Translator: Dreamscribe
“Oppa, why is the sky blue?”
Seo-eun asked as she looked up at the sky from the yard.
“Sunlight actually has all the colors of the rainbow mixed together. But when it passes through the sky, blue scatters the most, so it looks blue to our eyes.”
Six-year-old Seo-eun had reached a stage of development typical for children her age.
The so-called ‘Why stage’.
As the name suggested, she constantly asked questions. But Yu Seo-ha never hesitated with his answers.
“Then where did the other colors go?”
Seo-eun brought her index finger to her slightly open lips.
That sight was so lovely that Seo-ha patted his little sister on the head.
“Red or yellow light comes straight through and reaches us directly. That’s why the sun sometimes looks red, right?”
“Ah! I get it now.”
Clapping her hands in delight, Seo-eun runs around the yard.
Seo-eun loved her oppa more than anyone in the world.
No matter how many dozens of questions she asked every day, Seo-ha never answered with “I don’t know.”
A caring oppa who knew everything.
Whenever he was out of the house, Seo-eun would secretly sneak into Seo-ha’s room to play.
Mi-young, knowing how sensitive Seo-ha was, warned her daughter, saying “You can’t go in there until your oppa gets back!” but it was useless for Seo-eun.
Creak.
The door opened slowly, and Seo-eun glanced around before poking her small face through the crack.
‘Mom’s in the vegetable garden.’
Seo-eun tiptoed in and quietly entered the room. Then she plopped down in front of the bookshelf that filled one wall.
There were so many books that her neck hurt just looking up.
“Animal encyclopedia is... here!”
Seo-eun pulled over a chair and took out a thick book.
Sometimes, while reading the encyclopedia, she would come across notes her oppa had written in pencil. Seo-eun searched for them one by one like a treasure hunt.
“Yesterday I saw desert animals, so today it’s sea animals... sea... sea...”
Seo-eun flipped through the pages with her small hands. Then she found what she was looking for.
“Here it is!”
Oppa’s handwriting.
[Penguins actually have knees. They’re just hidden under their feathers.]
[Whales are mammals, so they feed milk to their babies.]
[Octopuses have three hearts.]
“Huh? Three hearts?”
Uncomfortable from sitting, Seo-eun lay on her stomach on the floor and turned the pages. Tracing her oppa’s handwriting with her finger.
There were also lots of notes in the math encyclopedia, but they were full of numbers and symbols Seo-eun couldn’t read, so she quickly lost interest.
The next day, Seo-eun was again playing on the floor in her oppa’s room.
Bored, she rolled her body toward the drawer. Then she remembered her oppa storing something there before.
Click.
When she opened it, there was a notebook deep inside she had never seen before.
“What’s this?”
Seo-eun tilted her head and pulled out the notebook. There was nothing written on the cover.
“Waa!”
Turning the first page, Seo-eun’s eyes widened in amazement.
It was a drawing by her oppa.
The entire page was filled with a man wearing a duck mask. With only the lower half of his face showing, like Batman, he looked like a cartoon character she had seen somewhere before.
Though drawn in pencil and black-and-white, the mask was colored yellow. Around the man floated mysterious mathematical formulas.
Intrigued, Seo-eun looked closely at the drawing.
The man somehow looked scary but also felt familiar. After all, he was wearing the duck mask both Seo-eun and her oppa loved.
“When oppa comes back, I’ll ask him to play mask game with me.”
Seo-eun carefully put the notebook back where it was. Then she hugged the duck plushie her oppa had given her and went outside.
***
“Time’s up! Please put down your pencils.”
With the proctor’s announcement, the first day of the competition, a long 4 hours and 30 minutes, came to an end.
The sound of pencils being put down echoed throughout the exam hall. But there wasn’t a hint of relief on the students’ faces. Rather, a heavy and despairing atmosphere took over the room.
Students submitted their answer sheets and stood up. Shock and confusion were clearly written across most of their faces. Some students still had their heads in their hands, unable to get up, while others stared blankly at the ceiling.
“What is this.”
“These are completely different from past problems!”
“Are these even real questions? That was way too hard.”
Murmurs could be heard from all around.
“Haa, haa....”
Lu Yichen panted heavily.
It had been a long time since he last ran out of time while solving problems.
He spent two whole hours on just problem number 1.
Wasting time early on due to a wrong approach had been fatal. Normally, a number theory problem like this wouldn’t take more than 30 minutes at most.
The core of the problem wasn’t number theory.
None of the usual approaches worked at all. Factoring, modular arithmetic, Diophantine equations (*indeterminate polynomial equations that seek only integer solutions), he had tried every method he was familiar with, but couldn’t even find a clue.
It wasn’t until the word “give up” began to flicker in his mind that he finally realized the problem required an approach based on algebraic number theory.
‘It’s too late, though.’
Perhaps because he was pressed for time, he wasn’t able to properly showcase his strength in geometry problems.
He barely found the answer and was midway through solving problem 3 when time was up.
Lu Yichen looked around.
Most people hadn’t even solved problems 1 and 2, let alone problem 3.
‘Are they trying to hold China in check?’
Maybe the problem was that China had done too well last year.
When the problems are too difficult, it can actually reduce the ability to distinguish top scorers.
‘Not even close.’
