Chapter 319 A frustrating problem (13)

Since the car was still parked at No. 2 Middle School, the couple held hands and walked towards the middle school.

"I also want!"

Yan Xiaoxi pouted and said angrily: "I want to do that tonight too."

Chen Xiaoxin was speechless, and replied bitterly: "Baby, it has been several days in a row. Even if it is a water pump, it can't be kept running for 24 hours. It must be stopped and lubricated. Metal has fatigue value!"

Speaking of which,
Chen Xiaoxin paused and explained earnestly: "Maybe you don't know what metal fatigue is. Let me give you a brief introduction. It is a process in which a material or part gradually produces local permanent cumulative damage in one or several places under cyclic stress or cyclic strain, and cracks or sudden fractures occur after a certain number of cycles."

"let me tell you."

"My husband is in critical condition right now. If you continue like this, I might have to go to the ICU." Chen Xiaoxin coughed lightly and said seriously, "I declare that the war friction between the two sides will stop from now on and enter an indefinite ceasefire. As for when the war will start, I will notify you."

Yan Xiaoxi burst out laughing, gently poked his waist, and said angrily: "If you are tired, then you are tired. Why are you talking so much? I am not unwilling to listen. You are still playing tricks in front of me, you stinky man. Okay, okay, since you want to have a good rest, then rest well and don't sit in front of the computer!"

Hearing that he could survive tonight, Chen Xiaoxin smiled innocently and said, "Actually, it's almost time. Let's go to bed early tonight."

"correct."

"The principal of our No. 2 Middle School will join the district education department in two years and serve as the deputy leader of the education department. Director Pan of the Teaching Department will be the future principal of No. 2 Middle School, and our class teacher will be the vice principal." Chen Xiaoxin said.

"The principal has finally made it. In terms of rank, it's a lateral transfer from section chief to section chief, but the power in his hands has become greater." Yan Xiaoxi held his arm, pressed her body tightly against him, and muttered, "It's a pity that the deputy leader can't do what is called "mastering everything."

"There are gains and losses."

"How is it possible to get the best of everything? Just like when I marry you, I lose all the good things from then on." Chen Xiaoxin said.

Yan Xiaoxi's face suddenly turned black, and he pinched his waist viciously, saying angrily: "I find that you really don't know how to live or die. Fine, fine. Since you said so, then don't even think about seeing the sun tomorrow morning!"

"No, no, no!"

"Hey, I was just kidding!"

Chen Xiaoxin begged awkwardly, "Why did you get so angry when I was just teasing you?"

"roll!"

"Super ugly."

Yan Xiaoxi rolled her eyes and said angrily.

Even though she was very angry with him, her body was still tightly pressed against him.

The two came to their former high school. There was still half an hour before the night self-study class. Yan Xiaoxi suddenly suggested going back later and wanted to walk around the school. Chen Xiaoxin naturally did not reject her request and accompanied her around the school.

No. 2 Middle School is not that big, and they walked around quickly. Of course, they did not hold hands with each other, after all, they had to pay attention to the impact.
“I want to go to class”

Yan Xiaoxi said softly: "Let's go see my former classmates."

"Oh"

"Let's go."

Chen Xiaoxin had no objection and silently accompanied her to Class 2 of Grade 3.

However, the two of them were originally walking side by side. Yan Xiaoxi suddenly grabbed his hand tightly and was unwilling to separate no matter what.

Faced with this inexplicable behavior, Chen Xiaoxin was stunned at first, then full of confusion, and then he suddenly realized, I said, meeting old classmates is fake, showing off is real!

Just as Chen Xiaoxin guessed, Yan Xiaoxi was naturally not going to meet her old classmates, but was taking this opportunity to show off her husband in front of her former rivals.

did you see!
Your former man is now my husband! He and I have become a couple who know each other well!
as predicted,

When the two arrived at the teaching building, Yan Xiaoxi deliberately slowed down her pace, then walked up the stairs slowly, showing off to those innocent girls.

A piece of Xu,

They came to the door of the classroom, and their simultaneous appearance caused all the students to exclaim.

However, although the two of them still looked the same as before, they no longer had the relationship they had as classmates. There was ultimately an invisible barrier between them. Yan Xiaoxi had wanted to chat and reminisce with a few of her dinner buddies, but they all looked very reserved, leaving her at a loss as to what to do. In the end, she could only chat with Gu Luo who had returned to school.

of course,

The Four Heavenly Kings are different, they still have a relationship where they can talk about anything.

