What is the highest timing instrument at present?

The most accurate timing tool is the atomic clock. At present, the accumulated error of the most accurate atomic clock in the world in one million years is only/1 second!

The clock commonly used by people has an annual accuracy of about 1 minute, which has no influence on daily life, but more accurate timing tools are needed in demanding production and scientific research. At present, the most accurate timing tool in the world is the atomic clock, which appeared in the 1950s. Atomic clocks use electromagnetic waves emitted by atoms when they absorb or release energy to time. Because this kind of electromagnetic wave is very stable and controlled by a series of precision instruments, the timing of the atomic clock can be very accurate. Now the elements used in atomic clocks are hydrogen, cesium, rubidium and so on. The accuracy of atomic clock can reach every 20 million years 1 second. This provides a strong guarantee for astronomy, navigation and space flight.

fundamental principle

According to the basic principle of atomic physics, atoms absorb or release electromagnetic energy according to the energy difference of different electron arrangement orders, that is, the energy difference of different electron layers around the nucleus. The electromagnetic energy here is discontinuous. When an atom transitions from an "energy state" to a low "energy state", it will release electromagnetic waves. The characteristic frequency of this electromagnetic wave is discontinuous, which is what people call the * * * vibration frequency. The * * vibration frequency of the same atom is certain-for example, the * * vibration frequency of cesium 133 is 9 192 63 1 770Hz. Therefore, cesium atoms are used as a metronome to maintain a highly accurate time.