Chapter 475: Shopping

Brazil, Rio de Janeiro.

Xu Qingzhou and Song Yao finished breakfast at the hotel restaurant and went straight to the convention center.

His first invited report session started at 9:00 AM.

Topic: The Laws of Prime Numbers.

Unlike previous report sessions dedicated to a specific conjecture, this time it was a summary; Xu Qingzhou shared the core content of everything from the Cramér conjecture to the Riemann hypothesis and made corresponding connections.

For example, the application of sieve methods, the coupling of various mathematical models, and possible connections between conjectures.

At the entrance of the convention center, the two separated.

Song Yao also had things to do.

As mentioned earlier, the conference had 21 subject areas, including algebra, number theory, geometry, topology, applied mathematics, etc. Each area was an independent group, and after that, each group arranged 10-12 invited reports.

Mathematics is the foundation of various disciplines, involving physics, biology, chemistry, etc., and economics is naturally included. Today, one of the breakout session themes was mathematical finance and game theory.

Specifically, it was optimal transport theory in mathematical finance; this theory is widely used in resource allocation models and market design in economics.

The reporter was the famous mathematician Alessio Figalli.

Next was the "Stochastic Analysis and Financial Mathematics" group report, which was roughly multiple scholars discussing the mathematical theory of financial risk measurement together.

The first four days passed in busyness, and time flew to August 5th.

The morning report topic was Birational Geometry and the Minimal Model Program.

The speaker was an Iranian-born mathematician from the UK, then a professor at Cambridge University, Caucher Birkar.

A hot candidate for the Fields Medal; if it weren't for Xu Qingzhou, this cheating genius, this genius mathematician's name would very likely have been on the Fields Medal list.

The other party solved the boundedness problem of Fano varieties, providing a unified framework for the classification of high-dimensional algebraic varieties, mainly sharing his research on the application of birational geometry in complex geometry and string theory.

Xu Qingzhou came out before Song Yao, waited at the entrance of the breakout session, and opened his notebook to look at the exchange notes from the past four days.

He waited for about 10 minutes, and a familiar faint fragrance drifted to his nose.

Xu Qingzhou raised his eyes; sure enough, it was Song Yao.

Except for the first day when she dressed up, Song Yao wore relatively casual clothes for the breakout session reports: a casual suit jacket over a T-shirt, paired with jeans, simple and natural.

Xu Qingzhou put away his notebook and stood up, "Let's go... back to change clothes."

"Why did you come out so fast?"

Song Yao took Xu Qingzhou's arm; she was originally going to find Xu Qingzhou at the main venue.

"Just a bit early..." Xu Qingzhou stopped, his expression strange, "Did you notice the chat content was a bit weird?"

Song Yao was stunned, but quickly reacted, straightened her face, and gave Xu Qingzhou a hit on the waist.

"No, you were clearly the one driving, why did you pinch me instead?"

"It's your thoughts that are dirty!"

"If you weren't dirty, how would you know what I was saying? Fine, fine, fine, I was wrong..."

The afternoon invited report was Algebra and Geometry, telling about the new correspondence between modular forms and elliptic curves. Other than that, there were some public lectures, and some roundtable forums, with the theme of the role of women in the field of mathematics.

Compared to these, Xu Qingzhou felt that accompanying Song Yao for her birthday was more important, and after being tired for 4 consecutive days, it was just right to relax.

The two planned to have lunch first, then go shopping at the mall, eat a good meal at a restaurant called "Autek" in the evening, and finally return to the hotel to eat cake and have a two-person world.

11:30 AM.

The two young people had already arrived at the Botafogo district, which was a gathering place for coffee-trading nobles in the 19th century, retaining a large number of neoclassical buildings, and now transformed into a modern community integrating commerce and art, considered a multicultural landmark of Rio.

In August, the Northern Hemisphere is in summer, while Rio is in winter. However, Rio's winter is different from Kyoto or Boston, with an average temperature of 21.8°C in August.

The rain had just stopped, the temperature had dropped sharply compared to yesterday, and there was a hint of chill in the air.

Fortunately, the two had packed thick clothes in their suitcases.

"Left hand in front."

Xu Qingzhou looked at the phone navigation and held Song Yao's hand to cross the road.

"Aren't these people cold?"

Song Yao's gaze swept over two girls in the distance wearing super short skirts; in such cold weather, exposing two legs...

She was freezing even wearing long pants.

"Foreigners' perception of seasons is a mystery," Xu Qingzhou said, having stayed abroad longer and long since gotten used to it.

In the past, when going out on days with heavy snow, he could see people wearing flip-flops and summer clothes.

He suddenly thought of something, squeezed Song Yao's hand and asked, "Do you want to buy a pair of 'bare-leg artifacts'?"

"The weather forecast says the sun will be out tomorrow," Song Yao said expressionlessly.

"You can keep them to wear later."

"No." Song Yao hummed, understanding this guy's thoughts: leg-fetishist, oh, no, this person also likes hands... so, he's basically just an old pervert.

"Fine..."

Xu Qingzhou nodded, paused, and said, "Silk stockings can also keep you warm, do you want to buy two pairs?"

"..."

Song Yao's "Kirin arm" couldn't be suppressed.

Annoying, there are more than a dozen pairs at home, isn't that enough to tear? And he still wants to buy... to eat?

The two crossed the intersection and followed the navigation to the restaurant.

Under Song Yao's threat, Xu Qingzhou chose to shut up.

On this side, Song Yao held Xu Qingzhou's hand and took a deep breath, really liking the feeling of the two of them walking leisurely.

Although Xu Qingzhou is annoying and always makes her angry, his hands are very warm, and walking on the road holding hands, just following him, without having to consider anything, there is an indescribable peace in her heart.

1:00 PM, the two finished lunch and prepared to go to the Una Creative Market in the district.

Before they arrived, Song Yao's phone rang; it was Zhang Junli's call, wishing her daughter a happy birthday.

"We are just about to go to the market... um, we will pay attention to safety..."

Song Yao replied.

To host this mathematics conference, Rio had rectified or strictly cracked down, and security measures had been improved a lot, especially in such tourist areas, so there wouldn't be much of a problem.

The main street is basically safe during the day, of course, there are also precautions, such as avoiding going deep into the northern hillside slum areas.

The weather was still a bit cloudy, the trees were moist, crystal clear water droplets gathered on the leaves, sliding down along the tree stems, and the leaves also jumped with inertia. The surrounding tourists were endless, and it was quite lively.

The wind coming towards them hit their faces, a bit stinging.

Xu Qingzhou stopped and helped the school beauty, who was on the phone, pull her collar together.

Song Yao raised her chin, making it convenient for Xu Qingzhou to help her zip up, while continuing to talk to Zhang Junli: "He and I both brought thick clothes..."

On this side, waiting for the green light, Xu Qingzhou held the soft little hand again.

After strolling around the market, the two entered a nearby commercial center.

(End of chapter) ===== CHAPTER 476 =====