Michael stared intently at the monitor screen.
“Is all of this actual road data?”
Lisa, MIT’s data engineer, pointed at the screen as she spoke.
“Yes. It’s a week’s worth of accumulated data. The model is receiving signals from the Department of Transportation sensors in real time and generating prediction routes on its own.”
On the screen, the city’s roads were slowly changing colors.
The red sections gradually shrank, and green spread all the way into the city center. The movement was so precise and natural that it looked as though they were watching the flow of real roads.
“It’s hard to believe this is an algorithm written by a person. How can it be this…”
Lisa nodded as if she understood.
“I know. I felt the same way. Seoha wrote all of this code himself.”
‘He wrote this much by himself? Does he not divide up the work?’
“That’s incredible.”
“There are parts we still don’t clearly understand. Just when we think we’re starting to catch up, he changes the code. It gets updated every week.”
“It looks perfect to me even now.”
Lisa shook her head.
“I thought the same thing last week, and the week before that. But every time Seoha updates the algorithm, the traffic flow improves noticeably.”
Michael was genuinely impressed.
“It’s amazing that such thinking is even possible. With large-scale models like this, people usually stop touching them once they’re stabilized.”
Did the word compromise simply not exist in his mind?
“I don’t think Seoha’s goal is stabilization. Even while updating it, he keeps the path open. Thanks to that, this system is evolving every day.”
Lisa looked over the code with an expression of awe.
Seoha’s algorithm was not linear like ordinary code. Every function influenced the others, interlocking with artistic precision.
‘How far does he have to go before he’s satisfied?’
“Huh?”
An accident occurred in the simulation. When the signal at the accident site stopped, five nearby traffic lights reacted all at once. The accident site was a mess, but its aftermath did not spread throughout the entire city.
Goosebumps rose on her skin.
It was as if an exceptional operator, whose brain was connected to the network, was coordinating the situation in real time.
‘If he ever had malicious intentions, how far could he ruin humanity?’
A mad scientist from some science fiction movie flashed through her mind.
“How has Seoha been lately?”
Lisa asked, looking at Jason.
He had been in the lab since morning, organizing supplies.
“He’s been spending more time with his eyes closed, deep in thought. Maybe it’s just me, but he seems to have become quite sensitive.”
Lisa nodded.
Any researcher went through such phases. She even felt relieved to know that this genius was no exception.
Another accident occurred in the simulation.
An exceptional situation.
The system tried to bring the chaos under control. But then another major accident occurred.
It was a chain collision. The city center became a complete mess.
“Huh?”
“What’s going on with this?”
A commotion broke out here and there.
Startled, Lisa stepped closer to the monitor.
Suddenly, the screen froze and flickered.
The city that had been turning green changed to gray in an instant.
Then warning windows appeared one after another.
[Simulation stopped.]
[Error : signal feedback undefined.]
“Stopped?”
“What happened?”
Lisa rapidly tapped on the keyboard.
“The sensor data is normal. There’s no problem with the network either.”
She zoomed in on the center of the city.
Red dots spread outward from the central intersection.
A few seconds later, all the lights on the surrounding roads went out.
The engineer in charge of the simulation stared at the screen with a hollow expression.
“R-responses have stopped across all sections.”
What on earth was this situation?
Lisa bit her lip.
The engineer opened the logs to try to get the situation under control. But he could not make sense of anything.
“This can’t be happening. We tested this version perfectly!”
Everyone fell into a panic at the unexpected error.
“What’s going on?”
Deputy Director Allen’s voice came from behind them.
As soon as he entered, he checked the status board.
“Lisa, prepare for a rollback immediately. To last week’s version.”
Lisa nodded.
With a major error like this, it was better not to even think about trying to fix it on the spot.
Clack clack clack.
“Loading the backup model.”
Just then, someone shouted urgently from behind.
“Wait!”
It was Seoha.
He must have run there in a hurry, because he was panting heavily.
His hands were covered in chalk dust.
“Deputy Director, if we roll it back now, we won’t be able to find the cause of the error. Please give me time.”
Allen quietly shook his head.
“Seoha, I want to do that too, but we don’t have time. If we can’t finalize the model by the end of this month, the Department of Transportation’s entire pilot schedule will be pushed back.”
His voice was firm.
But Seoha did not back down.
“Two days…”
“Hm?”
“Please give me just two days. If I can’t solve it by then, you can roll it back.”
Allen stared silently at Seoha. In his stubborn eyes, he saw a will that absolutely refused to give up.
He sighed, then nodded.
“I’m sorry for putting such a heavy burden on you.”
“No. Thank you.”
Seoha apologized to everyone, then hurried out of the office.
Thud.
Allen sank into a chair and wrapped his head in his hands.
There were more than one or two people whose necks were on the line for this project. The pressure made him feel like he was going to throw up.
“Deputy Director, shouldn’t we start ordering the equipment?”
All kinds of contracts and schedules were tangled together on the desk.
“I know, Tom.”
Signal controllers, data servers, and countless pieces of equipment and sensors were still waiting to be ordered, their specifications not yet finalized.
The firmware could only be written once the algorithm was finalized, so everything was completely halted.
The City of Boston still had not approved the budget needed for the project.
What was keeping them afloat for now was the budget they had secured last year and the Department of Transportation’s contingency funds.
