Li Mu smiled, then straightened his face, and then continued: "Of course, I must also say that individual heroism cannot completely cover up the existence of collective heroism. ”

"The same is true of number theory."

"In the past, number theory was considered a beautiful but useless branch of mathematics, as a representative of individual heroism, and at that time, number theory seemed to become lonely."

"But now, with the introduction of the Langlands program, number theory is no longer solitary, but has begun to merge with other branches, and algebraic geometry, and group representation theory."

"From Gerd Faltings' use of algebraic geometry to prove the Modell conjecture, to Andrew Wiles's proof of Fermat's theorem from the Zenmeiya Mountain-Shimura conjecture, to the present, Li Mu has finally proved the Goldbach conjecture by combining K theory, modular forms and elliptic curves——"

"So, although number theory is still a representative of individual heroism in the mathematical community, it has also been integrated into collectivism."

"And what I mean by this is that I hope that you will continue to diverge your thinking in the following courses."

"In the future, number theory needs to be played in more fields."

"Even in the analysis of mechanics in physics, in the field of calculations in biology and chemistry......"

"So, then, I'm going to start with a question."

Li Mu turned his head and wrote a question on the blackboard.

Is there an infinite number of primes in the Fibonacci sequence? 】

Seeing this question, the students present began to think about it.

Fibonacci sequence, is there an infinite number of primes?

The Fibonacci sequence, also known as the golden section sequence, refers to the series of numbers such as [1, 1, 2, 3, 5, 8, 13......], starting from the third number, and each subsequent term is equal to the first two.

This sequence of numbers is magical, and it is even reflected in nature, such as the branches of trees, the petals of lilies, and so on.

Of course, for mathematicians who study number theory, they don't care how amazing this sequence is, they only care about this sequence, how many prime numbers there are.

This question is not very hot in the mathematical community, but it is by no means impossible, after all, it is another question related to quality.

"In the field of mathematics, we can't do without prime numbers, so in this problem related to prime numbers, I will gradually introduce to you the basic thinking of number theory, and some basic methods."

The students present were also interested, and the class started the class with an unsolved math problem, which was the first time for them.

In the past, their teachers would only mention the unsolved math problems at most, but they would not talk about them.

So, when interest is raised, it brings concentration.

And for Li Mu, this is also his purpose.

Interest is the best teacher, and in the process, concentration is also the most important.

当然，面对在场的一大堆数学菜鸟们，自然不可能一上来就展现出一大堆艰深的方法，这就意味着他得用入门级别的方法来对这种数学未解难题进行讲解。

If I were to change to most other math teachers, I would obviously have to say no to this kind of thing, because it is also a technical challenge for teachers.

But for Li Mu, it's not difficult.

And so, his teaching began.

在场的学生们，跟随着他的讲述，一边理解着这个问题的困难所在，一边也在不知不觉中吸纳到了数论方面的基础知识。

I don't know when, at the back door of the classroom, a few people came in.

These were all mathematics professors and teachers at Merton College, including Andrew Wiles and Lucas Licht.

They didn't come because this was Li Mu's class, but after hearing about what had just happened, they rushed here after hearing the news.

Seeing the crowded students, several people couldn't help but sigh.

“真不愧是这小子啊，这么多学生都来听他的课，有我当年的风范了。” Wiles said with a smile.

Licht did not refute his remark, because Wiles's remark was really not bragging.

In the period after he proved Fermat's theorem, there were almost so many students who came to listen to his lectures.

"Let's not talk about this kind of thing, don't you think Li Mu's way of lecturing is very special?"

Licht said.

Wilesmo rubbed his chin for a moment, and then nodded: "It's really special, he actually started with this question, and it gave people a feeling as if he was ......"

"Show off." Licht made a precise assessment.

Wiles was stunned for a moment, and then nodded repeatedly: "Indeed, it's just showing off your skills." ”

Of course, when they say showmanship, they are not showing off their mathematical ability, but showing off their teaching methods.

The flaunting skills of teaching methods refer to the kind of teaching methods that are technically difficult, but also very effective.

Just like now, Li Mu started with an unsolved mathematical problem, and first filled the interest of these students.

Of course, in general, when these students find themselves unable to understand the problem, their interest immediately falls into a trough.

But Li Mu can use some simple methods to help them understand.

In this way, these professors and teachers were also attracted by Li Mu's explanation, until when they finally came back to their senses, Li Het was suddenly surprised: "All these things he talked about can be written into a paper, right?" ”

"Like...... It really can. ”

Wiles was silent for a moment, and then couldn't help but speak.

Isn't this kind of lecture a bit too extravagant......?

Of course, if they knew how extravagant Li Mu was when interviewing graduate students, they probably wouldn't be puzzled by Li Mu's way of lecturing.

For Li Mu, this is not a luxury at all.

……

On the podium, Li Mu had actually noticed Wiles and them a long time ago, but this did not interrupt his class.

And in the process of lecturing, he also gave full play to his ability to multitask, thinking about what he said at the beginning.

Number theory, applications in other fields.

In addition, there is the problem that he has been thinking about, which is also the analysis of fluid mechanics.

With Lee's space to solve the external problem, but he has been lacking, another tool to solve the problem of the unity of the fluid.

As he said before the beginning, to think differently, at this time, he is thinking in a divergent way.

Number theory is helpful for the study of statistical physics, and there is also a relationship between fluid mechanics and statistical physics.

Starting from statistical physics, the direction of deriving fluid mechanics is a niche direction, and one of the most famous is to derive the fluid equation from the Boltzmann equation.

Suddenly, Li Mu's mind suddenly calmed.

He got it!

It's the Boltzmann equation!

The key puzzle piece was found by him!

It's just that the current Boltzmann equation is not abstract enough, and this piece of the puzzle still needs to be trimmed.

He needed to make it more abstract and generalize the different forms inside the fluid.

In this way, he can solve the final problem of the NS equation more perfectly.

And this, it is necessary to think more divergently.

Li Mu fell into a short thought.

And his brief thinking also made the class stop for a short time.

The students present couldn't help but be stunned.

They were listening so infatuated, why did they stop?

They even felt that under Li Mu's narration, they all had to know which direction to prove whether the Fibonacci sequence had infinitely many primes.

And the pause now is like a video broadcast at a critical moment, and suddenly it starts to buffer, making them anxious.

However, this pause did not last long, and Li Mu's narration began again.

Although the students present were a little puzzled, they quickly forgot about this pause, continued to follow Li Mu's narration and thought, and returned to their interest in this number theory class.

They probably never knew that Li Mu's brief pause would leave a deep imprint on the entire mathematical community and the classical physics community.

……

(End of chapter)