Atomic clock

Atomic clock

An atomic clock is based on the frequency of the oscillation between two energy states of certain atoms or molecules. These vibrations are not affected by external forces.

The operation of the cesium clock, used to define the fundamental unit of time in the International System of Units, is based on the measurement of the frequency of the radiation absorbed by a cesium atom when passing from a lower energy state to one higher.

The first atomic clock was manufactured in 1948. The father of this new device was the American Willard Frank Libby who took two years to translate his ideas into a practical model.

The vaporized cesium atoms vibrate at a very high frequency. Another high frequency is induced to induce a resonance phenomenon in atoms that have a very precise value of 9,192,631,770 hertz or oscillations per second. This frequency is measured by reducing it to a single hertz. This frequency is perfectly usable for a watch, which will have an error of approximately one second every 300,000 years.

In 1967 the vibrations of the cesium atom, an absolute magnitude, were taken as a reference for the definition of the second, as opposed to that used previously. Specifically, this definition says that a second is 9,192,631,770 times the period of radiation corresponding to the jump between the two levels of the hyperfine structure of the fundamental state of the atoms of the nucleus Cesium 133.

But it has gone further in the search for more precise time with new electronic refinements and taking advantage of the possibilities that physics allows. Thus, in 1969 a clock was achieved with an error rate of only one second every 1.7 million years, using the vibrations of the ammonia atom.

The diffusion of these advanced clocks has had a great influence on everyday life since, after various international agreements, there is a transfer of data from atomic clocks around the world. In this way, they are regulated from the time broadcast by radio and television stations around the world, to the frequency of electric power, or air navigation, satellite control, etc. are regulated.

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