Chapter 41

The Chief of the Underworld Has Gone Mad

A post quietly appeared on the Guangling University forum, and students quickly clicked on it.

"I guessed who it was as soon as I saw the title, was it what I thought?"

Yes, it's the person you're thinking of.

"What's wrong with you?"

"What else could it be? He's been in the underworld for almost three years. It's already amazing that he's managed to hold on until now before going insane."

"OP! You can't use clickbait titles, come out and explain!"

"Actually, I'm not really sure either, but he's been acting really strange lately. He's either gone crazy or gone mad."

"For example, do you know what task the King of Hell assigned him? To read ten books, and write 100,000 words of reading notes for each book!"

"One hundred thousand! My goodness! I haven't written a single reading note since graduating high school. This is roughly equivalent to 100 high school essays!"

"They still have to write all 10 books like this, isn't that terrifying! But Yan Jiusheng actually expressed his gratitude to the King of Hell. Really, it wasn't just talk, he was genuinely moved to tears with heartfelt gratitude!"

"They really have gone mad."

"And do you know what? He's been practically fawning over his three fellow disciples lately, especially Ji Zhixing."

“I’ve seen it before. He does all the cleaning, taking out the trash, and cleaning the equipment. This is the first time I’ve seen a senior student fall to this level.”

"It wasn't like this before, there must be a reason."

The post was a heated discussion about this reason, but no one knew the truth, because Yan Anjin, Ji Zhixing, Zhao Yi, and Sun Er were not the type to spread rumors.

However, after being reminded of the post by a friend, Yan Jiusheng shared his own experience.

"I accidentally deleted more than three months' worth of data from the lab using the rm-rf command."

"Ah, this..."

"Oh My God!"

"Help! How could such a tragedy happen!"

"The King of Hell didn't kill you?!"

"They didn't even expel me from the sect! I can't swallow this insult even if I were in the King of Hell's shoes. How much money and effort did they put in all of this!"

"It seems that the King of Hell has a better temper than I thought. Did I misunderstand him in the past?"

"To tolerate such a blatant mistake and only punish him with reading notes is truly a revelation of my understanding of the King of Hell!"

Seeing these floors, Yan Jiusheng was filled with mixed emotions. He had always wanted to clear his mentor's name, but had failed several times. He never expected to achieve a little success in this way.

"Ji Zhixing and the others are really good-tempered; they can tolerate this?"

"If I had a fellow disciple like that, I would really break down!"

"They didn't even lay a hand on us? Even a group beating wouldn't quell our anger!"

Yan Jiusheng was deeply grateful for his fellow disciples' tolerance, and he typed a few words.

"Professor Yan and Ji Zhixing worked together to restore the data."

"Impossible! Unless they have time-reversal magic, how could data deleted by rm-rf be recovered!"

"Senior Brother Yan, are you hallucinating?"

"You should go to the hospital to get it checked out. Since it has already happened, don't deceive yourself anymore. Only by facing it bravely can you move forward!"

"No, they really have all been restored. Professor Yan can recall all the data, and so can Ji Zhixing. They each replicated the data and compared them one by one, and they all match."

After typing that sentence, Yan Jiusheng logged off; it was time to go to the lab.

His statement sparked a debate on the forum.

"Damn it! I don't believe it! How much data do you have over three months? How can they possibly remember it all?"

"I believe you can memorize tens of thousands or even hundreds of thousands of words, but data is just meaningless and irregular characters. How is it possible to memorize a large amount of data?"

"Well, it's not like there's no precedent. Didn't a top student memorize 100,000 random numbers on a TV show last year?"

“It’s different. That person consciously concentrated on memorizing and remembering, and such short-lived memories are quickly forgotten. But Ji Zhixing and the others probably didn’t anticipate this situation, which is to maintain the memory for more than three months in an unconscious state. Is that even possible?”

"But Yan Jiusheng has no reason to lie. He can just ask his three fellow disciples."

"Could it be... that this is actually true?"

"After witnessing Ji Zhixing take the final exam early, I learned a lesson: don't judge others by your own standards. Just because you can't do something doesn't mean others can't."

"I believe it too! What an incredible memory!"

"I've always heard that Yama is terrifying but also very powerful. Today I finally got a glimpse of his power."

"Ji Zhixing is just as good, why don't I have that kind of brain?"

"I pray to the God of Learning, and beg to pass the exam!"

This sentence seemed to be a signal, and a series of people began to worship the "god of learning" in the post.

...

Zhao Yi and Sun Er later became very interested in Ji Zhixing's methods for training memory, and Ji Zhixing gave a brief description of the first and second stages of training.

Zhao Yi thought about it and realized that since they weren't humanities majors, there was no need to go to such lengths to train their memory. Sun Er felt that her memory wasn't exceptional, but it wasn't bad either, and she was already busy enough with experiments and didn't want to distract herself. So the two of them stopped focusing on memory training.

