Xin Zhai

The university life at University A can definitely be described as colorful.There are various colorful posters hanging on the notice board every day.Community activities, sports and art competitions, public welfare presentations, and interest lectures are overwhelming every day.Everyone can find something of interest here.Ye Li thinks that his qualifications are mediocre, and that his hobbies are also lackluster."Stupid" events like long-distance running, which are not technically skilled, require a lot of practice, and rely on willpower, are the most suitable for him.At first he felt comfortable all over after running sweating, and gradually he also liked the running process. While running, he emptied his mind. Running 10k and 15k seemed to take a long time, but for busy people For Ye Li, it was also a rare leisure time.

Since joining the horse association, he has also met many people, and he will take the initiative to discuss training methods with others.In addition, he is the class monitor and needs to communicate with his classmates frequently. He is much more cheerful than when he first started school.

He slept all morning on Sunday, and went to the laboratory after lunch.The circuit board of the project has been sent to the manufacturer to do it. In the afternoon, he wants to take a good look at the quantum mechanics part of the big thing.This big object class is originally a foundation of physics, and every branch in the textbook is covered, but they are not in-depth.Who knows that this old Wei is extremely demanding, and the questions of each sub-branch are quite flexible.Especially the quantum part, which is inherently abstract, made Ye Li confused.So he borrowed all of Su Xiaoqian's previous homework, and prepared to look at his own one by one.

Although Su Xiaoqian has a bad temper, he has no reservations and answers all questions.And when discussing the problem, you can find that he speaks clearly and has a solid foundation. He can talk about the key points of the problem every time, and can use different methods to get the final result.During these four months, Su Xiaoqian won the first prize in the Sudoku competition, entered the finals of the provincial model design competition, and even won the second prize in a short science fiction competition.Ye Li saw that he memorized all kinds of books from the library every now and then, and he could read, understand and absorb them at a very fast speed.Later, he didn't think it was enough, so he took over Pu Liang's library card.Such a smart mind has a weird personality, and he can often be heard arguing with others in the dormitory.Apart from Ye Li and Pu Liang, he doesn't have any good friends, but he just doesn't care.

It was very quiet in the department hall on Sunday, and there was only one janitor in the reception room, Sister Guo, staring at the computer and laughing, seeing Ye Li coming, she waved to him: "Come over today?"

In the past few months, the gatekeepers, cleaners, and several teachers who often come to see Tong Yan in the department all know him.Ye Li is enthusiastic, often helping everyone with small jobs, and gradually getting acquainted with the people around him.

"The dormitory is too messy, it's clean here." Ye Li trotted up the fourth floor with his schoolbag on his back.

The corridor was a bit dark, only a light came from Tong Yan's room.Ye Li has already figured out the routine of Tong Yan's life. Unless it's a business trip or very occasional circumstances, he is almost in the office from eight to nine in the morning.

"Teacher Tong." Ye Li greeted him.

"Yeah." Tong Yan dealt with a few emails, and when he got up to fetch water, he discovered that there was another pot of pothos and a pot of green plants that he couldn't name. They were quite common species, but he didn't know the name.He has never been in the mood for these flowers and plants, but if someone raises them for him, he can just look at them, and that would be good.

This student has now learned to discuss issues with the manufacturer on his own, but the email is copied to him, and he reads the email when he is free, and ignores it when he is not free.Later, Ye Li would help him write down those boring meeting notices in the mailbox, and write the arrangement clearly on the grid of the calendar.

After his brief run-in with the student, he relented.Because he thinks it's good to have a secretary.

"What have you been discussing with the manufacturer recently? Is there a problem with the pins of the chip?" Seeing Ye Li approaching, Tong Yan walked to the opposite side with a water glass.

"Well, his pins should be symmetrical, right? I feel that there is something wrong with the markings of 45-50."

Tong Yan has been busy with the robotic arm project recently, reaching the testing stage, but the response time of the system as a whole is too long. He has been checking the system with two students for the past few days, and has no time to care about Ye Li's affairs.

"If there is a problem, the board has to be redone."

"Yes, do you want them to pause first, and then we can confirm it here?"

"Just watch and do it."

"Oh." Ye Li put away his schoolbag and turned on the computer, "I don't have time to read programming recently. I want to read big things, and recently I learned the chapter on quantum, and I've learned everything."

"Did you? Why did you get caught?" Tong Yan wanted to laugh, but now he realized that this student was really stupid sometimes.He picked up the paper on his desk and looked at it: "This is... the Schrödinger equation?"

"Yes, but I don't know how to use it."

Tong Yan stared at the question.Ye Li said: "Substitute into the potential energy distribution equation of an infinitely deep potential well, but I don't know how to get this result."

Tong Yan picked up his textbook, read the Schrödinger equation twice, and asked, "How is this an infinite deep potential well?"

"This is an infinitely deep potential well."

"why?"

Ye Li himself was also dazed, and said "Su Xiaoqian said it".

Tong Yan quit after hearing this: "What did Su Xiaoqian say? You asked him to explain it clearly to you? This is an ordinary one-dimensional model."

"You don't know, there are some things that are not covered in the textbooks, but you can come up with questions, so you have to learn by yourself." Ye Li guessed that he was not very familiar with old Wei's methods, and had almost forgotten about quantum physics.It is impossible to solve it by reading textbooks in a short time.

