Chapter 15
“So… you're saying that Ms. Yoo A-yeon taught herself mathematics from Professor Shin I-jun’s research notebook and major textbooks, independently found a way to prove the Riemann Hypothesis by referring to the ideas in that notebook, and wrote that whole process up as a paper?”
“Yup! For the record, my muscles are still weak, so Mom helped me type. That’s why Mom is the second author.”
Professor Park looked at me again.
The look in his eyes had changed; he was testing me.
“Ms. A-yeon.”
“Yep.”
“Then let me ask just one more thing.”
Professor Park put the paper down and walked over to the blackboard on the wall.
He filled the board with equations using a marker, then asked me a question.
“This is a problem related to the distribution of special values of L-functions that I’ve been studying recently. How do you think I should approach it?”
I studied the equations on the board for a moment.
It was a problem dealing with L-functions in the context of the Langlands program.
A problem at the forefront of analytic number theory.
It didn’t completely overlap with my field, but there was enough of an intersection that I wasn’t totally in the dark about which direction to take.
“Hmm… please give me a little time to think.”
“Of course. Take as long as you need.”
I sank into deep thought.
As I thought hard, my feet started fidgeting unconsciously.
I paced around the lab in circles and even hopped in place.
Mom tried to stop me, but the professor said it was fine and told her to just watch.
A few minutes later.
After much agonizing, I answered carefully.
“…What if you use the correspondence between automorphic representations and Galois representations? Since the special values of L-functions are connected to motivic cohomology, I think you might be able to find a clue there… Of course, I could be wrong. It just seems like a direction worth trying.”
Silence.
Professor Park looked down at me silently.
“My God…”
Then he pressed his hand to the corner of his eye and said nothing for a while.
“Professor?”
I called out cautiously.
Professor Park raised his head.
By then, his expression had gone beyond disbelief and turned slightly resigned.
“Ms. Yoo A-yeon… are you really five years old?”
“Heheh. Technically, I’m five years and three months old!”
“…Honestly, at first I thought this was some kind of hidden-camera prank prepared by Han Seol-ae. We’re not even that close, so I wondered why you were suddenly doing this. But now I have to admit this is real. To have such a deep understanding of modern mathematics at age five…”
“Hehe. I am pretty amazing, aren’t I!”
I puffed out my chest with a smug expression.
“Ah, A-yeon!”
“It’s all right, Han Seol-ae.”
Professor Park Mu-yeol bent his knees to meet my eye level.
“Ms. Yoo A-yeon. Let me ask you one thing.”
“Ask me anything!”
“You said you got your inspiration from looking at Professor Shin I-jun’s research notes in the study, right?”
“Yup!”
“In your opinion… did that notebook have academic value? Was Professor Shin I-jun’s final research… not in vain?”
Professor Park said in a cautious voice.
I immediately understood the intent behind the question.
Professor Park Mu-yeol was also one of the people who mourned the death of Shin I-jun, a fellow researcher in the same field.
We are scholars.
Even when a scholar dies, the research records they leave behind remain.
Those records are passed on to the next generation, and the next generation builds upon them to create new research records.
And then to the next generation. And then to the next generation.
In that way, humanity has accumulated knowledge and advanced civilization.
We scholars are the ones who have been running an endless relay race, passing the baton called knowledge to the generations that follow.
A grueling race where you can’t even see the road ahead clearly.
Many have fallen without managing to pass the baton properly.
So, what Professor Park Mu-yeol wants to hear is this.
That the research Shin I-jun did in life, the records he left behind, properly passed the baton on to his successors.
I answered without hesitation.
“Of course!”
I spoke clearly and loudly to Professor Park.
“If not for that notebook, this paper wouldn’t exist! Professor Shin I-jun’s approach set my direction from the very beginning! And even that direction wouldn’t have been possible without the ideas mathematicians had accumulated over 160 years! So all I did was add one more brick to a well-built brick tower!”
That was not an exaggeration.
It was simply the facts as I felt them.
In fact, I lost some of my memories when I was reincarnated.
So I forgot exactly what I had done during the last three months of my previous life.