As soon as Yan Jiusheng arrived at the lab, he started working again. Seeing that Ji Zhixing's reaction vessel had already recorded the data, he rushed to clean it.

Ji Zhixing felt a little awkward: "Senior Brother Yan, there's no need for this, really! It's all in the past."

Yan Jiusheng shook his head: "Just let me do it, that way I'll feel better."

If he hadn't been lucky enough to meet Professor Yan and Ji Zhixing, teachers and juniors with photographic memories, the grave mistake he made would have been unforgivable. Therefore, doing odd jobs actually made him feel a little better. He didn't expect to be a slave for life, but at least he had to be diligent during his time in the lab.

Unable to dissuade him, Ji Zhixing could only ask, "Senior brother, how many study notes have you written?"

He knew that Yan Jiusheng's report was submitted the next day. Professor Yan had given him a requirement of 10,000 words, but he had written nearly 20,000 words.

Ji Zhixing also read it, and every word was truly heartfelt. Yan Jiusheng genuinely felt remorse and guilt.

Professor Yan assigned him two tasks: writing a self-criticism and writing reading notes. Although the reading notes were lengthy, there was no deadline, indicating that Professor Yan was not actually blaming him.

Zhao Yi also chimed in, "Fortunately, no damage was caused, and we certainly don't blame you."

Sun Er also said, "Senior Brother Yan, Professor Yan assigned you the task of taking reading notes, certainly not to watch you do these chores. You should focus your attention on the experiments."

Yan Jiusheng naturally understood Professor Yan's deeper meaning in dealing with him, but the more tolerant his mentor and fellow students were, the more guilty he felt. At this time, Ji Zhixing also persuaded him, as did Zhao Yi and Sun Er, and he gradually cheered up.

The matter was thus resolved without serious incident.

Under Professor Yan's guidance, the laboratory research continued smoothly. After this incident, Yan Jiusheng was truly motivated to conduct experiments. He used to occasionally slack off, but now he was practically a workaholic. Coupled with the already diligent and hardworking Ji Zhixing, Zhao Yi, and Sun Er, the research atmosphere in the laboratory became increasingly vibrant, and progress was rapid.

When May arrived, the experiment achieved preliminary results; they found a material that met the requirements of Professor Yan's project. This material is a geometric gel made by combining polyboron dimethylsiloxane with another expandable foam material.

After identifying the right direction, the second stage is to further adjust the material to achieve the effect described in Professor Yan's paper—automatically adjusting the changes in softness and hardness according to external forces.

“Next, everyone will approach the materials in four different ways,” Yan Anjin reassigned the tasks.

"Yan Jiusheng, you are responsible for fine-tuning the various possible ratios of the two materials in units of 0.001..."

"Zhao Yi, you're in charge of finding a weaker but stable and controllable capping agent to control the inorganic ion reactions in the material..."

"Sun Er, try using traditional organic polymerization methods to see if you can apply them to this material. Pay attention to its superposition state..."

Ji Zhixing listened from the side and felt that the task assigned by Professor Yan was quite suitable for his personality and strengths.

Yan Jiusheng lacked a bit of quick wit, but he had a good attitude and was patient enough to complete some very trivial tasks. Fine-tuning the material ratio in units of 0.001 actually tested his patience. An impatient person might secretly move the decimal point one place to the left to cheat the experiment, but Yan Jiusheng would never cut corners like that.

Zhao Yi is calm and focused, and once he gets to work, he'll be completely absorbed. If Professor Yan assigns him to experiment and develop a suitable capping agent, he'll definitely concentrate his efforts in that direction.

Sun Er is quite lively, and can only maintain his enthusiasm for monotonous work for a short time. However, the ever-changing nature of organic polymerization allows him to maintain his long-term passion for experiments.

Ji Zhixing couldn't help but think of the 11 members of the club. For the first five club activities, he was the one who analyzed the various aspects of knowledge involved in the papers. Starting from the sixth activity, they began to use computer software to explore directions. So far, the activities have lasted for 12 weeks. Although they are still in the infancy stage, they have already found two feasible directions.

Once the activities were running smoothly, Lin Lang and Xu Dongyang led the club most of the time, and he had less contact with the 11 members, only having a vague impression of their personalities and strengths. It seems he still needs to pay more attention to this in the future, so that he can assign tasks to the right people during the actual trial phase.

While they were pondering this, Yan Anjin had already arranged the work for the three of them, and it was Ji Zhixing's turn.

"Ji Zhixing, you are in charge of studying the regularity and decay properties of the MHD equations in incompressible fluid dynamics."

Ji Zhixing immediately realized: "Is it about using the Navier-Stokes equations to intervene in the long-term behavior of the incompressible MHD equations?" He had also considered introducing the MHD equations when researching the zero-gravity seat project, so he had also read some related literature.

