The train driver in the courtyard

"A-choo! Who is talking about me again?"

Li Aiguo sneezed, and walked towards the Beijing Zoo, holding Xiao Hongsheng in one hand and the panda Chichi in the other.

"Dad, can't we keep Chichi here?" Xiao Hongsheng and Chichi have become good friends now and is reluctant to let it leave.

Li Aiguo stopped and rubbed his little head: "Chichi is a panda, he needs to play with his own kind. He lives in the zoo, you can come and see him anytime if you miss him."

Although Xiao Hongsheng didn't understand, he knew that humans were different from animals. He could only lower his head helplessly and follow Li Aiguo.

This is not the first time that Li Aiguo has come to the Beijing Zoo, and he always sees enough.

There are all kinds of animals such as wild wolves, black bears, and sika deer.

"Look, in front is the elephant park, which has elephants sent by African friends."

Li Aiguo walked over quickly, wanting to find out what was going on.

As soon as I saw it, I couldn't help but shout, "Hey, how could you eat bananas secretly?"

I saw a fat man weighing about 300 pounds squatting next to the elephant and stuffing the banana that was supposed to be fed to the elephant into his own mouth.

The elephant has lost weight.

The person has gained weight.

"Is this reasonable? Is this reasonable? Is this reasonable? It's just eating a few bananas. Is there any need to yell?!" the fat man stood up.

Little Hongsheng felt sorry for the elephant, so she stepped forward and asked in a baby voice, "Uncle keeper, why did you steal the elephant's food?"

"Hey, hey, hey, kid, don't frame me!"

The fat man grabbed the elephant's trunk and stood up, pointing his finger at himself: "I am a zoo keeper and a zoo employee."

The fat man pointed at the elephant and said, "It's a zoo animal and a zoo employee."

"We are both employees! Our shoulders are the same height. Why can an elephant eat bananas but I can't?"

Xiao Hongsheng: “.”

Li Aiguo: "."

He always felt that this guy was making trouble.

If all zoo keepers were like him, then zoos should stop raising animals and just raise keepers.

But this guy has a nice name, Zhang Yue.

Zhang Yue is a little greedy and a bit fussy, but he is a warm-hearted person.

When he learned that Li Aiguo was going to donate the pandas to the zoo, he immediately greeted him with a smile and took Li Aiguo and Xiao Hongsheng to the panda house next door.

Li Aiguo saw Zhang Yue take out the key from his waist and open the door, and asked curiously: "Comrade Zhang Yue, how did you get the key?"

"Oh, I forgot to tell you that in addition to taking care of the elephants, I am also responsible for taking care of the giant pandas."

Xiao Hongsheng was startled and quickly hugged Chichi tightly: "Dad, we can't leave Chichi to him. What if he eats all of Chichi's food?"

Zhang Yue patted his stomach, pointed at the bamboo not far away and said, "I want to eat it, but my teeth won't let me."

Indeed, if this fat guy could chew bamboo, he should go to the circus to perform.

When Director Chen of the zoo learned that Li Aiguo was bringing food, he put down his work and rushed over.

After the veterinarian's examination, it was confirmed that Chi Chi was healthy.

“Thank you so much, patriotic comrade!”

Director Chen handed Li Aiguo a big award certificate.

Li Aiguo took the certificate and said with a smile, "Director, I will come to visit often in the future."

"It's my duty!" Director Chen continued with a smile, "We are preparing to build a special giant panda breeding base. Then, Chi Chi will be able to get better care." Hearing this, Li Aiguo felt relieved.

In the evening, Li Aiguo came to Chichi’s new home to say goodbye.

Although Zhang Yue is greedy, he is reliable. He cleans the place where he eats and lives and even puts apples on the table.

At this time, Chi Chi was having fun with several adult pandas.

Li Aiguo felt that handing Chichi over to the zoo was the right decision - although this little guy is called a panda, it is essentially a bear, not a cat.

****
time.

Like a girl's first kiss.