"Why don't I know, you think I've never been a student of Old Wei?" Tong Yan raised his voice.

"No, it's really done. It's this last step that I don't know how to get out of."

Tong Yan gave him a pen: "Then tell me about the past."

Ye Li told him everything he knew while writing, and Tong Yan replied with a half-knowledge. The two discussed it for a long time, and they were a little emotional at the end, but they didn't say anything about it in the end.

"I'll go back to ask Su Xiaoqian at night, and I'll tell you tomorrow." Ye Li swore.

"Okay, I'll wait." Tong Yan stood up and walked out, then stopped and said, "Su Xiaoqian is right? You have to have a brain yourself, otherwise he can do whatever he says."

Ye Li has been with him for a long time, and he is no longer afraid of him, and now he is very upset, and said: "Why am I so brainless?" After thinking about it, he added: "He is generally right."

"Hey." Tong Yan looked at this student who was about the same height as him, and felt like slapping him, glared, turned and went out.

When he returned to the dormitory that night, the first thing Ye Li did was to ask Su Xiaoqian this question.Su Xiaoqian picked up the homework, looked at it, and said, "Oh, this question. This question should be a missing one, and a precondition should be added: in an infinite deep potential well."

"What?" Ye Li shouted, "Why did you write a leak? How can you be sure that it is an infinite deep potential well?"

"What are you in a hurry for?" Su Xiaoqian had never seen him like this before, and explained, "Because it is not an infinitely deep potential well, this question cannot be solved. The conditions given later are typical infinitely deep potential well conditions."

"Why? Did you ask Old Wei?"

"No, I have read several editions of quantum physics textbooks. With that condition, it is considered a typical example problem. Without that condition, there is no solution to this problem."

Ye Li has the intention to kill people now, and he doesn't know how to explain to Tong Yan tomorrow.He directly said that this question was wrong, and he felt very humiliated.Tong Yan definitely scolded him for not being able to think for himself, Su Xiaoqian believed everything he wrote.After all, my knowledge is still not solid, and I am confused when giving speeches to Tong. If it were Su Xiaoqian, he could start with the derivation of the Schrödinger equation to convince Tong Yan on the spot.

On the way to the Department Hall the next day, Ye Li made a plan to try to avoid going to Tong Yan's house for the next two days. After a few days, he would forget about it and he would be fine.Then he remembered the note he had written when he was clearing the children's table that day, there was a meeting at 10 o'clock this morning, and then he had a third-year class in the afternoon, maybe he might not be able to meet him that day.

He went up to the fourth floor and tiptoed into the room. He didn't expect to see Tong Yan and Lin Li sitting in the room talking.

"Teacher Tong, just think about it."

Tong Yan glanced at him, and continued: "The leader has told me that I have already set a quota for next year, so I will only bring one. Those who need to be recruited by the central government will not be accepted by the graduate school in the department."

Lin Li was in a hurry: "You're not right, you don't want students from this department, you want students from other schools, don't you want to turn your elbows away? Besides, my GPA is not bad, it's not TOP, and the top 20 in the department is no problem."

Seeing that Tong Yan didn't speak, Lin Li said again: "If you don't take me with you, I won't be able to graduate, really."

"Here's another trick. Why can't I just study? You can consider other teachers, or other departments, or you can go to other schools if you fail. It's too late now."

"I don't want to go anywhere else." Before Lin Li could finish speaking, Tong Yan interrupted her.

"Okay, you can think about it again and talk about it later."

When Ye Li entered the room, he felt that the atmosphere was not right. He turned on the computer and began to read the courseware, without daring to say a word.

Tong Yan stood up, and when he walked behind him, he said, "Come here."

Ye Li raised his head and saw that he was indeed talking to him, so he stood up bravely and walked towards the opposite side.

After entering the room, Tong Yan sat down on a chair, put one leg on the knee of the other, and stared at Ye Li.

"Did you understand yesterday's question?"

Ye Li smiled: "I asked."

"How to say?"

"He said that the title was incomplete, and the prerequisites for infinite deep potential wells should be added."

"Make up the conditions?" Tong Yan frowned.

Ye Li gave a "hmm" and said, "Otherwise, this question can't be done."

When Tong Yan heard this, he said incredulously, "You, what's the matter with just asking superficially? If I hadn't asked, I don't think you would have found out that there is a problem at all."

"You can't rely on others, can Su Xiaoqian help you take the exam? You have to use your own brain, you know?"

Ye Li whispered "I know".

"Learning. I think you are fooled."

Tong Yan caught Ye Li's handle, criticized him bitterly, and finally felt relieved, saying "Go".

Just as Ye Li walked to the door, he turned around and said cautiously, "Teacher Tong?"

"Ok?"

"There is a meeting at ten o'clock today, do you know?"

Sure enough, Tong Yan asked, "What happened?"

Ye Li pointed to the notice posted on his computer.There was a line written on it: "Ten o'clock in the morning on Monday is the exam week preparation meeting." He immediately glanced at his watch, it was ten o'clock.

Tong Yan took the notebook and pen on the table, said to Ye Li, "Go and read your book", and strode away.