Nine, neutrino missing unsolved cases
The concept of neutrino was put forward by Pauli, a Swiss-Austrian physicist, in 1930, and was named by Fermi, another Italian physicist. In the observed process of free neutrons decaying into protons and electrons, some lost energy is not counted. In order to save the law of conservation of energy and momentum, Pauli proposed that the lost energy may be taken away by an undetectable, light and uncharged particle called neutrino. They have almost no interaction with other substances, and they are extremely penetrating, passing through everything they encounter at a speed close to the speed of light.
Photons produced by thermonuclear reaction in the central region of the sun have short free paths in high temperature and high density environment. After numerous collisions and cycles, it takes 6.5438+million years to reach the surface of the sun. It takes only 8 minutes for people on earth to receive solar photons from the surface of the sun to reach the earth, but the time when these photons were generated from the center of the sun was 6.5438+million years ago. Only neutrinos were just produced from the sun center more than 8 minutes ago, and only they came to people with the latest information of the sun center. If people can observe these neutrinos continuously, once the number of neutrinos drops sharply or stops transmitting, it shows that the continuous supply of photons can last for 65.438+million years, which plays an early warning role.