Quantum & RelativityRelativity

Time Runs Faster Upstairs

Atomic clocks tick faster just 33 centimeters higher

Two identical clocks: one in the basement, one in the attic. Leave them for a lifetime. Which one shows the later time, and why?

You'll find out

  • Why height changes how fast time runs
  • How far ahead your head gets
  • How small a step clocks can feel

Why it matters

The best clocks now feel a step's height, and the same effect could one day track the ground rising and sinking.

About 3 min6 interactive slides · 5 questionsLesson 237 · Zone 27

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