When you check your GPS

Every advance in measuring time has involved a new science. We progressed through –

  • Astronomy: Sundials had a fair amount of margin of error
  • Dynamics: Thanks to Galileo, we had pendulums and higher accuracy
  • Electromagnetics: The discovery of Quartz gave us microsecond accuracy
  • Quantum mechanics: Atomic clocks, then, led us to nano second accuracy

At the start of the 21st century, Quartz’s microsecond-level accuracy was a revelation. It enabled modern day computers which need precise time measurement.

Then, Niels Bohr’s observation of the consistency of the Cesium atom led to the use of Cesium by the “International Conference of Weighs and Measures” in 1967 to adjust any errors from Quartz.

The power of accurate measurement of time is that measuring time is key to measuring space. Every time we glance down at our phone to find our location, we’re triangulating between at least 4 of 24 atomic clocks that tell us our location based on the last measured time (mindblowing!). Of course, we know this as the Global Positioning System or GPS.

“The next time you look down at your watch, think of the embedded layers of human ingenuity that make this all possible. As more progress happens, layers of ingenuity get buried. But, this can also obscure just how far we’ve come.” | Steven Johnson


Hat tip: How we got to now by Steven Johnson