In front of the screen wall, in front of the screen wall, there is a large wooden barrel soaked in cheese, and a large bucket of hot water is filled with various traditional Chinese medicines, including mushroom powder. As for the cheese himself, he was naked, and his whole body was soaked in it, with only his head exposed.

Nobita tried his best to comfort him and said, "Don't worry, little cheese, you will definitely get better, trust me!" ”

Cheese smiled dismally and said, "Boss, I believe in you. ”

But the robot from the Gluttonous Cosmic Aeolus of World No. 6 continued to introduce: "The set of cards you see is not the true appearance of the universe, but only a two-dimensional description of each universe. Because I'll talk about the four-dimensional universe later. I would like to ask you to describe to me what a four-dimensional universe is, and who can do it? ”

Everyone shook their heads, and Zhou Jinyin said: "We are people living in a three-dimensional universe, we are all three-dimensional, including robots, all objects here are three-dimensional, including our thoughts, so for the four-dimensional you said, we can't describe or imagine at all." ”

"That's why we use the description of dimensionality reduction, and the dimensionality reduction mentioned here is not really dimensionality reduction, but a description method." The robot continued, "Now back to the cards, the cards that you see, each card represents a universe, and the cylinder of these cards is the four-dimensional universe of the upper level. As for what the four-dimensional universe looks like, we don't know, we can only rely on imagination. And there are five dimensions, six dimensions, and even higher unimaginable dimensions above the four-dimensional universe.

"In this cylindrical card, our ancestors discovered a huge secret, that is, there are four unrelated and distant cards that have some kind of connection, and after years of research, this connection has been found, that is, these four cards constitute a strange formation, that is, the teleportation array.

"As long as you build a portal in each universe, you can travel freely in these four universes."

Nobita raised his hand and said, "Mr. Robot, I want to ask you a question. ”

"Tell me."

"According to you, the portals distributed in these four universes are the gates between the universes? How was the portal built in the first place? Because I know that any two of these four universes are unimaginably far apart, and you can't reach either side without a portal. Am I right? ”

"You're absolutely right. The distance between any two universes is so great that even if you use the speed of light, you will not be able to reach each other even if the universe is destroyed. The robot said, pulling out one of the cards in the bucket and putting it aside, and a little more, the card turned into a ball, and it pulled out a number of cards, turning them into spheres one after another, "Okay, let's restore the three-dimensional description of these universes, these spheres are the true shape of each universe, and each sphere is a universe ......"

"Bubble Universe!" Nobita blurted out because he had once come up with a conjecture about the bubble universe like the Archon.

"Bubble Universe?" The robot asked, "That's a nice name, but it's more complicated than the bubble universe you talked about, because it's a four-dimensional universe involved." The universe in each sphere does not simply exist in a single super-universe, but in a four-dimensional universe. Specifically, it's complicated, you just need to know that the spheres represent each individual universe.

"According to you earthlings, each sphere has a diameter of trillions of light-years, is this number unimaginable? And the distance between each two adjacent universes is hundreds of millions of times that of this diameter. Moreover, they are not necessarily in the same three-dimensional universe. ”

According to the robot, the diameter of one universe is one trillion light-years, and the distance between two adjacent universes is one trillion light-years! The universe is too vast to imagine!

"This is the real universe," the robot said, putting all these bubble universes back into the card cylinder, and continued, "So our civilization designed this card theory in order for people to understand this multidimensional and multiverse view, just to make it easier for people to understand.

"So can you understand everything I'm saying?"

Everyone nodded in confusion, and Nobita said, "I can understand, but I still can't understand how you traveled through the universe before building the portal." ”

The robot said: "According to this theory of the universe, it is indeed impossible to travel before teleportation, and the distance of trillions of light years cannot be crossed at all!" Therefore, after our ancestors put forward the theory of teleportation array, we could not imagine this problem for a long time. However, since there is a teleportation array theory, although people realize that it is almost impossible to implement the teleportation array theory, it can be said that there is no need to build it at all.

"Since there is this theory, there are still people who want to try it, so after many years of silence, someone finally made the first portal. There are twelve cosmic runes on this portal. In the process of continuous improvement of the teleportation array theory, the four cosmic teleportation arrays gradually rose to 12 universes. That's why there are 12 runes on the portal you see, including its own universe on the base. ”

"However, we saw three portals, and there were more than just 12 runes." Nobita asked again.

"Because there are dozens or hundreds of portals in each universe, and each door has a rune, there are actually more than four hundred runes, that is, there are more than four hundred doors." The bot answers.

Nobita asked again, "But why are the runes of World No. 6, that is, your gluttonous universe, the same?" ”

"It's not the same, it's all a little different, it's just not deliberately labeled," the robot replied, "You see they're the same, and that's because in our world, all the portals are in one place." The engineer is just involved in this for the sake of mystery. ”

Hearing the robot say this, Nobita said: "According to what you mean, there are only 12 universes teleported in total?" So, there's our way home on every door? It's just that you weren't in the same place when you went back? ”

"You're half right," said the robot, "it's true that there are runes on every door that you can go home, but not 12 universes, but only four." ”

"Didn't you just say 12?"

"It's 12, but eight of them have never been online. It was never on the line from the beginning. ”

"What do you mean? I didn't get it. Nobita asked with doubts.

(End of chapter)