When You Jian frightened around the fierce big dog, entered the spacious living room of Professor Yi's house, and sat on the luxurious European-style sofa, he realized that Professor Yi was not waiting for him, but for his granddaughter Yiyi.

Professor Yi lost his wife at an early age, and his only daughter also studied in the UK and settled down, marrying a British classmate. So his granddaughter is of mixed race and her nationality is also British. Yi Yi is the Chinese name given to her by Professor Yi, in fact, of course, people still have English names, and You Jian did not remember them. Of course, with his level of English, hearing is not much different from not hearing.

Since childhood, Professor Yi has only met Yiyi a few times. Now Iyi is twenty years old and is studying at Cambridge University. This time, as a student representative of Cambridge, Yi Yi attended the International University Debate in China, and took the opportunity to visit his grandfather, and Professor Yi was naturally very happy. Today is the day Yi Yi arrived, Professor Yi was sitting at home waiting for his granddaughter, but he didn't expect to wait for You Jian, a living treasure, first.

You Jian patiently listened to Professor Yi's self-absorbed gushing, thinking to himself that I am here to ask your old man to raise his noble hand, as for your granddaughter or your grandmother, whether she is British or alien, I am not interested. Taking advantage of the gap between Professor Yi's throat and picking up the teacup to drink water, he hurriedly interjected with a shy face: "Professor Yi, I didn't expect me to come by coincidence, today your ancestors and grandchildren are reunited, and I can't congratulate a poor student, so let's talk about this little fruit to show my heart." You see... Yesterday's class, it was indeed my fault, since you have such a big happy event today, forgive me once, don't let me retake it, next time I promise not to sleep..."

Professor Yi's interest was indeed good, and he laughed and said, "You kid really think I won't let you take the exam?" Tell you that the school has rules and regulations that everyone has to follow. I can let you if you fail the exam, but I don't let you take the exam, I don't have the right to do so. I just want to scare you and make you correct your attitude towards learning. Young man, it's not good to sleep all the time, this great time can't be wasted. Don't you hear the ancient poems: Don't be idle, the young man's head is white, empty and sad! ”

You Jian's hanging heart finally fell into his stomach, and he said in his heart, you are Professor Yi, it doesn't matter if you are scared, look at my toss, I almost knelt down and called you grandpa. After thinking about it, I came here, so I just asked the old man to take care of it once and for all, and I passed this elective course successfully.

Thinking of this, You Jian was just about to open his mouth, but Professor Yi seemed to see through his thoughts, and said with a smile: "With your learning attitude, it is difficult to get credits smoothly!" ”

You Jian was excited, thinking to himself, don't give me eye medicine anymore, and before he could say anything good, Professor Yi's mobile phone rang, and it seemed that it meant a text message. Professor Yi picked up his phone and glanced at it, stood up and said to You Jian, "That's it, I'll give you a chance." I guess you didn't listen well to the previous course, I have a video disc of the lecture here, you can make up for me here, and show me the door for a while. Yilai texted that the flight was delayed and had to arrive more than two hours late. She came to this wilderness so late as a girl, I don't worry, I'm going to pick her up at the airport. As for you, just sit here and study hard, and when we come back, you can go again, hehehehe. ”

You Jian secretly complained in his heart: Your granddaughter is a human, so I am not a human?! She still has you to pick it up by car, how can I go back to that point! However, he didn't dare to show a trace of reluctance on his face, so he had to babble repeatedly.

It wasn't until he watched Professor Yi walk out of the room and start the Bentley to leave that You Jian let out a sigh and lay down on the sofa with a big grin. Ben wanted to sneak away, but after looking at the big dog in the yard, he consciously gave up the idea.

After sitting bored for a while, You Jian had a whim, wanting to take advantage of Professor Yi's absence to visit this mansion and open his eyes. But after thinking about it, this old man is so shrewd, if he puts a camera in some corner, and when I look back, I dare to mess around in his house, I will be completely finished. Forget it, let's watch TV honestly.

You Jian turned on the TV and wanted to watch a TV show to kill time. I didn't expect to look at Professor Yi's magnificent decoration,This TV is also a high-end product with a 60-inch large screen,But it is not wired,Except for a set of CCTV,I can't receive any programs。 This will be a news broadcast, You Jianxin said What is there to see here, it is nothing more than the old three every day: the leader is very busy, the people of the whole country are very happy, and foreign countries are very chaotic. It seems that it is better to watch the CD.