“Yes,” Yan Anjin nodded, “including the global existence of smooth solutions and the decay of higher-order derivatives.”

Yan Jiusheng clicked his tongue in surprise. My god, the task his mentor assigned him was on a completely different level compared to Ji Zhixing's.

His work requires minimal mental effort, but it does demand time and patience. He's very self-aware; jobs that only require physical labor are perfect for him!

Ji Zhixing's task was the complete opposite; it required little physical exertion but was extremely mentally taxing, and its depth and difficulty were sufficient for a master's thesis. However, he was confident that Ji Zhixing was capable enough to handle it.

After explaining the tasks for the second phase, Yan Anjin checked the time and said, "That's about it. Let's call it a day and go back to rest."

The four students watched their instructor leave, then tidied up the lab together before going their separate ways.

Zhao Yi and Sun Er still traveled together.

"Look." Zhao Yi nudged Sun Er with his elbow, reminding him to look to the right. "In this direction, Zhixing is going to the library, right?"

"Wow! Young people have so much energy," Sun Er said in a mature tone, tapping his back with his hands behind his back.

Zhao Yi was amused by him, but after laughing, he felt a little sad: "I feel like I've aged two years in vain. It's like I wasted those two years of schooling."

Two or three months ago, he still harbored ambitions to compete with Ji Zhixing. However, after working together for some time, he has come to realize that the two-year age difference does not prevent Ji Zhixing from quickly surpassing him through his efficient learning. Even in the laboratory, starting from the same starting line, Ji Zhixing has now far surpassed him.

He wasn't jealous, but rather felt somewhat powerless.

Sun Er patted him on the shoulder: "Don't be discouraged. He has to take care of club activities in addition to the lab every day. It's only natural that he can still find time to broaden his knowledge.

During this period, they were conducting experiments in the laboratory. Sometimes they had to wait half an hour or an hour for the reaction vessel to produce results, and they would naturally take a short break during this time.

Ji Zhixing rarely takes a break; whenever he has free time, he's either reading books or academic papers. He typically reads at least two books and seven papers a week.

Ji Zhixing seemed to never tire. To be honest, even those who watched him felt exhausted. Although they wanted to emulate him, they could only achieve half of what Ji Zhixing had accomplished.

Therefore, Zhao Yi and Sun Er were quite impressed with Ji Zhixing's rapid progress. Just like the task Professor Yan had just assigned to Ji Zhixing, they hadn't even fully grasped it before Ji Zhixing had already quickly understood the core of the topic—that was the difference.

Zhao Yi wasn't one to give up easily; he quickly rallied after a brief moment of reflection. He had his own strengths and responsibilities. Aiming to surpass Ji Zhixing's achievements each day was enough!

When Ji Zhixing arrived at the library, it was only four o'clock in the afternoon, and there weren't many people in the library. He went straight to the first shelf of the ninth row on the second floor and took out a copy of "Magnetohydrodynamics". Then he went to the twelfth shelf and reached out to take out "Ideal MHD" and "Generalized MHD Equations and Hall-MHD Equations".

Now, he knows the books on the second and third floors like the back of his hand. He probably knows which books are on which shelves better than the librarian does.

What happened a few days ago unexpectedly made him realize that his memory training had yielded excellent results, but there were also shortcomings.

Both Professor Yan and Professor Yan reviewed data from over three months ago, but Professor Yan was relaxed and at ease after completion, while Professor Yan was in a much worse state.

Professor Yan said that he was the same way when he was young. He learned and absorbed too much in a short period of time, and thought too much, so this was inevitable. However, the solution is easy; just like physical fitness, more exercise will do the trick.

So Ji Zhixing has been consciously training his brainpower during this period, and his first target is the library.

Guangling University Library has a total area of ​​28,000 square meters and a collection of 6.2 million physical books, distributed across tens of thousands of bookshelves on six floors.

Ji Zhixing's way of exercising his brain is to memorize the name of every book on each bookshelf and its location. After memorizing one bookshelf, he closes his eyes and recalls it, making sure he doesn't miss any before moving on to the next bookshelf. Then, before going to sleep at night and after waking up in the morning, he goes through all the book information he has recorded in his mind.

Since most of the science and engineering books were concentrated on the second and third floors, Ji Zhixing started from those two floors.

He has been training like this for a week. On the first day, he could only do it slowly, one bookshelf at a time. On the second day, he memorized an entire row of bookshelves at once.

Within a week, he had memorized the location of all the books on both floors. At the same time, the discomfort from deep mental exertion was becoming less and less severe.

Professor Yan assigned him a task today, so he needs to delve deeper into the relevant knowledge. He had previously dabbled in the MHD equations due to the need to study zero-gravity seats, but only within multiplier spaces. Now, he needs to further study the criteria for the NS equations and MHD equations in Triebel-Lizorkin space.