The two of them didn't stay here for too long. After all, there were less than three months left before the college entrance examination, so it was almost time to go back.

“It’s very uncomfortable.”

"We used to talk about everything, but now... only Luoluo is the same as before, everyone else is... " Yan Xiaoxi sat in the passenger seat, her brows full of melancholy and bitterness.

"Sure."

"The higher you fly, the smaller you appear to others." Chen Xiaoxin said softly, "Friends are like gifts from God. One day they suddenly appear, and another day they suddenly disappear."

Yan Xiaoxi pursed her lips and didn't say much.

At this time,

Chen Xiaoxin stretched out a hand, gently grasped her jade hand, and smiled gently: "You still have me, right?"

Yan Xiaoxi rolled her eyes and said angrily: "It is because of you that I am so unfortunate."

Even so, the hands were tightly clasped together.
Three days passed by unknowingly.

Chen Xiaoxin's main task during these three days was to solve some problems in the Navier-Stokes equations. After all, he had not published an article in the field of mathematics for a long time, and it was time to shock mathematics.

The Navier-Stokes equation is a nonlinear partial differential equation that governs the motion of real viscous fluids. It is Newton's second law of fluid motion and can describe the physics of flow phenomena in many fields of science and engineering.

However, there are great limitations on its solution, especially in terms of turbulence, which is related to the initial derivation. The problem of turbulence was not taken into account, so when using this equation, it is done with approximations.

The problem that Chen Xiaoxin wants to solve is to prove that the solution to the Navier-Stokes equation exists!

For a mathematical model, no matter how complex it is, if you want it to represent the physical world, you must first have a solution that must exist. Although the NS equations provide many windows in terms of fluids, they are all approximations of the solution.

no way,
There is currently no formula that can obtain a complete solution. Although many physicists believe that approximate solutions are correct, there is still a lack of a formal proof in mathematics that these solutions do exist.

In fact, simply proving whether this solution exists is not enough to perfectly solve the NS equations, because there is also a second question: whether these solutions have boundaries.

In other words, does the solution of the equation have a singularity? This question is more important than the previous one. If there is such an uncalculated infinite value in the NS equation, then the NS equation will be invalid. It also directly shows that humans have missed some particularly important and unknowable physical content.

"so hard!"

Chen Xiaoxin felt like his scalp was about to split. He calculated for a long time but still had no clue. It was like he was standing on an isolated island, surrounded by endless ocean, and had no idea where to go.

Currently,

Chen Xiaoxin thought of several ways. The first one was to use power series expansion in the function space. This method was very effective in constructing local solutions with large initial values ​​or global solutions with small initial values. Unfortunately, the global solution with large initial values ​​still could not be completed.

The second method is more abstract, using some subtle features of the NS equations to explore them step by step. Unfortunately, this seemingly outrageous method is ultimately limited to subcritical situations.

It's cold
Cool thoroughly.

Chen Xiaoxin didn't know whether he should continue or not. During these three days, he slacked off in the morning and worked on the NS equation in the afternoon. His slacking time was getting higher and higher, but his progress on the NS equation remained unchanged. Every time he thought of a solution, he couldn't proceed in the end.

But then again
How strong is Russia's Perelman?

Chen Xiaoxin sat there quietly, like a person suffering from Alzheimer's disease, with empty eyes and silly look between his brows.

Let's sort it out first.
These factors should be needed to get a complete solution.

First, a nonlinear stability theory is needed, followed by a comparative principle argument, where the solution is controlled by another object, the solution is substituted into the original object, and finally a functional of the solution is constructed.

"Um"

"This should be!"

Chen Xiaoxin nodded and muttered to himself thoughtfully. Then the next second, he pulled his hair hard, his face full of pain and torture.

Useless!

A nonlinear stability theory. This is more difficult than a complete solution to the NS equations!

I. I simply cannot control the highly nonlinear behavior at fine scales. I. I simply do not have the ability to do so!

at the same time,

An experimental base far away in Beijing.

Academician Ma and his team are conducting the final experiment.

After many days of continuous overtime work, a new high-temperature superconducting magnet was finally developed, and it will soon be verified. The various values ​​calculated by Chen Xiaoxin in the theoretical model.

"it is good"

"Attention everyone, the experiment will begin soon."

Academician Ma, the commander-in-chief, was now speaking to all members of the team through a walkie-talkie.

For a time,

Everyone started to get nervous.

"The countdown begins!"

"ten!"

"Nine!"

"Eight!"

"."

"."

"three!"

"two!"

"one!"

"Device activated!"

(End of this chapter)