You Jian flipped through the disc box on the table, and to his disappointment, there was not a single disc of movies or TV series, all of which were Professor Yi's lecture videos, neatly arranged according to the name and order of the course. You Jian thought to himself that this old man was narcissistic enough, he hadn't talked enough at school, and he had to put it on himself at home, it seemed that the realm of this high-level intellectual was not much better than those vulgar singers and movie stars.

It's idle to be idle, let's watch the course video of quantum mechanics, in case the old man comes back to check on the spot, he can cope with two sentences. Thinking like this, You Jian pulled out the disk labeled "Undergraduate Quantum Mechanics Elective" and stuffed it into the DVD player.

After a short while, Professor Yi's familiar figure appeared on TV. Professor Yi is younger than he is now, and it seems that this video may have been recorded several years ago.

You Jian leaned on the sofa, listening in and out of his left ear, but he didn't realize that sleepiness hit again. Within a few minutes, the thing fell asleep again. If Professor Yi on the TV screen saw You Jian's virtue, he would have to learn Sadako to crawl out of the TV and strangle him to death.

However, Professor Yi is not Sadako after all, and he still talks eloquently in the picture, completely ignoring the fact that his explanation is almost a wonderful lullaby for You Jian: "Wormhole, first proposed by Einstein. He believed that space-time in the universe could be uneven, and that if a star collapsed into a black hole, then space-time would be perpendicular to the original space-time in the Schwarzschild radius, the event horizon. In the uneven space-time of the universe, this structure means that the part within the event horizon of the black hole will combine with another part of the universe and create a hole there. This curved horizon is a specific kind of wormhole.

"Since then, many scientists have been very interested in wormholes. We know that black holes devour everything that enters his gravitational field all the time, so where do these things go? There are only two possibilities, one is to gather inside the black hole, and the other is to release these things through some channel. While black holes are usually small in diameter, can they hold an infinite amount of matter?

"If not, then the latter is the only possibility. However, it is clear that this material is not being released around the black hole again. Perhaps, then, there is a special hole in the black hole that connects to another part of space-time. This particular hole is called a wormhole.

Other scientists have put forward even more interesting hypotheses. What we call space-time is actually the universe. The ancient Chinese definition of the universe actually means this: 'The four directions are called the universe, and the universe is called the universe throughout the ages'. So, is there only one universe, that is, space-time?

"Is there another article you're reading that is exactly the same as this one? That guy isn't you, but lives on a planet called 'Earth' with mist-shrouded mountains, endless fields, noisy cities, and seven other planets revolving around a star? His or her life experience is the same as yours every second. However, maybe he or she is about to put down the article at the moment, and you are going to read it.

"The idea of a 'doppelganger' sounds strange and implausible, and is a corollary of Everett's origins in his doctoral dissertation, published in 1957. He argues that there may well be other universes outside of our universe, and that these universes are a reaction to the possible states of the universe, and that these universes may or may not have the same fundamental physical constants as we know them. And the bridge that connects these universes is also a wormhole.

"If we think that time travel can be done through wormholes, then there are two different inferences. One thinks that we can only be spectators of time, just like watching movies, and cannot change the established development of time and space. The other is that when we start time traveling, we open a new universe, or an unknown parallel world, in which we are no longer us, but a part of that parallel world. There, things will develop according to the laws there. In other words, 'our' history could be changed. ”

Of course, even if there were wormholes, the journey would certainly not be very pleasant for time travelers. The powerful radiation that runs through the wormhole will tear him apart, scorch it, and finally shoot it out as elementary particles. ”

… With such a profound theory, You Jian didn't even hear a whole sentence, he was already too empty. In the dream, You Jian seemed to have turned into a big worm that was white and fat, constantly wriggling, and even he felt disgusting, drilling from one end of the universe to another, drilling the universe into a thousand holes. As for why he is drilling around, You Jian doesn't know, it seems... Looking for a female bug?

Of course, You Jian, who was dreaming of Zhou Gong, didn't know, but at some point, an unfamiliar figure was already quietly standing behind him. In his hand, he held a glittering Swiss Army knife.