Top Student

Xu You was so eager to go to Wang Xiangwu's place, not just because he was attracted by Wang Xiangwu's subject.

Indeed, during this period of time, there has been no further progress on the subject of the mechanism of high-temperature superconductors.

Because this subject is too complicated, breakthroughs in every small stage are even more difficult than solving an ordinary subject.

Xu You will also often fall into a bottleneck state, making it difficult to continue to advance this topic.

It just so happened that Wang Xiangwu had another subject, and Xu You also felt that he couldn't put all his energy on a subject that was in a state of stalemate.

Moreover, as Wang Xiangwu said before, there are similarities between condensed matter physics and quantum physics.

Xu You really felt the same way.

In the whole of physics, condensed matter physics and quantum physics are indeed two closely related branches.

Maybe, Xu You can really get some new ideas from Wang Xiangwu's laboratory.

When Xu You came to the Quantum Physics Laboratory, Zhao Weijia immediately greeted him.

"Xu You! It's only thanks to you that I can show my face on CCTV! You know, there are so many girls asking me out on a blind date recently, the queue is almost from Jida to Jinghua."

Xu You thought about it, and it seemed that there were not so many people.

"So, brother, after so many days, are you still on a blind date?"

Hearing Xu You's words, Zhao Weijia smiled awkwardly.

"A blind date is like picking fruit in an orchard. It is stipulated that you can only pick one. When you encounter a fruit that is not bad, you always think about whether you can meet a better fruit for a while. As a result, as you walk, you find that it is the same fruit as before. Even better. But when you went back to look for that fruit, you found that someone else had already picked it."

"Then is there a possibility that you don't want to pick some good fruits?"

"this……"

After the two chatted and laughed a few words, they also started to get down to business.

"Xu You, you are here today. Teacher Wang asked you to participate in our new project. Teacher Wang is not here. Let me give you a brief introduction about what this project is about."

Listening to Zhao Weijia's narration, Xu You also quickly understood the main research content of this subject.

This project mainly studies the quantum phase transition of two different lattice models.

The so-called quantum phase transition, simply put, is the change of the quantum state of matter caused by the change of some non-thermodynamic order parameters.

These order parameters include pressure, magnetic field, doping and so on.

Listening and listening, Xu You also understood what the main problem encountered in the current project is.

"So, the numerical results of the Jaynes-Cummings lattice model and the quantum phase transition of the Rabi lattice model have relatively large errors from the theory?"

Zhao Weijia also nodded when he heard the words.

"How can I say this error... It's not too big, but it's not so ideal. We also tried to use various methods to re-measure the numerical results, but we didn't get particularly satisfactory data. Teacher Wang means, It is better to further control this error."

"Let me look at the data first."

Xu You was not in a hurry to analyze the reasons, but wanted to learn more about the details of the experiment before making his own judgment.

"Okay, I'll find it for you."

In front of Xu You, Zhao Weijia's attitude is very good, as if Xu You is a professor.

Of course, in terms of knowledge and ability, Xu You is indeed about to reach the level of a professor.

Immediately, Zhao Weijia found the corresponding data in the computer.

Xu You looked carefully, and indeed felt that there seemed to be some problems in it.

These data gave Xu You a strange feeling.

Although such an error is still within an acceptable range.

But it's only on the verge of passing.

Xu You vaguely felt that such a result might be very dangerous.

It may even have an impact on key conclusions.

"Brother, let me take a look at the formula."

"Okay, wait a moment."

Then, Zhao Weijia found out the formula part in the thesis, and described the derivation process of the formula.

At this time, Xu You suddenly noticed a detail.

"Wait a minute! Brother, did you use an approximation here?"

"That's right, we have taken an approximation for the phase transition here. Theoretically speaking, the approximation here should be negligible."

Xu You also knew this way of dealing with it.

Indeed, in theory, such an approximation has very little impact on the result, so small that it can be completely ignored.

But the final error value is probably related to the approximation here.

Xu You continued to browse through the experimental process and data processing methods in the paper, and was constantly thinking about something.

Finally, after repeated viewing and thinking.

Xu You found out the problem.

"Brother, although theoretically speaking, the error of this approximation is negligible. But in fact, there is a process behind it that will amplify the error, so it will cause problems in the fitting of the numerical results."

Zhao Weijia also listened to Xu You's explanation, and re-analyzed it herself, and finally understood what Xu You said.

"So that's the case. If you didn't say it, we wouldn't have discovered this problem at all."

Because everyone is used to this approximation, subconsciously they don't think it's a problem.

"But, Xu You, if we don't do approximate processing here, then this result can't be expressed."

Because the problematic formula is theoretically a formula of infinite length.

Only through approximation can the final result be expressed.

Otherwise, no calculations can be performed at all.

"That's right, brother, I'm also thinking about this question."

At this time, Wang Xiangwu also came to the laboratory.

"Xu You, you're here."

"Well, here I come, teacher."

"Have Jia explained the problem to you?"

"Yes, brother has already explained the problem, and we just found out what caused the problem."

Hearing this, Wang Xiangwu was also surprised.

We have been discussing this issue for several days, but no specific reason has been found.

When Xu You just came to the laboratory, he found out the reason?

"What's the reason, come and tell me!"

Next, Xu You told Wang Xiangwu what he had just told Zhao Weijia.

Wang Xiangwu reacted much faster than Zhao Weijia, but it took him a while to figure out the reason.

"Sure enough, I think there is something wrong with it. Fortunately, I asked you to come here, otherwise we don't know when we will find out the reason."

At this time, everyone fell into deep thought again.