the Pauli exclusion principle forbids

Can two identical particles ever share the same spot in quantum mechanics?

Imagine you have two identical smartphones, and you want to put them in the same pocket. You quickly realize this isn't possible because you can't fit them both there without them getting squished.

In quantum mechanics, it's like having two identical smartphones trying to fit into the same pocket. They can't both occupy the same space without violating a fundamental rule.

Example

If you try to put two electrons in the same orbital (like trying to fit two smartphones in one pocket), they must have different spins (like having one phone with a case and the other without).

Remember this

The Pauli exclusion principle ensures that no two identical fermions can occupy the same quantum state.

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

Related concepts

Electron configuration

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Pauli exclusion principle

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