The mayor was personally trying to persuade them, but the city council maintained its stance that “because the budget is so large, they would decide on support after seeing the pilot results.”
Bang!
Allen slammed the desk.
“Damn it. We need money to produce results! What kind of bullshit is this, saying they’ll give us the budget only after we show performance?”
In the initial plan, they had intended to give twelve weeks for algorithm development.
But now, they did not even have the luxury of waiting four weeks.
Allen felt miserable, as though he had done something terrible to Seoha.
It was a moment when he desperately thought of the cigarettes he had quit years ago.
* * *
Click.
As soon as Seoha returned to his office, he turned off the lights.
The silent lab sank into darkness. Only the faint glow of the monitor illuminated the desk.
The screen where the code had stopped was still on.
Rattle.
He opened a drawer and took out a chocolate bar.
If he was going to last two days, he needed to supply himself with fuel.
Thump, thump.
Seoha’s heart pounded violently.
He had already been pushing himself far too hard since last week. His weakened body was telling him to stop and rest.
Seoha felt a sense of responsibility.
The project that had begun as his assignment had now become a key city initiative. He knew the situation was difficult because the budget had not been approved.
‘I just have to finish it early.’
He steeled himself.
Click.
When he pressed the CD player, a winter piano performance began to flow out.
Handel’s Passacaglia.
The beautiful melody gently echoed through the lab.
His nerves, stretched taut, began to loosen.
Seoha closed his eyes and repeatedly exhaled, steadying his breathing. The cohabitant within him reached out a hand toward him. As if it were only natural, Seoha took his hand.
“Ducky! This isn’t the time to weigh this and that. Let’s start right away.”
He displayed the logs on the large screen.
Thousands of lines of code covered the screen. Ducky began analyzing the data that poured violently across it.
“It started in the city center.”
He murmured as if speaking to someone and enlarged the screen.
Intersection 17 within the frozen simulation.
He could see the flow of data severed as though a light bulb had gone out.
Seoha steadied his breathing and scrolled down the log window.
Numbers and symbols flowed endlessly across the screen. A system shutdown following a chain collision.
Intersections 17, 18, and 21 were referencing the same data at the same time. Each was waiting for the others to make a decision, holding one another back.
“A feedback loop…”
It was a phenomenon caused by the system’s synchronization becoming too precise.
Because the signals were meshed together too perfectly, the entire signal system had issued commands at the same timing. It could be resolved by adding a slight delay between the signals.
But Seoha did not like that.
If he compromised like that, the delay would spread in a chain reaction and eventually make the entire system sluggish.
In a city center, even a one-second signal delay could trap thousands of vehicles in congestion.
Seoha bit his lip and walked to the blackboard.
“Don’t make me laugh. I won’t make you slow. I’ll make you faster than anyone, but never let you stop.”
Seoha decided to overhaul the entire system.
Lines appeared in his mind.
One, two, hundreds and thousands of nodes were connected by lines, soon spreading out like a complex tree.
The complete logical structure of the algorithm was drawn inside his head.
The response time of each node, the direction of signal interference, the pressure distribution at intersections—soon, a massive structure composed of billions of nodes emerged.
In Seoha’s eyes, they were so clear he felt he could touch them with his hands. And he also came to understand the limits of this system.
“Was parallel computation too much for you?”
Scratch, scratch.
The chalk slid across the blackboard.
Seoha redesigned the functions from the ground up.
“Then I’ll give you a hierarchy. The lower levels will read patterns, and the upper levels will make decisions.”
Before long, formulas covered an entire blackboard.
But that was fine. This room had blackboards on three sides.
Equations and graphs tangled together chaotically. Yet in Seoha’s mind, a clear image of the completed structure had already settled into place.
A model that would not need to separate processing order even if hundreds of accidents occurred simultaneously, one that would not keep incoming data waiting but would process it through other layers.
The algorithm he was trying to design had gone far beyond simple parallel computation or automatic control.
Billions of nodes would react simultaneously while making judgments suited to their own situations. Each node had thousands of branch points, and each of those was connected to another lower layer.
It was a dangerously risky attempt where even a single error or delay could cause the entire system to collapse.
‘It’s okay. This is right.’
Ducky nodded as if he agreed.
“I’m not who I used to be, you know?”
Since coming to MIT, Seoha had grown at a rapid pace.
It was a situation anyone would call reckless and try to stop him from attempting. But Seoha’s hands did not hesitate.
Seoha’s unfathomable mathematical ability made it possible. At his fingertips, a system that had seemed impossible began to take form.
* * *
Two days later, Media Lab E14.
The air in the conference room was heavy. Each time the river wind struck the glass windows, the researchers shrank back for no reason, their shoulders flinching.
“Still no word?”
Lisa bit her nails, anxious.
Ellie sighed as she looked at her laptop screen.
“The connection is alive. But there are no logs at all of him accessing the main server. It looks like he’s been in that room alone the whole time.”
“For two days?”
“Yes.”
“The lights were on yesterday at dawn too. I saw his shadow when I passed through the hallway.”
The promised time was approaching.
Allen took out his phone, then put it back in.
Dozens of researchers were waiting for his decision.
“This won’t do. I’ll go see him myself.”
Allen rose from his seat and headed toward Seoha’s office.
The researchers, who were inwardly curious about the situation as well, all followed behind him.