"Welcome to my open lecture, today's main content is about the proof and application of topological group theory, and I will also set aside time to answer your questions after class."

July 22, 2018, 2:30 p.m., Princeton University Open Class Classroom.

Xu Yun stood on the podium, facing the figures below who said two or three hundred less in English.

He didn't prepare anything before, so he relied on the play.

Fortunately, the process of perfecting and proving topological group theory was all stored in his mind, and there would be no surprises.

Meanwhile.

Since the public class had not yet officially begun, I could vaguely hear the whispers of Princeton students talking below.

"Is this a math genius from China, I didn't expect him to speak foreign languages so well."

"It's really desirable to be able to prove the world's mathematical problems."

"It's actually about topological group theory, and today's open class is not in vain."

"My God, who looks younger than we are, has already performed miracles."

"Didn't Professor Vicky say that the topological group theory is not valid?"

"He's the most handsome oriental face I've ever seen, and it would be wonderful to have a date with him in the evening."

……

Xu Yun didn't take these discussions to heart, and when he began to explain the relevant content of topological group theory, the audience suddenly became extremely quiet, and all eyes were focused on Xu Yun.

"Topological group theory is what I proposed to prove that there are infinite primes in the Fibonacci sequence."

"The main thing is to add topology on the basis of the sieve method, and optimize and improve it."

"Happily, I have recently thoroughly demonstrated the feasibility of topological group theory, which will help us to reach the highest temple of number theory."

Magnetic words and sentences came out of Xu Yun's mouth, and then he wrote mathematical formulas on the blackboard.

"Set of prime numbers P={P1,P2,P3,...,Pn,...}"

"Range Z."

“A（N）={a｜a=N-P，P≤N}”

……

As time passed, there were more and more mathematical formulas on the blackboard under Xu Yun's narration.

Although Xu Yun has simplified as much as possible by relying on his own ability, it is still very difficult for many students to understand.

The expression of anticipation and interest slowly became solemn.

After all, the improved topological group theory can be used to prove the number theory problem.

It's normal for ordinary people to be incomprehensible.

Even if you are a graduate student majoring in mathematics, you have to be blind to the complex formulas in front of you at this moment.

Being able to understand a little bit shows that he has a talent for mathematics.

At the same time, this also makes everyone understand the gold content of Xu Yun's open class, which can be said to be no weaker than that of the professors of the Institute for Advanced Study.

Like the professor of the Department of General Mathematics, the level is also a lot lower than Xu Yun.

And Vicky, who was also sitting in the audience, did not listen to the lecture at the moment, but took a draft paper and quickly calculated on it.

If someone approached him at this time, he would have been able to hear the words repeating over and over again.

"It's certainly impossible to prove."

"Impossible."

"I can't be wrong."

"We can definitely find an entry point to disprove this theory."

He has been a professor of mathematics at Princeton University for decades.

There is an absolute trust in yourself.

Since it is determined that the topological group theory is not valid, it is necessary to do everything possible to overturn it in this case.

When the Hodge conjecture proof was released, mathematicians around the world did the same.

It's a pity that he still underestimated Xu Yun's talent and strength.

After learning about the proof process, he calculated it on his own, trying to find an entry point for overturning.

For this reason, the content that Xu Yun talked about later was hardly calm.

However, seeing that the public class was about to end, he never found a place where there was a problem that could be overthrown.

Deligne and Witten, who were not far away, looked at Xu Yun with admiration and excitement in their eyes.

"This kind of talent and understanding of mathematics is by no means inferior to Gauss, the prince of mathematics in history, and it is a pity that he is not a student of Princeton University."

"Maybe we can invite him to join us at the Institute for Advanced Study." Witten turned his head when he heard Deligne's emotion.

The speaker has no intention and the listener has a heart.

Hearing this, Deligne's eyes lit up and began to think in his heart.

"I believe that topological group theory will be widely used in the field of number theory, and I welcome everyone to continue to optimize it."

"That's all for today's lecture, thank you."

At this time, Xu Yun on the stage finished his conclusion and announced the end of this open class, and the students who were already extremely excited in the audience suddenly stepped forward.

The scene was very lively.

"Can I take a picture with you, teacher?"

"Can you give me your contact information, I want to go on a date with you."

"You're amazing."

"This class is very exciting, and I will continue to explore math with you as an idol."

"Mr. Xu, I am an international student from Jinghua University, and I am so happy to see you here."

Compared with the students of Jingzhou University, Princeton University is undoubtedly more bold and proactive.

Among them, several blonde female students were so outspoken that Xu Yun was almost overwhelmed.

