Your phone's location depends on Einstein’s theories of relativity

Technology · Published 26 October 2026 Swipe more like this →

In short: To find your location within meters, your phone listens to atomic clocks orbiting 20,200 km above Earth. This video explains the physics and engineering required to keep these signals accurate enough for daily use.

GPS relies on trilateration, where a device calculates its position by timing signals from multiple satellites. Because the satellites move at high speeds and exist in different gravitational fields, engineers must apply Einstein's relativity corrections—adjusting for a time difference of about 38 microseconds every day.

The system is supported by global networks like Galileo, GLONASS, and BeiDou. Beyond navigation, GPS time provides a hidden backbone for essential infrastructure, including power grids, banking systems, and cellular networks.

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