Chapter 453

The next day.

Xu Qingzhou, who was lingering in bed, was grabbed by Song Yao and went out at 8:30 AM sharp. The morning report meeting started at 9 AM, and he was still the main speaker, 90 minutes.

The afternoon was group exchange.

Three days of report meetings passed like this.

On the morning of the 23rd, Xu Qingzhou sent Chu Jiangfeng and his party to the plane and went straight to the MIT library. Song Yao went out early in the morning. It was better to be in the library than alone at home.

Reading books and checking materials all required a good atmosphere.

Although there was only the little waste Er Miao at home, it wasn't noisy, especially during the day, this guy basically had no energy and liked to lie down and sleep most of the time, but it still didn't feel like the library.

Before returning to Xia Nation, Xu Qingzhou wanted to organize the notes from the report meeting first. By the way, there was also the report meeting at Jingda.

Kyoto's report meeting would last for two days, and he could directly use the content of this report meeting, only needing to change some details that had been perfected in the past three days.

Early morning, the sun was bright, but not as scorching as at noon. It was the most comfortable time. The shade was covered, and the wind blowing from the south carried the smell of water algae from the Charles River.

The report meeting ended, the big shots in the mathematical world left, and MIT returned to its usual peace.

"Professor Xu."

"Good morning."

Xu Qingzhou nodded and greeted the students who said hello around him.

Listening to everyone's address to him, he was a bit dazed. In the past... it seemed he could often hear students calling him "Professor Xu."

The difference was that it took more than ten years to get this title in the past.

It was still quite intimate.

Reborn until now, four years passed in a flash...

Xu Qingzhou found an empty seat in the library and sat down. His gaze passed through the window and fell on the two children playing on the lawn. That sense of unreality appeared again.

He started to be unable to tell if there was really a previous life. Perhaps, everything in the past was his own fabrication.

"Or, the person I am now is actually lying in the ICU, and everything here is a dream."

Thinking of this, Xu Qingzhou himself laughed.

Buzz~

The phone on the table vibrated. He opened it and saw Song Yao's message.

Song Yao: "Go for a run in the afternoon."

Xu Qingzhou: "Any other options?"

Tired for a few days, he really wanted to sweat, but he just liked to be cheeky when sending messages.

Song Yao: "Yes."

Huh?

Doesn't fit School Beauty Song's persona.

Xu Qingzhou stared at the phone screen without moving.

Ding~

Messages really popped up behind Song Yao's avatar.

Song Yao: "You can choose where to be buried."

Trembling with anger.

The husband's authority is not strong.

Xu Qingzhou carried the condemnation of School Beauty Song's violence and gritted his teeth to type: "I choose to run."

Song Yao: "Smart (hug)."

Xu Qingzhou: "..."

Those who know the times are heroes.

After sending the message, Xu Qingzhou leaned back and thought: "Forget it, I'm awake now. This world must be real. After all, there are still tooth marks on the shoulder bitten by School Beauty Song last night."

He shook his head, his gaze falling on the notes in front of him.

In these three days of exchange meetings, Xu Qingzhou gained a lot.

For example, meeting mathematician Katalin Harrigan.

The book *Singularity Theory of Minimal Models* he read before was written by her.

The old lady was over sixty, but her spirit was quite strong. During the exchange process, she was humble and rigorous. The two calculated on the spot, wanting to verify whether there was a certain duality between the poles of the Riemann zeta function and the singularities of algebraic varieties.

Of course, there were no results.

Can only look forward to follow-up research.

In addition, he also explored the deep connection between the Riemann Hypothesis and geometric structures with the new-generation geometer Pierre from the perspective of Grothendieck's "anabelian geometry," looking for whether there was a geometric expression.

He also discussed the optimization of complex analysis with Tao Zhexuan, and finally discussed quantum algorithms with physicist Witten.

And there was indeed a distinct contrast between foreign countries and Xia Nation in the form of academic exchange.

No complicated rituals, entering the topic in a few minutes, taking academic efficiency as the core, and omitting redundant links.

Moreover, everyone who came this time could be said to be a big shot.

No choice, the Riemann Hypothesis was just too important.

In the field of mathematics, there were not only the Riemann Hypothesis among the conjectures that hadn't been solved for more than half a century, such as Fermat's Last Theorem, which had troubled people for three and a half centuries, and the Goldbach Conjecture, which had been proposed for more than two and a half centuries, but it was still unresolved.

The history of the Riemann Hypothesis seemed short compared to them.

But if we talk about the connection with other mathematical propositions, and even various disciplines in the field of physics, the Riemann Hypothesis could be said to be far ahead.

Once the conjecture was established, all propositions relying on the distribution of zeros in the conjecture, the optimization of the error term of the Prime Number Theorem, and the error term of the prime density asymptotic to (1/lnx) could be greatly improved, for example, compressing from (o(x^{1/2+\epsilon})) to (o(x^{1/2}lnx)).

In addition, there was prime interval estimation, all of which would automatically hold.

In terms of examples, it was related to cryptography. Modern public-key encryption (such as RSA) relied on the difficulty of large prime factorization, and after the Riemann Hypothesis was proved, the deterministic law of prime distribution might give birth to more efficient prime generation or factorization algorithms.

In short, Xu Qingzhou was indeed busy these few days, but he gained a lot.

Interestingly, in the conference, the zero-capture tool he used in the process of proving the Riemann Hypothesis became the "Xu Capture," and the way of innovatively introducing physical tools was the "Xu Transformation."

"Get to work."

Xu Qingzhou withdrew his thoughts, picked up his pen, and continued yesterday's calculation, currently considering the application of the Riemann Theorem in integers.

"Let w(n) be the number of different prime factors of a positive integer n. In particular, w(1)=0. Let fk(n)=1, w(n)=k, 0, w(n)≠k, so a prime distribution function can be defined."

In June, the weather in Kyoto and Boston was actually not much different.

Yandongyuan.

"Finally back."

Xu Qingzhou pushed two large suitcases into the door.

The air carried the smell of dust. For a year, except for Auntie Jia, the landlady, coming over to check the water and electricity and ventilate the house, it was completely idle at other times.

Song Yao carried a white backpack.

Xu Qingzhou wiped out two stools with paper and sat down. After resting, he turned his head to look at the beautiful School Beauty Song beside him: "I think you should take the suitcase, I'll carry the bag."

"I'm a girl, my strength is small."

Song Yao curled her lips, turning around to check the situation in the room.

"..."

Xu Qingzhou was speechless. School Beauty Song liked to pretend to be a weak girl; this might be what you lack, you want to pretend to be.

"Don't sit, clean up."

Song Yao put down her backpack and went to get a broom and a towel.

"Alrighty~"

Xu Qingzhou first took the cotton wadding in the vacuum bag to the balcony to dry, and swept the floor with a mop.

Song Yao tidied up the bedroom and took out the bed sheets brought by the suitcase.

The two were busy all morning, cleaning inside and out. Although they were quite tired, living in a familiar place was always better than going to a hotel.

After a simple nap at noon, Xu Qingzhou carried gifts to Professor Gu Zhizhong's side, and Song Yao also took things to Li Daiyue's side.

(End of chapter)