Always come and go in a hurry.

Facts have proven that if you don’t push yourself, you’ll never know how awesome you are.

When all the work was done, Li Aiguo was shocked by his own speed.

He actually compiled a complete paper proving the Poincare conjecture in just ten days.

Of course, the help of Beijing University and the Institute of Mathematical Computing of Beijing University is also indispensable.

The higher-ups attached great importance to this review, and even Chen Zihua was pulled in to serve as a soldier.

The paper is thirty-one pages long and the title is very simple, with only one sentence - any simply connected, closed three-dimensional manifold must be homeomorphic to a three-dimensional sphere.

Mere proof is empty and boring.

Li Aiguo elaborated on the theory of Li Aiguo Flow in detail and created a "mathematical heat flow" to soften the plasticine, allowing it to shrink naturally into a sphere, and perform "surgical repair" if it is deformed in the middle.

The elaboration of this theory took considerable time.

Finally, before the review meeting, Li Aiguo finally submitted the paper to the committee.

Li Aiguo submitted his paper two days later than expected.

The members of the organizing committee who were paying attention to this paper also waited for two full days.

When the organizing committee received the paper, volunteers at Beijing University got the news in less than an hour.

For a moment, the campus, which was originally as calm as water, suddenly became boiling.

"Great, the paper has finally been submitted. Now we can look forward to the review meeting at the end of the month."

"Speaking of which, this is the most important conference held by our Jingcheng University in recent years."

"Yes, take the mathematicians who came to the conference, for example, any one of them is a big shot."

"Haven't you noticed that there are a lot of gray Zhongshan suits in our school recently?"

Lao Mao was doing a routine inspection with several comrades from the weather station. When he heard the students' discussions, he couldn't help but hold his forehead.

In order to ensure the safety of the mathematicians and avoid any unpleasant incidents, the "security" work of the review committee was handed over to Lao Mao.

This made the old cat feel a little depressed.

He was originally a sword, but now he has to act as a shield.

A weatherman nearby muttered, "Team leader, I'm a little confused."

The old cat stopped and looked at him.

The weatherman whispered, "The identities of these foreigners are very sensitive. In the past, according to regulations, just contact with them would require strict review.

Now, the driver wants to discuss math problems with them and we have to protect them."

In fact, the views of the junior meteorologists are also quite common in the weather stations.

Especially the meteorologists who entered the meteorological station through formal selection channels after liberation.

Although they are determined, they have never experienced real combat and are only full of enthusiasm.

In their view, fighting is fighting. There is no need to use fancy moves. As long as they keep moving forward, they will win in the end.

The old cat had wanted to teach them a lesson for a long time, but he just never got the chance.

He took the opportunity to gather a few young meteorologists together and said in a low voice: "What is the purpose of setting up a weather station?
It is to safeguard the construction of the motherland and for the safety and happiness of the people, not to investigate for the sake of investigating or to punish people. "

"I don't understand the proof that the driver produced, but it has now attracted the attention of these great professors."

"These great professors are well-known figures abroad. One sentence from them is worth thousands of sentences from our propaganda department comrades."

"Building a good relationship with them will help us gain greater support within this big family."

“In the current climate, this support is even more important.”

Seeing that some weathermen still didn't understand, Lao Mao emphasized: "If you want to achieve the final victory, you can't just vent your emotions. Instead, you have to make your enemies as few as possible, make your friends as many as possible, and win all the support you can."

After these words were spoken, the expressions of the young meteorologists relaxed a little.

Lao Mao didn't blame them. After all, these people were still very young and it was normal for them not to understand the deeper meaning of the above.

"Let's carry out the mission! From now on, the auditorium is completely closed and no one is allowed to approach." The old cat warned solemnly: "If these mathematics professors have any problems here, it will cause serious consequences. You know it!"

"Yes!" Although these young people still didn't quite understand, they had received professional training and were a truly disciplined team, so they carried out the mission without hesitation.