These three books were exactly what he needed. Of course, he also needed to download some related papers as a supplement to understand the latest developments and applications.

Holding the book, Ji Zhixing found a seat and began to read it eagerly.

"Magnetohydrodynamics" provides a comprehensive discussion, while "Generalized MHD Equations and Hall-MHD Equations" expands and extends upon them to a considerable extent. Ji Zhixing decided to borrow these two books and take them back to his dormitory or the laboratory to read them at his leisure.

"Ideal MHD" is divided into several parts: kinetic equations, derivation of velocity moment equations, magnetohydrodynamic equations, and two-fluid equations. It delves into the subject step by step with very detailed derivations, which is very suitable for Ji Zhixing's current needs, so he decided to start with this book.

Ji Zhixing had studied materials related to kinetic equations before, so he quickly finished reading the first part.

The derivation of the velocity moment equation in Part Two is crucial in transitioning from the microscopic Boltzmann equation to the macroscopic MHD equation. During the derivation process, one can understand the conditions under which the MHD equation applies.

The book derives the zeroth, first, second, and third order velocity moment equations.

Upon seeing the first moment, Ji Zhixing vaguely felt that the process of calculating the average velocity of a fluid was similar to the Navier-Stokes equations.

The second moment defines the viscous stress tensor. Upon seeing these words, Ji Zhixing quickly took out his notebook and wrote them down, as this part should be very helpful for the zero-gravity seat project.

After deciding to translate the theory in their paper into practice, they considered many issues that they hadn't previously had to consider.

The reaction force provided by the zero-gravity seat corresponds to the pressure exerted by the human body. When they designed the paper, they only considered the contact between the human skin and the seat surface under ideal or normal conditions.

However, in reality, the design of zero-gravity seats cannot be based on such an idealized state.

For example, with summer approaching, many people wear shorts and skirts when sitting on chairs. The skin inevitably experiences varying degrees of stickiness when in contact with the seat surface. This sticky stress tensor interferes with the zero-gravity effect to some extent. Ji Zhixing had been searching for a solution to this problem, and unexpectedly found inspiration in this book.

Of course, this part is also very helpful in completing the task assigned by Professor Yan. The composite material they focused on in the second phase is in a geometric gel state, and its viscosity is more prominent and complex.

Reading this book is truly killing two birds with one stone!

Ji Zhixing read with great interest, occasionally jotting down his understanding in his notebook.

"If the system is in local thermal equilibrium, then its distribution function is a local Maxwell distribution..."

Wow! You can use the distribution function like this! Integrating the distribution function over the Triebel-Lizorkin space yields a third-order tensor, which allows you to extract the total kinetic energy carried away by the macroscopic flow of the fluid.

Hmm? The total kinetic energy carried away by the macroscopic flow of the fluid? Ji Zhixing suddenly thought of the Navier-Stokes equations.

The Navier-Stokes equations themselves are not the entirety of fluid mechanics; often they need to be coupled with other equations to better solve fluid mechanics problems.

For example, Professor Yan's project introduced the MHD equations, and their zero-gravity seat project also introduced differential and partial differential equations.

For this reason, whether the Navier-Stokes equations in the three-dimensional case have a general solution and whether they are smooth has been questioned and explored by mathematicians, and many people even secretly look forward to the day when they malfunction.

However, the Navier-Stokes equations have indeed worked well to date and are widely used to simulate various physical systems, such as water flow and airflow. But the existence and smoothness problems remain unsolved, with only about a hundred particular solutions found to date. It remains one of the world's most prestigious Millennium Prize problems, and countless physicists and mathematicians around the world are tirelessly searching for answers.

Ji Zhixing had thought before that if he could see the answer in his lifetime, it would truly be witnessing history.

But at that moment, he suddenly had a reckless idea... a potentially feasible direction...

If we assume the total kinetic energy is a known condition, can we deduce several tensors and then solve for them?

If the total kinetic energy under different conditions can be used to deduce the same solution, then... can we prove that the Navier-Stokes equations actually have a general solution?

Of course, this may also involve some dissipation, L2 decay and Hs (s≥2) decay, and the isotropy of the two-dimensional partial viscosity. There are too many factors and it's too complex, but is this a direction worth exploring?

Ji Zhixing felt his heart was more acutely present than ever before, thumping and thumping as if it were about to jump out of his throat.

A note from the author:

None of the four sons of the Yan family will defect, don't worry.

"The key is to go from the microscopic Boltzmann equation to the macroscopic MHD equation. In the process of derivation, we can understand the conditions under which the MHD equation is applicable." "If the system is in a local thermal equilibrium state, then its distribution function is a local Maxwell distribution." These two sentences are quoted from "Ideal MHD (1) - Derivation of the Magnetohydrodynamic Equations".