[100 challenge] DanJi’s reading note_15

[100 challenge] DanJi’s reading note_15

tremors and echoes
(The universe, the world, and us from the perspective of physicist Kim Sangwook)
Author Kim Sangwook
Publishing East Asia
Issued 2018.11.07


Even at night, you can't see many stars now. But when it was nightly, people would have seen more stars than books or TV. Venus, which shines brightly in the early evening, must have been a popular entertainer, and the Milky Way on a summer night was a free blockbuster. I don't know if I felt so vague about the universe when I was staying in Germany as a contract researcher.

Today, 1 meter is determined by the speed and time of light. In other words, the distance that light travels during a certain period of time is 1 meter. It means that the length is determined by time. As mentioned earlier in the theory of relativity, the speed of light is unchanged. Therefore, the number 299,792,458 meters per second was set. This length becomes time. Then, how do we set one second? The standard of time is also determined by light.

The current definition of one second is the time taken for the light of a particular frequency produced by the cesium atom to vibrate 9,192,631,770 times. This means that even if human civilization collapses someday in the future, someone who has seen this definition will be able to accurately recover 1 meter. Of course, you must be able to accurately count vibrations of about 9 billion times, so you must know the frequencies with tremendous accuracy. The 2005 Nobel Prize in Physics was awarded to John Hall and Theodore Hensch. Their achievement was to produce light with accurate frequencies. Recently, using this method, the frequency could be up to 19 digits. By comparison, it means that the distance between Seoul and New York can be measured with an error less than the size of an atom.

But as you know, there is matter in the world. Why? We don't know the exact answer yet, but it is clear that the amount of substances and antimatter made by twinning must be different. Substances must be produced about one-billionth more than antimatter. If it is too big or smaller, our universe will not be what it is today. If it is one-billionth, it is a fine difference enough to measure the distance between Seoul and Busan with the accuracy of millimeters. Anyway, the material of the world came from an unknown asymmetry. The right size of the warp created the world.