For now, Zhang Yitang can be said to be the top mathematician in this field.

His work is recognized as a great achievement by international mathematicians.

This is evident from the British journal Nature calling his work an "important milestone".

Zhang Yitang's paper, Chen Zhou naturally studied it carefully.

He had never been shy about standing on the shoulders of giants.

In his opinion, this is how the inheritance of science should be.

"Professor Zhang, I have two small questions I would like to discuss with you. Chen Zhou thought of the content of Zhang Yitang's paper.

"You're welcome, you can say it. Zhang Yitang said with a smile.

When Chen Zhou heard this, he picked up a pen and wrote a line of equations on scratch paper: "It's about the result here." ”

Zhang Yitang took the scratch paper and glanced at it, his eyebrows couldn't help but tremble, this is the beginning of part 14 of his proud work.

【|k~K∑N(d1，k)|^2≤P1P2】

Looking at the equation on the scratch paper, Zhang Yitang asked softly: "You shouldn't have any problems with the derivation here, so you want to ask me, why did you come to this point?"

Chen Zhou nodded lightly: "That's right, the main thing is the key point." How to say it, I know it, I don't know why. ”

Zhang Yitang smiled, took the pen, and filled in the first few formulas in the paper.

【h￣(n2+hkr)≡￣l+kr(mod d1)......】

【(h，d1)=(n2+hkr，d1)=1，l≡￣hn2(mod d1)......】

【N(d1，k)=l(mod d1)(l+kr，d1)=1∑v(l;d1)n3?? N3′(n3，d1)=1∑ed1(b￣(l+kr)n3)......】

【v(l;d1)=￣hn2≡l(d1)∑′f(h/d1)......】

After writing, Zhang Yitang put the scratch paper on the table, pointed to the formula on it with a pen, and began to explain to Chen Zhou as a whole.

Chen Zhou listened extremely seriously, and at this moment he only felt that he had not come in vain.

The communication with Zhang Yitang alone has benefited him a lot.

"If you want to get to this point...... Zhang Yitang once again added the content of the formula to the scratch paper with a pen.

"The constraint of this ∑′ is 1≤h

"Referring to Eq. 13-16 in the paper, you should understand, right?"

Chen Zhou nodded: "So, this is the beginning of the derivation of the follow-up conclusion, but in fact, at this point, it will suddenly become clear." ”

Zhang Yitang had an appreciative look in his eyes: "That's right." ”

Chen Zhou looked at the scratch paper in front of him, and some thoughts rose in his heart.

Formulas are all spiritual.

After a pause, he asked again, "Professor Zhang, I have one more question." ”

Zhang Yitang thought about it for a while, and probably guessed what Chen Zhou wanted to ask.

He said directly: "In the study of the twin prime conjecture, you have to imagine that it is completely from nothing. Because we really don't know. It's like thinking that the universe is infinite and has no boundaries, only to find that it has an end somewhere. ”

This statement is kind of interesting......

Chen Zhou nodded lightly and waited for Zhang Yitang's words.

Zhang Yitang glanced at Chen Zhou and continued: "Imagine that there is a ruler that measures green and red numbers, we can use this ruler to move along the number axis and circle the two prime numbers countless times. ”

"But enclosing an infinitely many numbers doesn't necessarily mean enclosing all the numbers, because there are cases where an infinitely large number is even, but there are also infinitely many numbers that are odd. ”

By the same token, the ruler can move along the number axis an infinite number of times, but it can't circle two primes. ”

After Zhang Yitang finished speaking, he looked at Chen Zhou, who was in thought, silently picked up the coffee on the table and took a sip.

The waiter at the café breathed a sigh of relief when he saw that his coffee had finally been picked up and tasted.

Zhang Shouwu naturally heard what Zhang Yitang said just now.

It's just that for him, who has discussed with Zhang Yitang many times, he has heard these words at least three times.

After a long time, Chen Zhou said slowly: "So, you chose a ruler with a length of 70 million. ”

Zhang Yitang nodded: "Now this ruler has been shortened to 256." ”

Chen Zhou smiled, he only heard a hint of smugness now.

Indeed, after Zhang Yitang opened the door, countless mathematicians launched competitions.

But in a sense, these mathematicians are just "working" for Zhang Yitang.

Because Zhang Yitang himself is not interested in finding the minimum number of intervals.

He felt that this kind of work was purely a technical job, a kind of manual labor.

This is the difference between a pioneer and a successor.

It is also a rare smug look that Zhang Yitang showed at this time.

Chen Zhou suddenly thought of an interesting principle, as if a certain mathematician described Zhang Yitang's work.

He likened Zhang Yitang's work to the pigeon nest principle.

That is, let's say there are 70 million nests and an infinite number of pigeons, each representing a prime pair.

A pair of primes with a difference of 2, i.e. pigeons, are placed in a pigeon nest.

A pigeon with a difference of 3 is put into another nest.

And so on, all the pigeons with different intervals are put into one nest.

Finally, there will be a nest with an infinite number of pigeons.

But there is no way to know which nest it is, there are an infinite number of pigeons.

However, there is at least one nest with an infinite number of pigeons.

At this time, Zhang Yitang looked at the time and said to Chen Zhou: "I still have some other things, I have to leave first, and I look forward to your report meeting the day after tomorrow." ”

"Okay, you're busy first. Chen Zhou replied.

"This is leaving?" Zhang Shouwu said in a timely voice, "Don't you sit down more?"

Zhang Yitang smiled and said, "Isn't it the last time I released your pigeons? Next time I visit you in Princeton, right?"

Zhang Shouwu suddenly said: "This is what you said, I didn't force you, right?"

Zhang Yitang shook his head slightly: "I know, I know." ”

After Zhang Yitang left, Zhang Shouwu asked, "What about you, are you going to listen to the lecture again, or are you?"

Chen Zhou thought for a while and said, "I plan to go back to the hotel first." ”

Zhang Shouwu was slightly stunned, and then asked, "Have an idea?"

Chen Zhou hesitated and said, "It's very vague. ”

At the door of the café, Zhang Shouwu looked at the back of Chen Zhou's departure, and his mood was quite complicated.

Looking at the scratch paper with the formula written on it in his hand, his expression became strange.

"This kid, grab inspiration everywhere? Why didn't I hear what Lao Zhang said was inspiring?"

Walking on the way back to the hotel, Chen Zhou recalled Zhang Yitang's words just now.

For a moment, as he said, he seemed to have grasped something.

However, it's vague.

But he didn't want to let go of this vague thing easily.

Inspiration, if you release him once, he may release you for the rest of your life.

Back at the hotel, Chen Zhou turned on the computer.

The mouse's wheel is constantly sliding, with occasional clicks.

Chen Zhou is looking for Zhang Yitang's paper on the twin prime conjecture.

Papers, lying in the depths of a folder.

Double-click.

Open it.

Chen Zhou reorganized the content of the paper.