If the three-body planet (and the three suns) is a system that is always changing, then the human body (and instincts, thoughts, and emotions) is also similar to such a complex constant-changing system.

There is really no solution to the three-body problem.

Except for the title, the rest of the following are excerpts from Liu Cixin’s novels.

Excerpt from The Three-Body Problem: Nothingness is Not Nothing

At this point, I was tired of it all, so I took my simple luggage and went to a temple deep in the mountains in the south.

Oh, I am not going to become a monk. I am too lazy to leave home. I just want to find a really quiet place to live for a while. The elder there was an old friend of my father's. He was very knowledgeable, but he escaped into Buddhism in his later years. According to my father, at his level, this was the only way to go. The elder took me in, and I told him that I wanted to find a quiet and worry-free way to finish my life. The elder said that it is not quiet here. It is a tourist area and there are many people who come to visit it. It is hidden in the city. If you want to be quiet and worry-free, you can have some time. I said that I was empty enough, that fame and fortune were nothing to me, and that the monks in your temple had more ordinary hearts than I did. The elder shook his head: Emptiness is not nothingness, emptiness is a kind of existence, and you have to fill yourself with the existence of emptiness. These words were very inspiring to me. Later, when I thought about it, I realized that this was not a Buddhist idea at all, but more like a certain modern physics theory. The elder also said that he would not talk to me about Buddhism for the same reason as the middle school teacher: it is useless to a person like me.

On the first night, I couldn't sleep in the monastery's cabin. I didn't expect this paradise to be so uncomfortable. The bedding became damp in the mountain fog and the bed was hard. So, in order to hypnotize me, I tried to fill myself with "empty" as the elder said: The first "empty" I created in my consciousness was the endless space, in which there was nothing, not even light, empty. of. Soon I felt that this empty universe could not make me feel peaceful at all. Instead, I felt an inexplicable restlessness in it. There is a desire in a drowning person to grab something at random.

So I created a sphere for myself in this infinite space, a small sphere with mass. But the feeling did not get better. The sphere was suspended in the middle of "empty" (for infinite space, any place is the middle). Nothing in that universe acted on it, and there was nothing on it to act on. It hangs there, never making the slightest movement or change. It is really the most accurate interpretation of death.

I created a second ball, which is the same size and mass as the original ball. Their surfaces are total reflection mirrors, reflecting each other's image, reflecting the only one in the universe besides itself. of an existence. But the situation is not much better: if the balls had no initial movement, which was my first push, they would soon be pulled together by their respective gravitational forces, and then the two balls would hang motionless against each other, still one dead symbol. If there is initial movement and no collision, they will rotate around each other under the influence of their respective gravity. No matter how you initialize, the rotation will eventually be fixed and never change, a dance of death.

I introduced a third sphere and things took a turn that shocked me. As mentioned before, any graphics are digital in the depths of my consciousness. The previous ballless, one-ball and two-ball universes appear as one or a few equations describing it, like a few fallen leaves in late autumn. But the third sphere is a dragon with the eye of "empty", and the three-sphere universe suddenly becomes complicated. The three spheres that have been given initial motion are performing complex and seemingly never-repeating movements in space. Motion, the equations that describe it, come flooding in, endlessly. I fell into sleep like this, and the three balls kept dancing in my dream, an irregular dance that would never be repeated. But deep in my consciousness, this dance is rhythmic, it just repeats the cycle for infinitely long. This fascinates me, and I want to describe part or all of this cycle.

The next day I kept thinking about the three balls dancing in the "air". My mind had never been spinning like this at full power, so much so that a monk asked the elder if there was something wrong with my spirit. No problem, the elder smiled and said: It's okay, he found Kong. Yes, I have found space. Now I can hide in the city. Even among the bustling crowd, my heart is extremely peaceful. For the first time, I enjoyed the fun of mathematics. The three-body problem (Note: The problem of how three objects with the same or similar mass move under the influence of mutual gravity is a classic problem in classical physics and is of great significance to the study of celestial body motion. , has been attracting attention since the 16th century. Swiss mathematician Euler, French mathematician Lagrange, and some scholars with the help of computer research in recent years have all found some special solutions to the three-body problem). The physical principle is very simple, it is actually a mathematical problem. At this time, I was like a dissolute man who had spent half his life looking for flowers and flowers, and suddenly felt love.

Excerpt from the three-body problem: The three-body problem has no solution

Wang Miao hesitated and took out a stack of information. This was a link to Wei Cheng’s mathematical model of the three-body problem: "I... That's why I came here. I brought a mathematical model to solve the three-body problem, which I believe is very likely to succeed." As soon as Wang Miao said this, he found that the people around him immediately started talking to him. After losing interest, everyone left him and returned to their own small circle to continue the chat. He noticed that some people were still smiling and shaking their heads when they left.

The secretary-general took the information and handed it to a tall, thin man wearing glasses next to him without even looking at it: "Out of respect for your lofty prestige, please ask my scientific advisor to take a look at it. In fact, everyone has already started to respect you. Showing this kind of respect would have been immediately ridiculed by anyone else."

The scientific advisor took the information and flipped through it: "Evolutionary algorithm? Copernicus, you are a genius, you can come up with this. People who work on algorithms are geniuses. In addition to superb mathematical abilities, they also need imagination. "

"I heard that someone has already created this mathematical model?"

"Yes, there are dozens of other mathematical models, more than half of which are much more advanced than yours, and have been created and calculated on computers. In the past two centuries, this huge amount of Calculation is the central activity of the world, and people are waiting for the results as if they were waiting for the Day of Judgment. ”

“What about the results?”

“It has been definitely proven that the three-body problem has no solution. . ”

Wang Miao looked up at the huge pendulum, which shone brightly in the morning light, reflecting everything around it as a deformed mirror, as if it were the eye of the world. In that distant era that had been separated by many civilizations, on this land, he and King Wen of Zhou once walked through the giant pendulum trees towards King Zhou's palace. In this way, history draws a long circle and returns to its original place.

"As we have accurately measured long ago, the three-body system is a chaotic system that will infinitely amplify small perturbations, and its operating rules are mathematically unpredictable in nature." said the scientific consultant .

Wang Miao felt that all his scientific knowledge and ideological system were blurred in an instant, and he was replaced by unprecedented confusion: "If even an extremely simple system like the three-body system is in unpredictable chaos, Then how can we have confidence in exploring the laws of the complex universe? "

"God is a shameless old gambler. He has abandoned us!" Einstein came over at some point, waving his violin. explain.

The Secretary-General nodded slowly: "Yes, God is a gambler, and the only hope for the Trisolaran civilization is to take a gamble.

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