Of course, the contact information will definitely not be given, and he has no idea of having a transnational relationship, and in the end he just said his personal email address for the exchange of mathematics-related issues. Anyway, his personal email address is not strictly a secret, and it will not affect his life.

After nearly twenty minutes passed, and after the number of people in the classroom had been greatly reduced, he broke out of the encirclement and walked towards Delineweten and the others who were still sitting in the audience.

"Professor Deligne."

"Professor Witten."

may be because some female students were too active just now, Xu Yun's face was still a little ruddy when he greeted him.

Looks embarrassed.

"Your talent and potential are even higher than I imagined, and with your topological group theory appearing in the field of number theory, I believe that it will not be long before the famous conjecture of number theory, which has plagued the entire mathematical community, will be advanced."

Deligne stood up with a smile on his face, wishing that Xu Yun was his student.

Although his field of study is mainly algebra, it is impossible not to understand number theory at this level.

Naturally, we can see the value of topological group theory.

Next to him, Witten answered: "If you can see all the world's mathematical problems solved in your lifetime, then there will be no regrets." ”

Xu Yun listened to the emotion of the two math bosses, and his face seemed to be very calm, but his heart was very active.

How did Drigne know that he had applied topological group theory and thoroughly proved Goldbach's conjecture.

I don't know how they'll react when they hear the news.

Just as Xu Yun was thinking, Vicky, a professor of mathematics who was sitting not far away, finally threw away the pen in his hand.

After being stunned for a few seconds, he slowly got up and walked to Xu Yun.

"My previous decision was wrong, and topological group theory is indeed feasible and can be used to prove number theory problems."

"Your research and understanding in the field of number theory is far above mine."

"I apologize for what I said earlier."

Vicky eventually accepted reality, and after discovering that he couldn't overturn Xu Yun's proof at all, he realized how ridiculous his previous decision was.

It turns out that it is not that the topological group theory is not valid, but that his limited level is not as good as Xu Yun's understanding.

It is more serious for him not to accept the truth in mathematics than to accept his mistakes.

So he made the decision to approve and apologize in front of everyone in front of the topological group theory.

The students who had not left the classroom naturally knew Vicky, and after seeing their professor take the initiative to apologize, they were even more surprised in their hearts, and realized how valuable the open class just now was.

But before they could calm down, the words that Deligne said next were even more shocking.

"There's another thing I'd like to ask your opinion, would you like to join the Institute for Advanced Study in Princeton?"

"Join the Institute for Advanced Study?"

Xu Yun was a little stunned when he heard Deligne's words, but he didn't expect the other party to suddenly invite him to join.

There is no doubt that the Institute for Advanced Study in Princeton is much more valuable than the Institute for Advanced Study in Mathematics at Jingzhou University, after all, members like Delineweiten have won Fields Medals.

So far, there are only a few members of the Institute for Advanced Studies of Beijing University.

Just when Xu Yun fell into deep thought, Vicky next to him was full of envy, and even wanted to agree for Xu Yun.

He has been in the Department of Mathematics at Princeton University for so long, and has not been able to join the Institute for Advanced Study, and now Xu Yun has not only obtained the qualification to join, but the key is that Deligne personally invited, just this kind of ranking and the affirmation of his contribution to mathematics, I believe that any other mathematician will express envy.

It's just that Xu Yun made the opposite decision from others.

"Thank you, Professor Deligne, for your affirmation of me, but I have joined the Institute for Advanced Study in Mathematics at Kyoto University, so I can only say sorry."

To put it mildly, he proved two mathematical problems that he did not need to join the Institute for Advanced Study in Princeton.

For him, what he should do more is to use his mathematical knowledge to cultivate excellent new mathematical forces.

He believes he can grow the Institute for Advanced Study in Mathematics to the level of the Institute for Advanced Study in Princeton.

And that day is definitely not far away.

Some of the students next to him, including Wei, were all surprised when they heard Xu Yun's answer.

I can't help but have a question mark in my mind.

He actually refused?

thought that he would not get the opportunity no matter what, but he was rejected by others.

I really answered that sentence.

People are more popular than dead people!

In this regard, Deligne was relatively calm, as if he had guessed Xu Yun's decision before throwing this question.

It's just that I didn't give up, so I tried.

"It's okay."

"No matter where you study mathematics, as long as you can contribute to the development of mathematics, it is enough."

"Thank you, Professor Deligne."

After listening to Professor Deligne's words, Xu Yun immediately nodded in response.

This is basically the end of the matter, and then Xu Yun only needs to wait to follow Princeton University to attend the mathematicians' conference, and the deadline for the mission is also close at hand.

But then Deligne threw out another request, and he couldn't refuse it.

(End of chapter)