Great Country Academician

It’s different from other fields that do some ‘fancy work’ from time to time.

For example, there is a wave of discoveries of "normal temperature superconductivity" in the material world from time to time, such as the annual Nobel Prize winner contest in the physics world, and what new particles and new cosmic phenomena have been discovered in the theoretical physics world.

By comparison, it can be said that there is very little ‘gossip’ or very few ‘interesting’ things in mathematics.

The Fields Medal is given once every four years, and the Nobel Prize has no place in it. Even ordinary math students cannot understand various mathematics papers.

In this case, the proof of the top-bound conjecture is undoubtedly one of the few big ones in this boring field.

Therefore, the research paper on the weak Riemann hypothesis that Xu Chuan posted on the arxiv preprint website is naturally the focus of the world at the moment.

This is no exception for the holy places of mathematics, Princeton University and the Institute for Advanced Study.

If I had known that when Xu Chuan posted his previous tool paper on the weak Riemann hypothesis on arxiv, Princeton University, especially the mathematics department, would be full of professors and students discussing this matter.

Even if you chat with someone casually, the topic will not unknowingly shift to the Riemann Hypothesis.

"The weak Riemann hypothesis has been proven!"

"That's impossible, stop joking."

"It's true. The certifier is Professor Xu! The papers have been uploaded to arxiv!"

"Who? Professor Xu? That Professor Xu from China?"

"Nonsense, besides him, are there any other mathematicians named Xu?"

"My God, this is incredible. I remember he uploaded a research paper just a week ago, right? How long has it been? Has the weak Riemann hypothesis been solved by him?"

"If the Riemann Hypothesis was solved by him, he would have solved four of the Millennium Problems by himself!"

"Tsk, tsk, this is a total of four million meters of gold!"

"If even one of the Millennium Problems can be solved, what is four million meters of gold?"

"Eh? Speaking of which, it seems that Professor Xu has not received the award at the Clay Institute of Mathematics, right? Neither has Professor Perelman, who solved the Poincaré conjecture before. It seems that everyone who solved the Millennium Problem is right. Money lost interest.”

"Envy, if only I could solve one."

"Wake up, stop dreaming!"

There was a lot of discussion on the Princeton campus.

The seven Millennium Problems are the focus of the mathematical community, and each problem is linked to the Cray Mathematics Institute's one million gold.

This is a huge sum no matter which country it is placed in. It is enough for an ordinary person to have enough food and clothing for a lifetime.

But unfortunately, four of the Millennium Problems have been proven, and none of the prize money prepared by the Clay Mathematics Institute has been distributed yet.

As mentioned in the chat, the scholars who have solved the seven millennium problems seem to have lost their desire for money.

The discussion at Princeton University is just a microcosm in the mathematics world.

Compared with math students and most mathematics professors who are discussing whether the weak Riemann Hypothesis has been proved or not, those experts who are truly at the top of the pyramid in the mathematics world are focusing on different things at the moment.

Germania, Planck Institute for Mathematics.

An old man wearing a wool sweater was sitting at his desk, frowning and staring at the densely written manuscript paper on the table.

On the side, there is a whole stack of papers that have obviously been read countless times, and the notes on them are equally densely scattered everywhere.

At this moment, there was a knock on the door of the office twice, and then, a slightly fat white man walked in. He was not very old. It seemed that he should be a doctoral student under Faltings' guidance. He was holding a bag in his hand. Stacking manuscript paper and carrying a lunch,

"Professor, the manuscript paper you requested and the lunch you ordered have arrived."

Faltings said calmly without raising his head: "Put it there."

"Okay." After the doctoral student put the lunch in his hand next to his desk, he took two steps forward, put the manuscript paper where Faltings could easily reach it, and then stood hesitantly. There, he looked like he wanted to ask questions but didn't dare.

Realizing that his student had not left, Faltings raised his head, glanced at him, and asked coldly: "Is there anything else?"

After hesitating for a while, the doctoral student said: "Professor, is Professor Xu right about the paper on the weak Riemann hypothesis?"

Faltings: "To this kind of question, you should find the answer yourself."

The corners of the doctoral student's mouth moved, but he stopped talking.

If he could understand that paper, why would he be asking here?

