“Is it possible to have clocks accurate to a billionth of a second?”
We use clocks to keep time everyday. Whether it be for scheduling flights or processing the internet, civilization depends on clock technology to keep everything in balance. Clocks work by measuring the oscillations of a pattern, such as measuring how long a pendulum takes to swing back and forth or the earth to move around the sun. However, such machines are not always perfect. Since clocks (of all types) are physical objects, they are subject to the physical laws of the universe. Consequentially, these contraptions are prone to perturbation, which in effect makes them liable to becoming out of sync with other clocks. These inconsistencies add up over time (pun defiantly intended), and if they go on for too long, then drastic consequences can happen. For example, high speed finance trading could go asunder, which would have devastating effects on the global economy.
So how can we make a clock so accurate that we would never have to worry about civilization collapsing?
Well, luckily for people anxious about such an event, scientists and engineers have constructed marvelous devices known as atomic clocks. Atomic clocks work by measuring the internal oscillation of a cesium atom. Cesium atoms vibrate over 9 billion times in one second, and atomic clocks base their own measurements off such vibrations. Atomic clocks that are so accurate that commercial units are accurate to one second in 3 million years! Because of this genius design, scientists and engineers now base the unit of the second is based upon how atomic clocks can measure the osculation of a cesium atom.