After assigning the tasks, Lao Mao called Captain Zhang to his office: "Lao Zhang, there is a flight from Moscow that will land at Nanyuan Airport this afternoon. There is a reporting team from the Asahi Shimbun on the plane. Their identities are very sensitive. You will personally lead the team to be responsible for the security work."

Captain Zhang is an old comrade, and he nodded without hesitation: "Team leader, don't worry, I promise to complete the task."

[Japan Airlines (JAL) and the Soviet Civil Aviation Administration (Aeroflot) reached an agreement in the early 60s to jointly operate the Moscow-Tokyo route using the Soviet Ту-114 passenger aircraft]

At the same time, the Friendship Hotel was also ready and vacated two entire floors to receive foreign guests coming for the meeting.

The morning of September 1960, 9.

Mathematicians from all over the world gathered at Keijo University for the review conference.

Reporters from major newspapers around the world, wearing special credentials and accompanied by weather station staff, arrived outside the auditorium of Keijing University.

From time to time they pointed their cameras at the volunteers in the distance.

The meteorologists turned their heads and cast inquiring glances at Old Cat, who was in charge of on-site command.

The old cat shook its head, and the signal it sent was very clear: the other party was just taking pictures and didn't do anything inappropriate, so there was no need to pay attention to it.

In fact, before being allowed to enter Jingcheng University, these reporters had signed an agreement clearly stating the scope of their interviews.

Moreover, most of the reporters who can come here have a good relationship with us.

After all, in that era, the proletariat was one family.

Our comrades are working in both Xiaomei's and Xiaoou's homes.

These comrades are spread across all walks of life, including many newspaper reporters.

As time passed, mathematicians from all over the world, accompanied by staff, arrived at the entrance of the Great Hall of Beijing University one after another. They did not rush to enter the auditorium, but stood there and exchanged academic ideas enthusiastically.

After all, academic research cannot be done behind closed doors, and a word from a colleague may be able to solve a problem that has troubled you for months.

All the participants in this conference are top international mathematicians. They also want to take this rare opportunity to broaden their international horizons and lay the foundation for future academic research.

At seven o'clock in the morning, a black sedan drove into Jingcheng University and stopped directly in front of the auditorium.

A middle-aged man got out of the car, and many mathematicians present exclaimed in surprise when they saw him.

“It’s Alexander Grothendieck! He’s been living in seclusion, so why is he here?”

As a well-known mathematician in the international mathematics community, Professor Alexander Grothendieck attracted everyone's attention as soon as he appeared.

The reporters who had been waiting for a long time immediately surrounded them.

The reporter from Le Monde quickly pulled out his notebook and asked, "Professor, have you read Li Aiguo's paper?"

"If you are talking about the first one, I have indeed read it. As for the second one, I think I will be able to see it soon." Alexander Grothendieck's answer was as humorous as ever.

The reporter then asked: "Do you think his proof will be successful this time?"

“It seems that you want me to play God.” Alexander Grothendieck responded with a smile, “I don’t mind, but I don’t know if God agrees.”

The reporter smiled awkwardly and changed the question: "What do you think of Li Aiguo's first paper?"

Alexander Grothendieck raised his eyebrows and gave four words: "Genius!"

The reporter wanted to continue asking questions.

At this time, other mathematics professors gathered around.

"Grothendieck, I didn't expect you were still alive."

"Hahaha, there's nothing I can do. That old guy God got confused and forgot that I'm still wandering around in the world."

Today, Zong Xianfeng was also temporarily assigned to maintain order at the scene.

Looking at the star-studded scene, he couldn't help but smack his lips: "This is the first time I've seen such a grand scene."

"Zong Xianfeng, how have you been lately?"

Hearing the pleasant voice, Zong Xianfeng looked in the direction of the sound. When he saw the person coming, his eyes lit up and he quickly walked towards him.

"Comrade Dasha, why are you here too?"

Since Li Aiguo's last reminder, Zong Xianfeng deliberately distanced himself from Dasha, and the two have not met for nearly a month.

