Gravitational singularity

Ever wondered why some things can't escape a black hole's pull?

Imagine you're holding a balloon filled with helium; if you let go, it floats away. Now, think of a black hole as a cosmic balloon with a super strong vacuum.

A black hole's gravity is so strong that nothing, not even light, can escape once it passes a certain boundary called the Schwarzschild radius. This boundary is like the balloon's vacuum, beyond which there's no escape.

Example

If the balloon's vacuum was as strong as a black hole's gravity, the helium would never come back.

Remember this

The Schwarzschild radius is the point where the escape velocity equals the speed of light.

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

Related concepts

Derivation of the Schwarzschild solution

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

Schwarzschild radius

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Schwarzschild metric

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Black hole information paradox

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Kerr metric

Kerr metric describes rotating black hole spacetime

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