Pang Xuelin said: "Zhizi, can you observe the physical parameters of this space now?" ”

Zhizi frowned and said, "It's a bit troublesome, the space in the wormhole should belong to the five-dimensional space-time, and there is no way to observe it accurately." ”

"You mean, there's a temporal dimension within this space?"

Zhizi said: "Yes, in this space, the second law of thermodynamics is still valid, and there is no way to reverse the flow in time. ”

Pang Xuelin nodded, according to theoretical calculations, there should be a kind of wormhole that can travel through time.

But apparently, this wormhole they are in is not like that.

This is just a wormhole in the sense of four-dimensional space, an extra dimension of space, which allows spaceships and other entities to travel faster than light across the limits of space distance.

This is like having two points AB on a curved two-dimensional plane, and if you pass through the two-dimensional plane, the distance from point A to point B is one light-year.

However, if these two points are connected in a straight line through three-dimensional space, the distance between point A and point B can definitely be greatly shortened.

The wormhole where Pang Xuelin is now located is on a four-dimensional spatial scale, connecting two points in three-dimensional space.

Pang Xuelin looked at Zhizi and tried to take a step in the direction where she was.

But in the next second, he and Zhizi staggered more than ten meters in an instant, and Zhizi actually appeared behind him.

"It's kind of interesting."

Pang Xuelin laughed.

The sense of direction in three-dimensional space obviously does not apply to four-dimensional space, and the direction of Zhizi that he perceives is obviously not the real position of Zhizi.

"Tomoko, can you come to me?"

"I'm afraid not, I'm trying to perceive the fourth dimension now, but it's hard to understand how this dimension exists."

Pang Xuelin pondered for a moment and said: "Zhizi, I remember that high-dimensional objects were described in the three-dimensional world like this, in three-dimensional space-time, from a one-dimensional perspective, elementary particles are equivalent to a particle, from a two-dimensional and three-dimensional perspective, elementary particles begin to show an internal structure, from a three-dimensional perspective, elementary particles have shown a macroscopic three-dimensional structure, from a four-dimensional perspective, elementary particles are equivalent to a planet...... Elementary particles from a seven-dimensional perspective may already be as complex as the solar system in three-dimensional space; From an eight-dimensional perspective, the elementary particle is an existence as grand and vast as the Milky Way; When the perspective reaches the ninth dimension, the number and complexity of the internal structure of an elementary particle is equivalent to the entire universe ......"

"So, what would happen if you unfolded the Zhizi in a four-dimensional structure now?"

Tomoko blinked and said, "Husband, I understand!" ”

Immediately afterwards, a strange mirror geometry appeared in Pang Xuelin's eyes.

It's strange because, although still, its overall shape changes from moment to moment.

Pang Xuelin knew that this was because his eyes and brain were unable to perceive and construct the fourth dimension.

"Tomoko, can you measure some of the basic physical parameters of this space now?"

Pang Xuelin asked.

"I'll try!"

After a while, Tomoko's voice sounded again:

"Four-dimensional space vacuum speed of light: c=1.56*10^18m/s; Fine structure constant: α=1.6993*10^-15W/m^2/k^-4;Planck constant......"

Before Zhizi finished speaking, he suddenly shouted: "Husband, it's too late, we're about to get out of the four-dimensional space!" ”

In the next second, Pang Xuelin only felt that the hull of the ship shook slightly, the colorful light in his eyes instantly dissipated, and the objects in the spaceship that showed an endless sense of depth seemed to be dominated by some kind of force, and instantly returned to their original state.

Pang Xuelin slowly floated to the porthole, Saturn had disappeared, and in the distance, a giant red star was emitting a warm light.

According to the records of the shrimp civilization, this red giant star is likely to be the galaxy where they hid after escaping from their home planet, and it was here that they discovered the entrance to the wormhole leading to the solar system.

This galaxy is almost 300 light-years away from the solar system.

Pang Xuelin looked at the time again, and less than five minutes passed from the time they entered the wormhole to the time they came out.

The distance of 300 light years took less than five minutes in a four-dimensional space.

And there is no relativistic effect.

If the basic physical parameters of this world are consistent with the real world, then in the future real world, the best way for human beings to travel interstellar is to use this four-dimensional wormhole for long-distance crossing.

At this time, Tomoko floated from behind him and said, "Husband, 20 million kilometers away, there is a flying machine flying towards where we are. ”

Pang Xuelin was slightly stunned and said, "Is it a shrimp man civilization?" ”

Tomoko shook her head and said, "Probably not." ”

As he spoke, the two-dimensional screen unfolded, and a soft creature similar to a starfish appeared in front of Pang Xuelin's eyes.

Pang Xuelin frowned and said, "How is the wormhole now?" ”

Tomoko said: "Maybe we just caused interference with the wormhole, the wormhole is very unstable at present, even if our lifeboat wants to go back, it is difficult for the other party to let a large warship go to the solar system through this wormhole." ”

Pang Xuelin nodded, pondered for a moment, and said, "Then let's go too!" ”

As he spoke, he waved his hand and pulled Tomoko back into the system space.

Subsequently, Pang Xuelin said: "System, prepare to return!" ”

"Understood!"

The next moment, Pang Xuelin opened his eyes and found that he had returned to the teacher's apartment of Jiang University.

It was still dark outside, and when I looked at the time, it was half past three in the morning.

There is no systematic lottery for the task rewards in this world, and Pang Xuelin does not need to stay in the system space for a period of time.

As soon as Pang Xuelin turned his head, he saw a bottle of blue liquid on his bedside table, with four words written on the bottle: genetic medicine.

At the same time, Pang Xuelin felt that in the system interface, the worlds he had traveled through before lit up one by one, and he could choose one of the worlds to return to at any time.

Pang Xuelin thought about it, put this matter aside for a while, he wanted to try the effect of genetic medicine.

Pang Xuelin waved his hand, and Zhizi appeared in his room.

Pang Xuelin said: "Zhizi, I want to use the genetic medicine, you help me watch, if there is any problem, call 120 immediately." ”

"Understood!"

Tomoko smiled sweetly.

Pang Xuelin picked up the genetic medicine and sniffed it, then took a sip gently, which was similar to a drink.

Pang Xuelin poured it down, and in the next second, Pang Xuelin only felt that it was dark in front of him, and he fell on the bed.

When Pang Xuelin woke up again, he found that he was lying on the bed, the sheets and quilts had been changed, and Zhizi was sitting at the head of the bed.

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