"All of us international students have been transferred here as volunteers. Have you been on a business trip recently? Why haven't I seen you?" There was a hint of anger in Dasha's tone.

Zong Xianfeng scratched his head embarrassedly: "I've been too busy with work recently..."

Dasha understood Zong Xianfeng's concerns and changed the subject: "Zong Xianfeng, you are doing physics research, when can you hold such an audit meeting?"

"Me? Forget it."

"You are the pioneer of the sect, the prodigy of the past. Why do you have so little confidence?"

In those days, the number of college students admitted nationwide each year was limited.

Zong Xianfeng was able to be admitted to Beijing University and stayed on to work at the university after graduation. He is undoubtedly one of the best among the best.

However, Zong Xianfeng had no confidence at this time.

He stood at the door of the auditorium, looked at the dark crowd, smiled and shook his head.

"forget it……"

After all, who among those who can appear here is not an elite?

Seeing Chen Xueru, Aunt Liu and He Yushui coming over, Zong Xianfeng hurriedly walked over to greet them.

"Sister-in-law, Auntie, Sister Yushui, you are here too."

Chen Xueru looked around the scene and said with a smile: "Today is an important day for Aiguo Ge, we must come to cheer him on!"

He Yushui turned his gaze towards the mathematicians and exclaimed in a low voice: "So many foreigners...are they all here to listen to Brother Aiguo's lecture?"

At this time, Chen Ziliang also arrived, and when he saw the three of them, he came over. After greeting them, He Yushui asked Chen Ziliang: "Teacher Chen, you are also a mathematician. When can you hold a meeting like this?"

Chen Zihua was speechless for a moment.

He thought that He Yushui's study attitude had been poor recently, so he had to give her more homework.

At nine o'clock, the auditorium was already crowded with people.

The first few rows were reserved for foreign professors, while the back rows were filled with students, lecturers and professors from Beijing University. Even the corridors were filled with people, making the place extremely lively.

Reporters from Renren TV set up cameras next to the podium. Once Li Aiguo's paper passes the review, these video footage will be invaluable.

In fact, many foreign TV stations have already reserved the rights to broadcast the video in advance.

Dasha stood in the corridor, looking at Li Aiguo sitting in the center of the rostrum, took a deep breath, and whispered: "Come on, Brother Aiguo, you can do it."

At this time, a middle-aged man walked up to her, nodded and said, "Don't worry, he will be able to do it."

Dasha looked up and was stunned for a moment before she remembered the other person's identity: "Professor Hua, why are you here?"

"He is my student, how can I not come?" Professor Hua said calmly after taking a look at Li Aiguo who was preparing materials.

"Hua, you are absolutely right." Hearing the familiar voice, Professor Hua immediately guessed who it was. He turned around and saw Professor Eisenhart sitting next to him.

"Teacher, you are here too."

"Oh, your question is strange. My student's student has made achievements, which is equivalent to my student's achievements. As a teacher, how can I not come to show my support?"

Professor Eisenhart stood up and held Professor Hua's hand tightly. "Hua, when you abandoned Princeton and came back here, I was against it. But now that I see that you have trained such an outstanding student, I finally understand your real purpose."

"Teacher" Professor Hua's expression was somewhat moved.

In order to return to China, he had a very unpleasant argument with Professor Eisenhart.

Professor Eisenhardt had persuaded him several times to stay in Princeton so that he could make further progress in the academic field.

However, seeing that Professor Hua was stubborn, Professor Eisenhart not only helped him with the formalities but also lent a hand when he encountered difficulties.

When Professor Hua saw his teacher again, his nose felt sore.

"Okay, now that you have established your own school, stop acting like a child." Professor Eisenhart smiled and took Professor Hua's hand and sat down.

"It's about to begin." He turned his head and looked at the podium.

This was not the first time Li Aiguo had experienced such a big scene, and he thought he would not be nervous.

