The length of a second could be about to change as German Scientists have found a way to create world’s most accurate clock.

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Scientists believe optical clocks are going to replace the atomic clock as a new and far more accurate standard. Currently, the time of the day is decided based on 500 atomic clocks that are spread out throughout the world. These clocks have helped us keep track of time each and every day for half a century, working by measuring atomic oscillations. German researchers have discovered a new way to tell time with an accuracy that has never been employed before, findings which are published at length in the Optical Society of America journal Optica.

Clocks work by keeping track of a constantly recurring event that has a specific frequency. In grandfather clocks, you can watch this frequency with their swinging pendulum. In microwave atomic clocks (which we use in our GPS, cell phones and electric power grids), the oscillation of the cesium atom is the frequency at inside the microwave region of the electromagnetic spectrum. A second is measured by the International System of Units, and is the time during 9,191,631,770 cycles of the microwave signal that is being produced by the cesium jiggling.

Optical clocks work in a similar way to microwave atomic clocks, but they measure atoms or ions that are oscillating at frequencies that are 100,000 times greater in cesium. Optical clocks are far more precise than atomic clocks because they have faster vibrations, which allows them to tick faster. The reason these more accurate solutions were not used in the past was because they had long downtimes between their measurements.

Researchers at The National Metrology Institute of Germany fixed these problems by combining an optical clock with a maser (a device similar to a laser that works in the microwave spectral range). The maser’s microwave frequencies were then spliced by a frequency comb in order to match the speed of the ticks of the optical clock. The maser acts as a pendulum would on a grandfather clock, keeping the optical clock working even in the event of downtime. Christian Grebing, lead researcher of the team says the maser runs on its own, creating its own stability even when the optical clock is paused.

If optical clocks were incorporated into our infrastructure of time, the definition of what a second is would completely change. Grebing and his team were able to compare their optical clock’s frequency to the current rate of a second and their machine has the lowest measure of uncertainty of any clock that has ever existed. If the clock ticked for 14 billion years, which is the amount of time the universe has existed, it would only be “off” time by about 100 seconds. Grebing says the research was able to show that even with the downtimes of optical clocks of today; our timekeeping can still be improved.

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