It's a weird place, Neil has never been here, but he vaguely feels like he's seen it somewhere. At this moment, he and Siqimo stood in a courtyard of cyan brick and stone, quite large, surrounded by tall pine and cypress trees, arranged in an irregular arrangement, presumably planted by hand.

In the middle of the courtyard there is a murmuring pond, in the center of the pond stands a large rockery full of holes, behind the rockery, it seems to be a palace made of red wood, the roof of the palace is covered with black tiles, the tiles are exaggerated at the eaves of the roof high up, and on the rafters at the end of the ridge, there are several crouching monster dragons with fierce faces and other strange small animals carved on the rafters.

In the middle of the palace, above the wooden door on the opposite side, hung a huge black wooden board, on which were written in golden paint three Chinese characters the size of three human heads, and even more amazingly, Neil also heard a faint sound of footsteps outside the courtyard, while several people seemed to be talking loudly in Chinese.

Neil was so curious that he didn't even think about finding a place to hide, and just looked around excitedly.

Meanwhile, Neil's side of Schimer has been calmly adjusting the phenotyping machine on his wrist.

Footsteps and conversations outside the courtyard were heard from far and near, someone was laughing, and Neil heard the sound of a metal knocker banging on the wooden door.

Just as the courtyard door was about to be pushed open, a vortex of air appeared in front of Schimer and Neil again, and Schimer grabbed Neil and got into it again.

Upon entering the tunnel, Neil asks Schimer where they were just now. Schimer said to him: "The place where we appeared just now is Henan Province of China on Earth, and the place where we are standing is the residence of one of the emperors of their Song Dynasty. Neil's mouth was wide open, speechless in surprise.

Schimo looked at Neil who was looking stupid behind the transparent mask and couldn't help laughing: "Don't be so surprised, Neil, isn't this more magical than time travel itself?" This was just a stopover in our journey, because our destination was not 969 A.D. on Earth. Schimer paused, then continued, "As I said earlier, wormhole travel has its limits, at least for now. With our current technology, we can only create wormholes with a time span of less than 1000 years, and if we want to achieve longer distance time travel, we must rely on continuous wormhole relay to achieve it. Our brief stay on another plane is roughly equivalent to a turning point in your human journey. We'll be stopping at some points in time like 31 BC and 1031 BC, until I take you back to the time when the Zorgins came to Earth in history, and our journey will come to an end. When Schimer talks about these things, it's as simple as going to a café across the street on a weekend afternoon, but it sounds dreamy to Neil.

Schimer continued: "Neil, have you noticed that in the time travel scene I just described to you, there is a very important factor, that is, there must be an observer in the travel, and the observer must also understand the meaning of travel, which can also be understood by extension that time travel can only happen to organisms with consciousness and higher thinking, if a low-intelligence creature has traveled through time and space, but does not have the concept of time in its mind, then for it, Time travel didn't actually happen.

"Before the realization of time travel, the world we can control is three-dimensional, the three dimensions of length, width, and height, and we can move between them at will, but for the dimensional line of time, you and I can only perceive it through some signals such as the increase of memory and the aging of the body, but we cannot really touch it, in other words, we can only feel its projection in the three-dimensional space world, and cannot trace it back to itself and wander along it at will. It's like you're in a big river with no one in the middle of a rough river, and you can only follow its inherent speed, not swim against it or go faster than it. But if you get on a steamer at the moment, or if you take a shortcut from the shore and run in front of it when the river is turning, it is equivalent to us moving super fast in three-dimensional space, or passing back and forth between different spaces with the help of wormholes, and then the dimensional line of time can be controlled, and the range of movement you can move will change from three-dimensional space to four-dimensional space. In the dimension of time, there are also different scales, just as a line segment can be cut into kilometers, meters, or decimeters, millimeters, and meters, so time can also be divided into adults, days, hours, and minutes, both of which can be subdivided indefinitely, depending on what kind of precision the divider needs at that time. The time travel system that we are currently building has different precisions, and we usually set it to years or months, and then it will require more resource-intensive calculations. Once we have set a point in time that we want to reach, we can teleport ourselves to that point through the time travel system, forward or backward, past or future. The watch I have in my hand is actually a coordinate setting and signal transmitter, which can set and send the four-dimensional coordinates of the beginning and end of your trip, the coordinates of space can only be set in the inner solar system, and the time coordinates are basically unlimited. After this set of coordinates is sent, it will be transmitted to the space-time positioning base station set up on the moon, and the base station will get your data and create wormholes of different spans near the Ophiuchus black hole with different bends, and the two ends of the wormhole just connect your start and end points, through which you can beat the time. That's roughly how we implement time travel. Neil felt that he couldn't fully understand what Schimer was saying, but it was really an enviable thing that the Drogin people on the moon could already achieve time travel so easily, and he wondered when mankind would reach such a level of technology, and that there would be a lot of wonderful encounters.

He curiously asked Schiller if he had ever visited his past or future self. "I've visited my former self more than once, and I've been on every tick in the dimension of time, sometimes eating, sometimes sleeping, and of course doing all sorts of other things, like three-dimensional slices in the chrysalis of time. I have also tried to visit my future self, but every time I visit, I will see different results, and each time it is not a very certain state, and I can't tell which is the real future me. However, it is not surprising that the scenes in the long river of time are originally illusory and unreal, and those various scenes are actually just a mirror. ”

"Why do you say that?" Neil didn't understand how he could say that. Schimer sighed and said, "Neil, after all that, you may still not understand the nature of time travel. As I said earlier, the projection of light refracted forms time in the eyes of intelligent beings, and you win the race against light, thus winning a ticket to time travel. But what you might not have imagined is that the world we reach through time travel is, in the end, nothing more than an afterimage of the past and future left by light. This is like a camera, it records the world in its eyes through the lens on the negative to form memories, if the camera also has advanced intelligence, then these photos are what the world looks like in its eyes, and this photo series is equivalent to its life. In fact, for intelligent beings like you and me, the same is probably true, what we are more advanced than the camera is nothing more than superimposing some other senses such as touch and smell in addition to vision, and integrating them into the brain for analysis. Strictly speaking, the world to which time travel is not the original world, but only another world, or several worlds, that God has specially prepared for time travelers, and those worlds are superimposed on the real world. There, you can indeed truly perceive it through your eyes, ears, mouth, nose, hands and other organs, and you can also record all this completely through your brain, but what you experience and record is in essence just an afterimage that contains images, sounds, tastes, touches and other elements superimposed, and its essence is actually an illusion. In the same way, your visit is an illusion for the intelligent beings of the plane you are visiting, and as soon as you try to make any changes to the world you have reached through time travel, it will immediately trigger another parallel outcome, and at this moment, the world you are visiting has nothing to do with what it was meant to be. These truths, summed up in one sentence, are that time travel cannot change history. Just imagine, you can't travel to the past to kill yourself, and you've never met anyone from the future. Just as I had traveled to the planet Drow in the past, I could not stop the Chabis from encroaching on our homeland, but could only watch the tragic scene unfold again and again. If I were able to save the Dzorkins at that time, they would immediately go to another branch of the parallel world, but they would have nothing to do with you and me today. Therefore, in time travel, we are only spectators next to the stage, and we can't go on stage to participate in the performance in person, if we really want to change history, we must use other means, which is also the other end of the technology that we Zolkin people have been exploring. Neil had been listening to Schimer in a daze, but the tall man suddenly seemed a little sad, and then fell silent.

The two men in the wormhole fell silent again, and in place of Schimer's deep voice, only the crackling of electricity from the inner wall of the pipe echoed more and more clearly in Neil's ears.