Mind-Bending Math & GamesInfinity

Hilbert's Hotel

A full hotel with infinitely many rooms can always fit more guests

The sign says NO VACANCY: infinitely many rooms, all taken. A new guest walks in, then an endless busload. Where does everyone sleep?

You'll find out

  • How a full hotel still has room
  • Where an endless busload sleeps
  • Whether every infinity is the same size

Why it matters

Infinity isn't just philosophy: it proves some problems can never be solved by any computer, however fast.

About 3 min6 interactive slides · 5 questionsLesson 9 · Zone 1

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