With his eyebrows twitching and a look of helplessness on his face, the doctoral student said, "Okay, professor, if there's nothing else, I'll leave first."

Faltings did not answer, and his eyes fell back on the manuscript paper in front of him.

There, a research paper on a quasi-Riemann Hypothesis seemed almost complete.

Judging from the proof idea of ​​the paper, the research above seems to be developing in the direction of the left translation route of the right boundary, which is the most difficult to break through.

However, the latest handwriting has stayed on one day ago

On the other side, Huaguo, Jinling.

In the Qixia Mountain New Development Zone near the Yangtze River, there is a newly built research institute.

The buildings in the courtyard are not very tall, and the tallest main building only has about ten floors. Compared with the dazzling array of high-rise buildings in the surrounding development areas, which often have dozens of floors, they are nothing.

However, the technology and patents flowing out of this research institute, which does not occupy a large area, have supported many surrounding companies or factories.

In the Chuanhai Materials Research Institute, Xu Chuan knocked on the door of Master Xiong Fan Pengyue's office, and then opened the ajar door and walked in without waiting for a response from inside.

In the office, Fan Pengyue, who was sitting behind the desk and dealing with the work at hand, raised his head and was about to shout "come in", but before he could say anything, he saw Xu Chuan walking in.

Seeing the person coming, he was stunned for a moment, then stood up quickly, came over and greeted with a smile: "Junior brother, have you solved the Riemann Hypothesis?"

Although he is not studying mathematics, as a fellow student and his immediate boss, he still knows Xu Chuan's character very well.

When his junior brother enters a certain research field, it is basically difficult to see him outside without solving the problem or solving it in stages.

If this appears here, then there must be some breakthrough in the problem he is researching.

Xu Chuan smiled and said: "It would be great if we could really solve the Riemann Hypothesis."

If he could solve a century-old problem like the Riemann Hypothesis in just one month, the entire mathematical community would probably go crazy.

Fan Pengyue smiled and made tea, and joked with a smile: "The problems you are targeting will be solved sooner or later. This time, it will not be far away next time."

Although he looks tall and rough, Master Xiong still has some ideas of his own on how to maintain the relationship between the two.

Although the two of them met less than once throughout the year, he never showed his unfamiliarity in front of this junior brother, even though Xu Chuan had already reached a height that was beyond his reach.

It is precisely because of this that Xu Chuan can be considered relaxed here and has an ordinary friend who can talk nonsense.

After chatting for a cup of tea, Xu Chuan cut the topic to the main topic.

"By the way, you sent me an email two days ago, saying that there have been some breakthroughs in lithium-sulfur battery research. How is the situation now?"

To be honest, he is not actually a researcher in the battery field.

Previous research on artificial SEI films was just a 'reproducible' result based on some memories from a previous life in the mind.

After all, this technology will actually be completed by a research institute in the United States in the future, and it can only be regarded as a 'borrowing'.

When talking about business, Fan Pengyue also suppressed the smile on his face and said: "The main problem of lithium-sulfur batteries is basically the sulfur material. You know this very well, little junior brother."

"The use of sulfur materials can indeed greatly increase the energy density of lithium batteries. According to our research on lithium-sulfur batteries in the past two years, the energy density of previously manufactured laboratory samples can reach 3000Wh/kg."

"However, during the continuous charging and discharging process, the formation of sulfide and its irreversible effects will quickly damage the battery's capacity and life, which also makes it difficult for lithium-sulfur batteries with high energy density to appear on the market."

Xu Chuan nodded. Although he was not a scholar or researcher in the battery field, he had led a team to study lithium batteries and artificial SEI films before, and he also understood some of the development and major problems of this industry.

For example, in lithium-sulfur batteries, after artificial SEI films have solved the problem of lithium dendrites, the remaining problems in lithium-sulfur batteries mainly lie in three aspects.

First, lithium polysulfide compounds are dissolved in the electrolyte. Second, sulfur is a non-conductive substance with very poor conductivity, which is not conducive to the high-rate performance of the battery. The third point is that the volume of sulfur expands and shrinks very much during the charge and discharge process. If too large, it may cause battery damage.

The three questions basically focus on sulfur.

