Clocks at the top of a tall building run faster than clocks at ground level
Some trivia is so bizarre it forces you to rethink your entire understanding of the world. Check out the fact below, see how others reacted, and scroll down to dive into the verified science and history behind it.
Einstein's general theory of relativity predicts that time passes more slowly in stronger gravitational fields. At higher altitudes, gravity is slightly weaker, so time passes slightly faster. The effect has been measured and confirmed: a clock on the 100th floor of a building is measurably ahead of a clock in the basement over time. GPS satellites must account for this effect — their onboard clocks run about 38 microseconds fast per day due to the weaker gravity at their altitude, which is corrected in their software. Without this correction, GPS would drift by 10km per day.
We experience time as absolute and universal — a clock is a clock. Discovering that your head ages slightly faster than your feet (due to being further from Earth's centre of mass) makes time feel genuinely subjective at a physical level.
The Science Behind It
Einstein's general theory of relativity predicts that time passes more slowly in stronger gravitational fields. At higher altitudes, gravity is slightly weaker, so time passes slightly faster. The effect has been measured and confirmed: a clock on the 100th floor of a building is measurably ahead of a clock in the basement over time. GPS satellites must account for this effect — their onboard clocks run about 38 microseconds fast per day due to the weaker gravity at their altitude, which is corrected in their software. Without this correction, GPS would drift by 10km per day.
Why Your Brain Finds This Hard to Believe
Sources & Verification
OddlyHuman Editors
VerifiedWritten and fact-checked by the OddlyHuman Behavioral Science Team. We verify all psychological, sociological, and historical claims against peer-reviewed journals, primary sources, and established encyclopedias to bring you accurate insights.
Read our Editorial Guidelines →“Clocks at altitude run faster than clocks at ground level — time passes more slowly in stronger gravity. GPS satellites must correct for this; without it, navigation would drift 10km per day. ⏱️ #OddlyHuman”