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.

Related concepts

Schwarzschild metric

Schwarzschild radius at r=2GM/c² marks the event horizon

Derivation of the Schwarzschild solution

Schwarzschild solution describes spacetime around a massive, non-rotating spherical mass

Spacetime

How does time bend around massive objects?

Gravitational lensing formalism

Light bends around massive objects due to spacetime curvature

nothing with mass can reach the speed of light

Why can't you ever see a car zoom by at the speed of light?

Kerr metric

Kerr metric describes rotating black hole spacetime

Swipe through 100 ML concepts daily