Chapter 163 You, a math major, don't know anything about this material The Jiangzhou University Materials Chemistry Team began to have serious disagreements. Everyone held their own opinions and had different views on the mathematical structure. Some said that these theorems were better combined to reduce the electromagnetic resistance effect of FeSn2 single crystals. Some took into account the phenomenon of sdH oscillation effect. After calculation, the numerical values obtained were very different. No one was convinced by the other and everyone always felt that others were wrong. If there was no consensus on this issue, the experiment could not be carried out at all. We can't all make our own models and then see who is more reasonable, right? We don't have so much material, so much funding, and even less money! If Jiangzhou's materials chemistry department cannot keep up with the requirements of the Academy of Sciences, it will be embarrassing and may even be withdrawn from the cooperation project. Everyone stared at each other, and finally someone said, "Why don't we ask Lu Shan to help?" "agree!" "I agree! Once you have built the basic theoretical logic, don't bother looking for him again." "agree!" "agree!" Just like that, Lu Shan got his first specific research content, which was to calculate and build relevant models of surface relaxation. The significance of this was to supplement the specific system energy according to actual conditions. Because the force conditions of surface atoms were different from those of the atoms in the body, the surface atomic layer moved up and down relative to the atomic layer in the body to reduce the energy of the system.
If the energy is controlled well, the atoms can be made active within the appropriate range, enhancing the performance of the material. As soon as Lu Shan saw the questions these people raised, he understood where the group was going, and he just smiled and said nothing. The doctoral member who came to find Lu Shan blushed and almost lost face. He thought that next time he must let other people come to find Lu Shan, and this person only needs to be lost once. Soon, Lu Shan took out the relevant data. His speed made all the team members look at him in awe. It turned out that Lu Shan was really good at counting! How was it done in such a short time? He couldn't help but think too much, he just took the data and ran away, and the thank you seemed very perfunctory. "People!" Lu Shan shook his head. How could he not understand what these people were thinking. Facts have proved that it is useless to give opportunities to those who are incompetent. These people go back to deduce, and then have disagreements on subsequent issues. As a last resort, they sent people to find Lu Shan. Lu Shan's research was relatively advanced, but he would not hand over the data immediately. Instead, he wanted to listen to these people's ideas and progress, so as to avoid the subsequent ideas not matching each other and he would have to spend time and energy to deal with it. But the people who came didn’t say much, they just gave specific questions and left. Lu Shan shook his head. This was equivalent to not considering the overall situation. The materials chemistry team at Jiangzhou University wanted to start from the overall situation, but they really couldn't do it. They didn't even have a clear direction. Back at the Singularity Laboratory, Poincare was somewhat indignant: "These people are so rude! They didn't even ask about our research direction! If we have any disagreements in the future, do we have to follow their ideas?" "Don't mind this matter. I'll just treat it as a way to earn points. When the time comes, I will definitely tell you my reasons. If you don't listen..." Lu Shan touched his chin. He didn't say the second half, but he already had an idea. Lu Shan is actually very interested in topological semimetals. Even if Jiangzhou University does not conduct research on this, he may request it himself. Because all computer semiconductor material technologies are currently in the hands of Westerners, and because of the Western blockade of chip technology before his rebirth, Lu Shan understands that some research must be done as early as possible. At this time, Poincare lowered his voice and said, "Let me tell you something!" Lu Shan was a little curious: "What's the matter?" "That young man Alan (Turing) is so gloomy. Can you find me another computer talent? I can tolerate him not talking all day long, but his expression is so..." Poincare did not want to say anything hurtful. In fact, he wanted to say that Turing's expression was like that of a dead person, which was so painful to look at! "Uh..." Lu Shan said that he was powerless for the time being. Each subject would not need too many experts. He could only comfort Poincare: "It's hard to find someone who is better at computers than him and is still alive. Mr. Turing's computer skills are very strong. He has understood your ideas recently and expressed them with computer logic."
