Coming out of Zhang Yitang's room, Pang Xuelin shook his head with a smile.

He could feel the flame that burned in the old mathematician's heart.

Perhaps because of this, Zhang Yitang was able to do such an excellent job after half a life of ups and downs.

And he vaguely felt that the reason why Zhang Yitang proposed the idea of an academic competition between the two sides was not to win himself.

After all, neither the familiarity with Ponzi geometry, nor the energy and thinking activity of both sides, are hardly on the same level.

He just hopes that he can set his sights on this field that he has been studying for many years, and that one day, the twin prime conjecture can be solved in his own hands.

……

In the following month, Pang Xuelin began to make presentations everywhere.

Stanford University, University of Chicago, University of Pennsylvania, Yale University, Harvard University......

During this period, in addition to using Ponzi geometry to find ideas to solve the twin prime conjecture, he kept brushing papers related to the twin prime conjecture.

It's just a pity that after a month, he still has no clue.

Math problems are like that, it doesn't mean you can solve them with the right tools.

Sometimes, inspiration is more important than skill.

It was not until Saturday, October 31, that Pang Xuelin arrived in Princeton.

In the real world, Pang Xuelin only came to Princeton to attend a few academic conferences when he was a student at ULCA, but in the rural teacher world, he lived in Princeton for a few months each year.

Therefore, Pang Xuelin is no stranger to this beautiful and quiet town.

Pang Xuelin's report at Princeton was scheduled for November 2, and after Pang Xuelin stayed at the hotel, he politely declined Drigne's invitation to dinner.

After thinking about it, he took out his mobile phone and sent a WeChat message to Qi Xin: "I'm coming to Princeton, are you free tonight?" Would you like to come out for a meal? ”

……

Princeton, a student apartment.

Qi Xin was holding his chin and looking at the photos on the computer desktop with some distraction.

This is a photo of her and Pang Xuelin at the Millennium Awards ceremony in Paris, France.

At that time, she was wearing an evening dress, and Pang Xuelin was in a suit and leather shoes, the two were handsome men and beautiful women, like a pair of beautiful people.

At that time, she thought that if she and Pang Xuelin went on like this, they might one day enter the palace of marriage.

didn't expect to make people happen, and in the end, the two still couldn't get together.

Qi Xin even regretted it a little, if he had been brave and confessed to Pang Xuelin earlier, maybe the one who was with him now would not be his childhood sweetheart, but himself.

Only now, regret is useless.

In the past six months, Qi Xin has worked hard to remove Pang Xuelin's figure from his mind.

But the more I try to forget, the more unforgettable it becomes.

She has been in Princeton for more than half a year, and with her appearance, there are not a few people who pursue her, including some of the opposite sex who are very good in terms of their own conditions and family background, but Qi Xin has no feelings for them.

She can only put all her energy on studying, using learning to consume her energy and prevent herself from thinking cranky.

But as long as Pang Xuelin's information appears on the Internet, she will still click on it involuntarily.

During this time, Pang Xuelin came to the United States to participate in the award ceremony of the Cole Algebra Award, and Qi Xin has been paying attention to the whole process.

Even after learning that Pang Xuelin was going to give a report meeting at Princeton, Qi Xin got a ticket for the report meeting early through his friends.

It's just that Qi Xin has been hesitating to contact Pang Xuelin.

Meet, eat, say hello, and then say goodbye, leaving sadness in vain?

Qi Xin shook her head, she was a little hesitant.

At this moment, there was a ding dong, and a message appeared on WeChat.

[I'm coming to Princeton, do you have time tonight, do you want to come out for dinner?] 】

As soon as he saw the sender's name, Qi Xin's heartbeat quickly accelerated, and a joy mixed with grievances and all kinds of indescribable complex emotions welled up in his heart.

Qi Xin picked up his phone and was about to reply, when a knock on the door suddenly sounded.

Qi Xin thought about it, got up and opened the door.

What appeared in front of her was a beautiful Asian woman who was not inferior to herself in any way, had a perfect figure, and had a little more mature charm than herself.

"Sister Zhi, why are you here?"

Qi Xin met Wang Zhi a month ago, only knowing that the other party was a third-generation Chinese, who had previously studied in the Department of Mathematics at Harvard, and because of the poor relationship with his supervisor, he transferred his studies to Princeton and became a graduate student of a professor of mathematics at Princeton.

Wang Zhi lives next door to her, maybe because they are both yellow-skinned, or because they fall in love with each other, after meeting several times, the relationship between the two quickly became familiar, and they faintly became good girlfriends who talked about everything.

Qi Xin even told Wang Zhi about his crush on Pang Xuelin.

As a result, Wang Zhihao laughed, saying that she had played a good hand of cards, and if she had been herself, she would have put Pang Xuelin into bed a long time ago.

Qi Xin just smiled at this, this Zhi sister has rich emotional experience, and she has a set of methods to flirt with men, after she came to Princeton, many teachers and students in Princeton were fascinated by her.

Wang Zhi entered the house with a big grin and said with a smile: "I heard that the male god you have a crush on is coming to Princeton, do you want to ask him out to play?" ”

"Huh?!"

Qi Xinqiao blushed and said, "No, I'm ...... I still won't bother him! ”

Wang Zhi blinked and said, "You shouldn't have already asked him out and want to avoid me on purpose, right?" ”

"Where...... How's that! ”

Qi Xin is a little confident.

"Then what are you doing hiding your phone?"

Wang Zhi grinned, suddenly flashed, got Qi Xin's mobile phone into his hand, clicked on WeChat and looked at it.

"I'm at Princeton, do you have time tonight, do you want to come out for dinner?" Oh, yes, he actually took the initiative to ask you out! Qi Xin, this is a great opportunity! ”

"What a great opportunity? Sister Zhi, give me back your phone! ”

Qi Xin pretended not to understand.

Wang Zhi smiled: "I'll help you reply, with your temperament, you want to go, and you can't let go of the girl's reserve on the surface, just like you, how can you snatch the male god!" ”

After that, she replied directly through WeChat: "Okay, at seven o'clock in the evening, Nassau Street, Witherspoon Steakhouse, see you or leave, and I'll bring a friend over at night!" ”

"Sister Zhi, how can you be like this, I'm really angry!"

Qi Xin stomped his feet.

Wang Zhi smiled: "Okay, Xiao Xinxin, don't be angry, hey, the phone will be returned to you!" ”

Qi Xin took the phone, looked at the reply, and said a little strangely: "Sister Zhi, are you going at night too?" ”

Wang Zhi smiled slightly and said: "I'm also a student of the Department of Mathematics, just to meet the legendary Pang Shen, don't worry, I won't rob your male god." You don't mind bringing a light bulb, do you? ”

Qi Xin glanced at her and said, "You have already replied, what else can I say." ”