I reconstructed the proof process by reinterpreting that notebook.
If Shin I-jun’s research notebook hadn’t been in the study.
If there hadn’t been the memo Shin I-jun left in the cloud.
There would have been no way for me, Yoo A-yeon, to recover the lost proof process.
Therefore, the research notebook Shin I-jun had scrawled in a trance for three months
definitely had meaning.
It was properly passed on to a successor named Yoo A-yeon.
“So.”
I looked Professor Park straight in the eye and said,
“It wasn’t in vain. His research.”
The professor remained still for a moment, then slowly stood up.
Then he looked out the window.
Warm sunlight was pouring over the campus.
Professor Park Mu-yeol must have also come to my funeral in my past life.
What had he been thinking when he saw Shin I-jun’s funeral hall?
…Maybe I should have gone to my own funeral too?
The professor said, recalling the past.
“Professor Shin I-jun was an extraordinary rising star in the mathematics world. He achieved an impressive career at a young age and showed insights that even surprised me. I thought he might truly prove the Riemann Hypothesis. That’s why it was all the more heartbreaking. I never expected him to die so young from a heart attack.”
Then Professor Park turned his head and looked at me.
“But Ms. Yoo A-yeon, you carried on his legacy.”
Shin I-jun was dead.
But I had inherited his legacy.
I had completed the Riemann Hypothesis paper in keeping with his wishes.
“Thank you, Ms. Yoo A-yeon.”
“Heheh. It was nothing.”
At the middle-aged professor’s praise, I wriggled bashfully.
Professor Park returned to his desk and picked up the paper again.
“And I think I have a rough idea why you came to see me. I’ll read and review the paper properly. And if there are no issues, I’ll endorse it. I’ll also send recommendation emails to my fellow professors.”
“Yay—! Professor Park Mu-yeol—! Thank you so much—! Hehe!”
The moment I heard that, I got so excited I started hopping up and down right there.
“A-A-yeon! Hey!”
Mom tried to scold me, but—
“Hoho. It’s fine. A child should be running and playing like that. My daughter used to be like that too. These days she’s preparing for the college entrance exam, and she’s so sensitive and on edge…”
Professor Park stopped Mom, saying it was fine.
See? Professor Park really was kind!
Well, the reason I came to see him in the first place was because I knew he was a good person.
After wrapping up the conversation nicely,
“Then, bye-bye, Professor Park Mu-yeol—!”
“We’ll be going now. Thank you, Professor Park Mu-yeol.”
Bow-
Mom and I left the professor’s office.
✒️✒️✒️
Vroom-
After finishing our business, the four of us got back in the car and headed home.
Of course, since we were in Daejeon, we didn’t forget to stop by a famous local bakery!
We even bought loads of bread to give as gifts to acquaintances, so the car was filled with the savory smell of bread.
Since Arin and I still had baby teeth coming in, Mom cut the bread into small pieces and popped them into our mouths.
“Mmm-nyam nyam nyamu.”
“Ong-nyom nyom, hehe.”
Hehe.
The bread’s delicious.
“A-yeon, how was it? Talking with the professor. Munch munch.”
Dad asked me while driving with bread in his mouth.
“I was super nervous, but after doing whoosh-whoosh deep breaths, it went okay…”
“Really? You were that nervous? To me, it looked like you answered really well...”
“But I didn’t expect him to suddenly throw a problem he was researching at me… the distribution of special values of L-functions… that’s a hot topic in analytic number theory! Even my past-life self couldn’t answer that properly—it was an insanely hard problem!”
“Ah, that? I didn’t understand what you were talking about, but I remember how adorably you reacted. You suddenly propped your chin on your hand and thought hard, then busily wandered all over the place—”
“Aaaah! Mom, stop saying that, it’s embarrassing!”
Hearing our conversation, Arin laughed beside us.
Before long, sunset began spreading over the highway.
The orange light stretched along the horizon and colored the inside of the car.
Maybe because I had gotten so tense in front of the professor that my energy had been drained.
Exhausted, I quickly fell into a deep sleep.