Chapter 1980: The truth of space

"Do you know the language of the Dragons?" The old man did not directly answer Jiang Fei's question.
"Understand it." Jiang Fei replied that he had not worked hard in this area before.
"That's good, I can't express it clearly in human language ..." The old man said here and switched to using the Dragon language to communicate with Jiang Fei.
Because Jiang Fei studied the language of the Dragon tribe hard for a while, the following words said by the old man can be transformed into his own language and understood.
"What do you understand about space?" The old man asked. The dragon language in his mouth was automatically translated into a vocabulary that he could easily understand.
"Space? I know we live in a three-dimensional space, maybe there are living things in a higher dimension than us." Jiang Fei said, but in his mind, it is no longer possible to have living things in higher dimensions, because that group The guy has invaded this universe!
"Yes, senior, is the fourth dimension of four-dimensional space time?" Jiang Fei suddenly thought of a question.
"Of course not!" The old man shook his head, and then said to Jiang Fei: "Time is a special vector. There is time in one-dimensional space, and time in two-dimensional space. Time exists in every dimension of space! Time And space are two different concepts! "
"That's it!" Jiang Fei nodded.
"Well, the relationship between time and space has been explained, so can you tell me the relationship between the various spatial dimensions?" The old man nodded, and then continued to ask Jiang Fei in the language of the Dragons.
"Relationship?" Jiang Fei froze. He didn't understand what the old man asked.
"Well, let me tell you from the beginning." The old man sighed, and then said to Jiang Fei: "The so-called one-dimensional space is a straight line. If there are living things on this straight line, then in its perspective, There is only one point forward and backward, and it can only move forward or backward. "
"And countless straight lines constitute a plane, which is the so-called two-dimensional space. The creatures in it are no longer limited to straight lines, but can move freely up, down, left, and right." The old man continued.
"Yeah! It's true!" Jiang Fei nodded. The old man's description coincided with his knowledge in the scientific and technological world. Although the language of the Dragon family on the spatial dimension is not the same as the outside world, it also corresponds to each other. Is a meaning.
"The three-dimensional world we live in is actually composed of countless planes. After the layers of two-dimensional worlds are superimposed together, they constitute our three-dimensional world." The old man said here and looked at Jiang Fei, and then Continued: "So you can imagine that four-dimensional space is actually formed by the superposition of countless three-dimensional spaces."
"What does the four-dimensional space look like?" Jiang Fei asked curiously.
"To talk about this, we have to talk about our perception of space." The old man said here paused, and then continued: "I don't know if you are now, our observation of the world is actually through dimension reduction. Way. "
"What do you mean?" Jiang Fei froze.
"Take an example." The old man reached out a stroke and a light appeared in the air.
"This is a straight line, which represents a one-dimensional space. If there is a creature living here, in his eyes, there is only one point in front and one point in the back, which represents the creature living in one-dimensional space. , He can only see the point. "After the old man waved, the light in mid-air disappeared, replaced by a light wall.
"You see, this is a plane, which represents a two-dimensional space." Then the old man waved his hand, and many patterns appeared on the light wall, with squares and circles.
"If it is a creature living on this plane, in his perspective, these squares or circles are actually invisible to him. All he can see is a line facing him." The old man waved his hand again after speaking. The light wall disappeared, but was replaced by a solid wall.
"We live in a three-dimensional world. Now look at it from your perspective. What's in front of you?" The old man asked Jiang Fei.
"A wall!" Jiang Fei said for granted.
"Yes! That's right! But it's also a plane! You can't see anything behind the plane at all, because you are a person in the three-dimensional world, so you can only see the plane of the two-dimensional world." Said the old man.
"No! I can see three-dimensional objects, such as this ball!" Jiang Fei said, taking a ball out of the ring space.
"Oh, that's just the answer that you supplement your brain in the subconscious based on a lot of relevant knowledge ..." The old man said that he took the ball from Jiang Fei's hands, and then he waved his hands, and the surrounding light instantly became dim. At this time, in the eyes of Jiang Fei, the ball had only a slight round shadow left.
"You see ~ EbookFREE.me ~ After losing the contrast between light and dark, your brain can no longer calculate, and the real image you see is just a circle." The old man laughed.
"That's the way ..." Jiang Fei nodded. It turned out that the three-dimensional world in his eyes was nothing more than the two-dimensional image returned by his eyes, and the brain then calculated the supplementary results based on the knowledge of light and dark contrast and near, large and small.
"So, a person in a dimensional space can only perceive the space he is in through dimensionality reduction. He cannot see the true face of the space he is in!" The old man finally concluded.
"That's it!" Jiang Fei nodded, no matter how charming the scenery in the picture, all the creatures in the two-dimensional space can only see a straight line, and the colorfulness of the three-dimensional world is not too small in people's eyes. It is a splicing of pictures. Although this answer makes Jiang Fei a bit lost, it is the case.
"So you understand." The old man smiled, and then continued: "The so-called four-dimensional space is the product of the stacking of countless three-dimensional spaces. Of course, this kind of stacking is not as simple as stacking the bricks to build a house. It is still a three-dimensional world. This kind of stacking is structured together in a way that we cannot understand. People there can see our world as we see through the essence of the two-dimensional world; the world in their eyes is truly Three-dimensional images, and because we ca n’t observe the true three-dimensional world, we ca n’t describe their world.

"Are people in our three-dimensional world unable to imagine what a four-dimensional world looks like?" Jiang Fei asked.
"No!" The old man shook his head, then said, "But I have something interesting, which may help you solve some doubts."
"What's interesting?" Jiang Fei immediately asked.