Lu Yichen was confident he could do better than anyone here, no matter what kind of problems were given.
It was a confidence born of having the greatest talent and working harder than anyone else, that was Lu Yichen.
“Lu Yichen, how did it go?”
One of his teammates cautiously asked.
“....”
Lu Yichen didn’t answer.
“I barely got through problem 1. And even that I’m not sure about.”
“I didn’t even look at problem 3.”
The team members gathered one by one and began to share their thoughts.
It was worse than they had expected, a disastrous performance.
‘Does this mean the attempt to hold China back worked?’
They were gifted students handpicked from across China, but they had not broken free from the limitations of rote learning.
But that was the same in every country.
In the end, Lu Yichen figured it would all be fine if he took the top score himself.
“Why are they laughing?”
One team member pointed toward the Korean team’s section.
“That was insanely hard.”
“But the principle Seo-ha talked about came up, so I think I got that one right.”
“The study group really helped a lot, didn’t it?”
“Considering how difficult it was, I think I did fairly well.”
The Koreans were chatting in words he couldn’t understand.
But something about the slightly excited tone of their voices made Lu Yichen uneasy.
Do-kyung hugged Seo-ha and patted his back.
If the Korean team’s level was what Lu Yichen knew it to be, it would be hard for them to get a good result. But it was clear they hadn’t completely failed the test either.
“Let’s go.”
In any case, everyone had faced the same conditions.
Today, he had failed to manage his time because he misunderstood the nature of the questions. But there was still one day left.
***
“Seo-ha!”
Su-jeong called out to Seo-ha, who was walking ahead.
Seo-ha naturally slowed his pace to match hers.
Su-jeong looked cheerful.
“Seems like you did well on the test?”
She almost asked, as usual, “What about you?” but stopped herself. Seo-ha was simply on a different level.
“It’s thanks to you. If it were the old me, I would’ve given up on problem 1. Do you remember? When we first met.”
“Ah! That time?”
As if remembering something and Seo-ha chuckled as he looked at Su-jeong’s face.
Since it wasn’t a particularly beautiful memory, Su-jeong’s face turned red.
“N-not that! I mean, I asked you about a proof after the test, remember?”
“Of course I remember.”
“Since then, I’ve felt myself improving. No matter what problem I face, I try to look at it from a different perspective.”
“I like that about you, noona.”
“W-what?”
Su-jeong was startled.
“Noona is like the mathematicians of the past.
You wrestle with the problems alone to the very end, and even when you hit a dead end, you never give up. That day, when you kept focusing on one unsolved problem until the test ended, that’s how I saw you.”
Su-jeong, unable to hide her embarrassment at Seo-ha’s compliment, quickly changed the subject.
“Ah, you really like old mathematicians.”
As if it was a topic he was already deeply interested in, Seo-ha’s expression turned serious.
"I also think while looking at those people. To never give up."
Joseph Fourier devoted his entire life to proving the heat conduction equation, known today through Fourier analysis.
This equation was only completed after his death, by Dirichlet and Riemann, among others. A truly incredible display of persistence.
“Do you have problems you want to give up on too?”
From Su-jeong’s perspective, there was no theory Seo-ha couldn’t understand and no problem he couldn’t solve. If even he wanted to give up, what kind of problem could it possibly be?
“Of course I do. But I won’t give up.”
From Seo-ha’s demeanor, Su-jeong could tell he wasn’t going to share what he was struggling with.
‘When did he become so mature?’
Standing next to him, she realized they were already about the same height.
When they first met at last year’s competition, she had only thought of him as a little kid...
In the past, Su-jeong didn’t want to let anyone go ahead of her.
But now, just trying to keep up was so exhausting that she didn’t have room in her mind to think about anything else.
‘Soon, he might be out of sight.’
She didn’t know it herself, but perhaps Seo-ha was already far beyond reach.
A sudden wave of anxiety made her chest tighten.
“Noona, are you okay?”
“Yeah, I’m fine.”
Maybe she had underestimated it.
Following Seo-ha might be a far more remarkable task than she had thought, Su-jeong realized.
***
From early dawn, footsteps could be heard in the dorm hallway.
Students who had woken up earlier than usual (or perhaps hadn’t slept at all) moved quietly.
It was the second day, still under the shock of yesterday, and everyone was tense.
Perhaps from crying all night, Seo-ha saw the swollen eyes of a few students. He wasn’t the only one who had staked a lot on this competition.
Same seats, same desks as yesterday, but the atmosphere was completely different. Everyone’s nerves were on edge.
Finally, the proctor appeared with the test papers.
The final exam of the competition began.
Flap.
Seo-ha opened the test paper.
‘Hmm?’
As he scanned through the problems, the last one stood out as odd.
The answer wasn’t immediately obvious.
‘Oh-ho!’
Finally, a problem worth solving had come.
He could feel Ducky squirming, wanting to solve it himself.
‘No.’
Seo-ha gently suppressed Ducky.
Unable to resist his curiosity, he immediately began with problem 6.
It was a type of problem he had never seen before, but it felt strangely familiar. As if he had seen it somewhere.
‘Ah! Problem 6 from 1988!’
It was exactly the same feeling he had when he saw that problem.
A smile spread across Seo-ha’s face.
And soon, he completely immersed himself in his own world.