But the advantages of lithium-sulfur batteries are also very obvious.

Due to the use of sulfur-carbon composite as the positive electrode material and lithium metal as the negative electrode, the energy density of lithium-sulfur batteries is much higher than that of traditional lithium-ion batteries.

Before the lithium dendrite problem was solved, the Argonne National Laboratory under the U.S. Department of Energy successfully developed and tested a new lithium-sulfur battery in the laboratory.

Its energy density can reach 2300Wh/kg, far exceeding the 200Wh/kg energy density of lithium iron phosphate batteries and ternary lithium batteries at that time.

This is enough to give an ordinary electric car a theoretical range of more than 3,500km, which is even longer than the lithium-ion battery life after the emergence of artificial SEI films.

From this, it is enough to see the excellent performance of lithium-sulfur batteries.

Opposite, Master Xiong stood up and walked to his desk, bent down, found a document that he had prepared long ago from the drawer, and handed it over.

"I guess you didn't read much of the email I sent you. This is a detailed report on lithium-sulfur batteries. You should read it first."

Xu Chuan took the document, opened it and said, "Tell me about your research ideas and processes in the past two years."

Although he is not engaged in R\u0026D in the battery industry, he is still very interested in the R\u0026D process of Chuanhai Materials Research Institute in the past two years.

After all, after the completion of lithium-sulfur batteries, the next focus will undoubtedly be more advanced lithium-air batteries with higher energy density.

Although he may not have time to participate personally next, it is also good to understand the changes in lithium-sulfur batteries.

As for listening and watching at the same time, it is not too difficult for him to do two things at once.

"OK."

Fan Pengyue nodded, responded, thought about and sorted out the research process of the past two years in his mind, and slowly narrated.

"Later, we want to change the properties of the electrolyte and break through these problems according to your previous ideas of studying artificial SEI films and solving lithium dendrites."

"We tried and succeeded in creating a new lithium-sulfur battery by replacing the carbonate electrolyte with an ether electrolyte that does not react with polysulfides."

"However, during testing, it was found that the ether electrolyte itself is extremely volatile and contains components with low boiling points, which means that if it is used to make batteries and the temperature of the battery is heated above room temperature, it may soon fail or melt."

“Attempts have also been made to reduce the amount of electrolyte and stabilize the lithium metal anode to solve the problems encountered by lithium-sulfur batteries.”

"Although these studies were not successful, they also accumulated a lot of experience for us."

"Of course, it will consume a lot of money."

Xu Chuan flipped through the documents in his hand, nodded and didn't pay much attention.

The research and development of any kind of material or experimental product, aside from those "white" European and American foreigners, can be said to be successful only after trying little by little, slowly accumulating experience and eliminating wrong options and routes.

It is not a problem to develop lithium-sulfur batteries before other countries and consume some funds.

Moreover, even if the experiment fails and no particles are recovered, these data are still very important to the Sichuan-Hai Materials Research Institute.

This is the reason why it is difficult to overtake in corners and can only be accumulated bit by bit in the field of materials.

If you don't have experimental data on the route that others have taken, you can only know the results after trying it yourself.

And if you have data in hand, then you can easily eliminate this direction, this route, and then use the saved time, energy, funds and other things on other routes that may be successful.

In this case, it can be said that one step is the first step, and it is naturally very difficult to achieve overtaking in corners.

To be honest, Xu Chuan was a little surprised that the Chuanhai Materials Research Institute was able to complete lithium-sulfur battery technology before other manufacturers and scientific research units.

In recent years, he has not had time to take care of the research institute, and has basically been busy with his own career. Even he told Fan Pengyue some of the developments in the battery field that he remembered from his previous life. The background of Sichuan and Hai Materials Research Institute, compared with other battery manufacturers and R\u0026D institutions are still quite weak.

Being able to take the lead in completing lithium-sulfur battery technology before other battery manufacturers did surprise him.

However, this seems to have something to do with the material calculation model he created before?

Looking at the data on the report document, Xu Chuan's eyes fell on one of the pages, and he remembered the mathematical model of materials that he had forgotten for a long time.

If it weren't for this breakthrough in lithium-sulfur batteries, he almost forgot that he had deployed it in this field.