However, when I looked around the audience and saw mathematicians from all over the world, my heart couldn't help but pound.

He knew very well that what he represented at this moment was not just himself, but also the Department of Mathematics of Beijing University, the Beijing Institute of Mathematical Computing, and even the entire domestic mathematics community.

The greater the ability, the greater the responsibility.

Seeing Professor Cheng give the start signal, Li Aiguo took a deep breath and tried to calm himself down.

"here we go!"

The time came to half past nine.

The professors in the auditorium seemed to have received a unified command and fell silent instantly.

Li Aiguo turned around and uncovered the white cloth covering the blackboard. A line of large characters came into view: "Proof that any simply connected, closed three-dimensional manifold must be homeomorphic to a three-dimensional sphere."

After looking around, Li Aiguo spoke slowly.

"Just because Columbus sailed around the earth, does that mean it can prove that the earth is a sphere? No!"

"For thousands of years, we have always been accustomed to everything we take for granted, and have not paid attention to exploring the secrets behind these things."

“Since its birth, mathematics, with its rigorous logic, has been destined to become our second pair of eyes to observe the world.”

"Back to the question just now, why can't Columbus's circumnavigation of the earth prove that the earth is a sphere? Because the earth may also be in the shape of a donut."

"So how do we prove that the Earth can't be a donut?"

"Now, it's time to use mathematics and this special pair of eyes to solve this problem."

This concise and brilliant opening speech instantly attracted the attention of all the mathematics professors in the audience.

The scene was silent, and everyone's eyes were focused on this young man, afraid of missing any details.

"First, we introduce the Lie Aiguo manifold theory, which is a geometric evolution equation that drives the deformation of the manifold through curvature, making it tend to a uniform geometric structure. Where gij is the metric tensor of the manifold, and Ricij is the Lie Aiguo curvature tensor."

This part of the content has been published in the first paper, and Li Aiguo explained it very quickly.

"In the evolution of Li Aiguo's manifold, the manifold will not collapse infinitely in a local area, that is, the curvature explosion will not cause the volume to collapse to zero. I call this the non-collapse theorem."

"At the same time, we introduce the concept of topological surgery, which removes the singularity region and fills it with standard geometric blocks, keeping the overall topological structure of the manifold unchanged."

“The concept of entropy is introduced to quantify the geometric complexity of the evolving manifold, ensuring that the surgical process is controllable.”

“Through repeated applications of Li Aiguo and topological surgery, eventually the manifold will be split into several geometrized pieces.”

"If the original manifold is simply connected, then all geometrized blocks must degenerate into a unique spherical geometry, namely S3!"

In the audience, Professor Grothendieck sat in the center of the front row.

As Li Aiguo continued to explain, his expression gradually became solemn, and the pen in his hand began to move rapidly.

"How is it?" Sitting next to him was Professor Arnold from the School of Mathematics of Moscow State University, who had made great achievements in algebraic geometry, magnetohydrodynamics, partial differential equations and other fields.

At this time, Professor Arnold could no longer keep up with Li Aiguo's train of thought.

"Shut up!" Grothendieck seemed disturbed and looked very unhappy.

Professor Arnold was shocked and thought to himself: Could it be that the proof of this young man on the stage is really valid?
Otherwise, given Grothendieck's character, he would have stood up and scolded the other party for wasting time.

He shrank his neck, leaned back in his chair, and narrowed his eyes.

What is the origin of this young man from Jingcheng University?
As a top Russian mathematician, Professor Arnold has had many exchanges with Jingcheng University and is well aware of Professor Hua's strength. In his opinion, Professor Hua cannot teach such a student.

Is it true that "the pupil surpasses the master"?
The wisdom of the ancient Chinese is truly amazing.

In the front row of the auditorium, Chen Xueru sat side by side with Aunt Liu and He Yushui. She was extremely nervous.

There shouldn’t be anything wrong with Brother Aiguo’s argument, right?
But the old professors nearby also looked confused.

(End of this chapter)