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What is the time?
From a physics perspective, time actually represents the regular movement of objects!
When we observe the sun, the moon and the stars, we have the concept of one hour and one second a year. With the advancement of science and technology, people are not satisfied with the use of natural law timing and hope to define time through physical laws. And the atomic clock quartz clock uses the vibration timing of the quartz crystal, which is about 1 second per 270 years. The electromagnetic wave timing between the two fine structures of the helium atom can reach tens of millions of years or even billions of years. Because of its high precision, people use it as a "second" definition of high-precision atomic clocks. It plays an important role in aerospace and physics research. What is going on?
Click on the video to see it!