cannot escape, including light. Inside the event horizon is a singularity, a point of infinite density and zero volume.

Step-by-step explanation:

The event horizon is the boundary that marks the point of no return between a black hole and the outside universe. It is the region that separates the things trapped inside the black hole from the rest of the universe. Anything that enters the event horizon, including light, cannot escape.

Inside the event horizon, the force of gravity is so strong that space and time become extremely distorted, leading to the formation of an infinitely squeezed point called a singularity. At the singularity, the laws of physics as we know them break down, and our current mathematical tools are not able to describe it. However, from the outside, the structure of a basic black hole can be described as a singularity surrounded by an event horizon.

Answer 2

The boundary that marks the "point of no return" between a black hole and the outside universe is called the event horizon. Anything that crosses the event horizon, including light, cannot escape the black hole and is trapped inside.

Step-by-step explanation:

The boundary that marks the "point of no return" between a black hole and the outside universe is called the event horizon. It is the region surrounding the black hole where the escape velocity (the speed needed to escape the gravitational pull) equals the speed of light. Anything that crosses the event horizon, including light, cannot escape the black hole and is trapped inside.

The size of the event horizon depends on the mass of the black hole. For example, the event horizon of a black hole with the mass of the Sun would have a radius of about 3 kilometers.

Inside the event horizon, spacetime is highly curved, and the laws of physics as we know them break down. At the center of a black hole is a hypothetical point called the singularity, where matter is infinitely squeezed into zero volume and infinite density.