Poincare curled his lips and said, "I didn't say he was incompetent, but he was... a bad person to me." After comforting Poincare for a while and handing him some specialty snacks brought in from outside, Lu Shan turned and went to Turing. Turing had a cold expression and elegantly presented the mathematical logic he had recently constructed, pointing out some problems. Then he said sternly: "Mr. Lu Shan, can you talk to Henri (Poincare) and ask him to control it?" "Control what?" "Control your snack intake. His office area is really messy. When I went there, the mood there was a bit complicated. If possible, let him lose some weight." "You know, we heroes don't need to consume food, especially junk food." Lu Shan could not feel cold, hot, or even smell anything in the Heroic Spirit Space. As for the mess in Poincare's office area, Lu Shan was no longer surprised. Snacks are easy to deal with, but how can Poincare be asked to lose weight? Lu Shan couldn't imagine that there would be such a problem between heroes. The two of them might need some time to get used to each other. After a few words of comfort, Lu Shan started the joint research. Currently, Lu Shan is perfecting the computational models and methods of surface electronic structure. The previous methods were too complicated and prone to collapse in subsequent calculations. Poincaré and Turing had serious disagreements. Poincaré suggested starting directly from the overall method of calculation and then perfecting the specific mathematical logic, while Turing insisted on doing it bit by bit, perfecting the logic step by step, and then constructing a big logic through multiple logics. The former can quickly build a system for research, while the latter is more accurate but takes too long. There is a solution, which is to use Lu Shan as a bridge, working on the big framework while working on the specific logic. For a while, Lu Shan felt really stressed. After thinking for a while, Lu Shan asked Poincare and Turing to discuss the result first, and he withdrew from the Heroic Spirit Space because Poincare and Turing had already started a "friendly" communication. Poincare was mainly responsible for output, pointing out the problems in the research. Turing was responsible for finishing off the enemy. Seeing that Poincare's emotions had almost stabilized, he gave him some fuel. He was a master of temperature control, keeping Poincare's body temperature high, and his face was flushed. Arguing is also a process of mutual learning. The two people gradually had substantive communication from pure quarreling in the beginning. This development direction is naturally what Lu Shan is happy to see. The Jiangzhou Materials Chemical Team encountered a new problem at this time, that is, the experiment was flawed, and they did not completely solve the problem with the model given by Lu Shan. If Lu Shan's work can be self-consistent, then there must be something wrong with the experiment he set up. He couldn't find the specific problem, so he had to even get the Dean of the Department of Materials Science and Engineering, Shen Yanchun, to come. As the person in charge of mathematics, Lu Shan was also able to attend the meeting to see if there was any room for improvement in his mathematical model. To prove his point, Lu Shan first explained the principle of his mathematical model: "Surface energy determines the thermodynamic stability of the surface. The lower the surface energy, the more stable the surface, and vice versa. The surface energy γ can be expressed as γ = 1/2A*(Eslab-NTiμTi-NAlμAl). where A is the surface area, the factor 1/2 indicates that there are two surfaces involved in the calculation; Eslab represents the total energy of the α2-Ti3Al(0001) surface after relaxation, and NTi and NAl represent the number of Ti and Al atoms in the surface model, respectively…" After a lot of talking, Shen Yanchun didn't find any problems, so there really was a problem with the experiment. These members all spoke out their guesses. After listening for a while, Lu Shan finally understood the progress of this group of people. It turned out that these people were still looking up information and thinking about the direction, while he had even thought about the experimental process. If he followed his model thinking, this group of people would probably really not understand. "Everyone! Can I say something?" Seeing that he was going to waste time, Lu Shan lost his patience. The meeting fell silent instantly. After thinking for a while, Shen Yanchun nodded. The other team members also wanted to see what he thought. "If we use symmetry to further restrict the continuous deformation of the system, for example, requiring the continuous deformation process to be restricted to a subspace that satisfies time inversion invariance, some individuals that were originally equivalent to each other will no longer be equivalent due to the restriction of continuous deformation. Therefore, these two-dimensional insulators with TKNN index equal to zero can be further divided into odd and even categories according to the Z2 index... For Weyl semimetals (conduction band and valence band contact at a node): by analyzing the differential structure of topological defects, it is found that the Weyl node is a monopole in momentum space, which is a three-dimensional topological defect. At these singularities, the Chern number is not well defined and a topological phase transition occurs. In Weyl semimetals, there are also two-dimensional topological defects, namely merons, whose topological charge gives the Chern number of the semimetal.
It is obvious that there is something wrong with your preparation method, which resulted in the failure to obtain the right material. If you can control it according to the model, it should not be difficult. " After he finished speaking, no one agreed or opposed for a moment, and everyone was following Lu Shan's line of thought. But the silence only lasted a dozen seconds before someone immediately objected. "I don't agree. This is a material science topic. Do you have experimental data to support it?" "Yes, have you ever done an experiment? You've only operated the lab a few times, and you got the data to support the whole grand idea?" "You are inferring materials science only from a mathematical perspective, which is a bit one-sided. Student Lu Shan may not know much about materials science." Lu Shan listened to the rebuttal but did not get angry. Instead, he looked at Shen Yanchun. Shen Yanchun was a bit embarrassed. He was obviously at a higher level, but this topic was too difficult. Even if what Lu Shan said seemed to make more sense than what others said, there was no guarantee that it was only correct in appearance. After thinking it over again and again, Shen Yanchun finally spoke: "Student Lu Shan, you should learn the knowledge of the materials first. You are welcome to ask questions at any time. Don't fall behind in math." These words seemed to be taken care of Lu Shan, but in fact they were still on the side of the team. Lu Shan did not participate in the discussion anymore. After he left, all the team members were upset. "Professor Shen, this Lu Shan is so rude! We were still discussing, why did he just leave? He thinks he knows everything just because he is good at math!" "We appreciate his cross-disciplinary efforts to help us build mathematical models, but his attitude is so ignorant!" "Can you find another math major? It's so uncomfortable to deal with him! From what he just said, I seriously doubt whether he understands materials science!" (End of this chapter)