After class, Lu spent about ten minutes to answer the questions raised by the students, whether simple or complex, and then put away the textbooks and left the classroom.

Standing up from the back seat, Perelman, who had been waiting for a long time, followed him out of the classroom and walked forward to follow the boat.

All the way, he said suddenly with a thoughtful expression on his face.

"A very common lesson."

Lu Zhou smiled and said casually, "it's a course for undergraduates. If it's too difficult, they may not understand it."

Perelman: why do you talk to undergraduates

Lu Zhou: "occasionally reviewing what is obvious why it is obvious helps us to think about what is not so obvious why it is not obvious In fact, this is Fermi's point of view. I agree with him very much. I'm not sure that there will be several winners of the fields prize among the students who have taken my courses in the future, which is much more successful than my own award. "

The expression on Perelman's face didn't change much.

For the awards in the field of mathematics, the pursuit of purity has always been his attitude of abandonment, so it is impossible to have any resonance when Lu Zhou said this.

But the first half of the sentence, it is to make him into a deep thought, mouth can not help muttering, this sentence chewed again.

“…… Not so obvious. "

"Yes," he said, nodding his head and chatting with the boat, "such as the dynamic theory and the Langlands program, these seemingly simple and easy to understand things actually explain the less obvious principles. What is the nature of numbers and shapes? Since the existence of mathematics, our civilization has been thinking about this problem. In history, great mathematicians are often theologians or philosophers. "

Perelman: are you a theologian

Lu Zhou: "it's a pity that I am a materialist who thinks death Here we are. This is my office. "

Take out the key and open the door. The boat turns on the light.

As usual, there are people on duty here, but today is Saturday, and his three assistants are off work at more than four o'clock. As for the students, since he never does the hard work of asking to punch in the office, he basically spends his weekends in the library or doing his own business.

"Help me get that whiteboard out of the corner."

"OK."

Walking forward, Perelman pulled the whiteboard out of the corner of the wall, and the boat pulled a marker out of the drawer of its desk.

Just when he came to the whiteboard and was about to answer the question of the friend who came from afar, there was a sound of footsteps outside the office. Another acquaintance knocked on the door and walked in.

"Academician Lu, I have come to visit you again. Are you Professor Perelman?" When he saw Perelman standing beside the boat with his arms in his arms, President Qin was shocked and his voice was incoherent.

Just after the meeting, he was going to talk to Lu Zhou about how to deal with it. Unexpectedly, he saw the great God in Lu Zhou's office.

Seeing this strange old man, Perelman hesitated a little, nodded his head and replied in standard English.

"Yes Any questions? "

"No, there is no problem, but we didn't expect you to visit suddenly," Qin yuan continued with a smile after controlling his excitement. "If only you would say hello to us in advance."

Perelman looked at him with a strange expression: "well I just came to talk to Professor Lu about some problems. Do I need to apply for a special application? "

"No, no, no, I don't mean that. There's a difference between greeting and applying, but we're ready for it. How to say... "

Looking at Qin yuan's embarrassed attempt to explain, Lu Zhou thought for a while and immediately understood his idea. He shook his head with a smile and said.

"Just give it to me here."

Relieved, the chief of the Qin court smiled and nodded, "please I'll talk to you later. You're busy first. "

With that, President Qin said goodbye, left the office and conveniently took the door.

As the latter part of the boat and the old man communicated in Chinese, Perelman didn't understand, so he looked at the boat and asked.

"What did you just say?"

"It's nothing, it's just a little trivial matter about work," Lu Zhou smiled, his thumb lifted the pen cover, and his eyes turned to the whiteboard. "We'd better continue."

……

Perelman is obviously well prepared to come to China this time.

From the small book he carried with him, it not only recorded some common Chinese Books marked with phonetic symbols and corresponding words, but also listed a lot of notes he made when studying the paper.

