How can you compress mass to light speed escape?

Schwarzschild radius

How can you compress mass to light speed escape?

Imagine you're trying to fit a heavy object into a tiny box until you can't remove it no matter how hard you try.

The Schwarzschild radius is like the smallest box you can squeeze a mass into so tightly that nothing, not even light, can escape its pull.

Example

If you squish a star's mass into a sphere with a radius of 2 kilometers, light can't escape from it.

Remember this

The Schwarzschild radius marks the boundary where escape velocity equals light speed.

Text adapted from Wikipedia, licensed under CC BY-SA 4.0.

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