To be honest, it's not easy to answer Perelman's question, even for land boats. Many things he himself is studying, and only six or seven percent can give a clear answer.“…… Your question is very interesting, but I'm sorry that I can only answer these questions. The rest may not be able to answer you until the whole research is completed. "

"That's all right," said Perelman, closing his notebook and shaking his head. There was a trace of admiration on his expressionless face. "I was going to discuss these things with you, but I didn't expect you to know so much..."

Lu Zhou: "..."

I wipe.

You said it!

At first, he thought that this guy summed up these problems when he was looking at his paper, but he only guessed half of them correctly. These problems are really summed up when looking at their own papers, but they are not problems in their own papers at all.

The expression on his face didn't change much. Lu Zhou smiled and said modestly.

"I think you have studied the theory of grand unification. It's just that my research group is short of people I don't know if you're interested. "

At the time of saying this, Lu Zhou didn't have much hope. After all, this guy's temperament and temper are famous in mathematics.

What I didn't expect was that Perelman's reaction was unexpected again. Seeing that he didn't even think about it for a while, he said directly.

"If my job is necessary, please let me in."

Having said this, Perelman frowned at the fact that the boat had not spoken for half a day, and continued.

“…… Any questions? "

“…… It's nothing. It's just a bit of an accident. I didn't expect you to agree so readily. "

After returning to God from surprise, Lu Zhou was happy and said, "everyone's work is indispensable. With your help, I believe this building under construction will be more perfect In a word, welcome, now we are a comrade in arms in the trenches. "

With that, Lu Zhou turned and went back to his desk, and pulled out a document from the open drawer. After simply checking the contents above and making sure he didn't get it wrong, he handed the document to Perelman.

"Here is a document about the exchange of visits. It has already been stamped. Just sign your name. With this, you can change a new long-term visa at the immigration office."

"In addition, I guess you don't have a place to live. The new dormitory building of Jinling University happens to have an apartment with a pretty good environment. It's about 90 square meters. It's in the campus. It's close to the library or the experimental building of several institutes. I can help you apply for the identity of a visiting scholar. Similarly, you only need to sign this document. "

when listening to the series of arrangements thrown by the land boat, Perelman was stunned at first, then stopped him quickly, and said with a headache on his face:" Wait, what do visiting scholars mean? "

Lu Zhou: "literally, in short, I'm going to work as a distinguished professor in Jinling University. After all, you live in their dormitory."

Perelman frowned. "I don't want to work, I'm not interested in teaching. I'll leave here after I've completed the grand unified theory of algebra and geometry. If you can, just give me a sofa to sleep. There's no need to prepare an apartment for me. "

Lu zhoushook his head: "that's not good. Besides, even if it's a sofa, you have to have a place to put it."

Perelman shrugged and said, "I heard Schulz say you have a big family."

Lu Zhou coughed softly and said: "well Don't even think about that. No one has ever been able to spend the night in my house except my parents and my sister. "

Perelman: "..."

Looking at Perelman's silence, he seemed to be hesitating. "You don't have to worry about class. Even if you are a special Professor, it doesn't mean you have to have class. Of course, if you want to teach, I think those students who love mathematics will be grateful for your generosity, and there will be a large salary calculated according to the class hours. "

Perelman muttered, explaining, "I don't dislike teaching, I just don't want to waste my time on these unimportant things."

Lu Zhou: "so I didn't force you."

"Thank you."

"You're welcome," Lu Zhou smiled and held out his right hand. "It's my honor to be able to accomplish this great cause with you."

Holding the boat's hand, Perelman had a rare smile on his face.

But soon, he suddenly seemed to think of something, and his expression suddenly became a little embarrassed.

"I There's another request. I may have to trouble you. "

Release the hand, the boat smiled and nodded.

"You say, I can solve it for you."

Said Perelman with a light cough.

"The 90 square meter apartment is too big. Can you change it to a smaller one? It's about 20 square meters I'm not comfortable living in a spacious house in space. "Stunned for two seconds, Lu Zhou looked at him strangely, speechless and said: " I always thought you chose to live in that place because you were poor. "

Perelman stubbornly corrected the way.

"Poverty is just one reason."