78: Bringing his wife and children to Harbin Institute of Technology

An'an's fever subsided the next morning.

Ye Bingwen stayed at the hospital all night, barely sleeping. Zheng Shuyun told him to rest, but he shook his head, saying he had to go to school today.

When I arrived at the mathematics department building, Ma Kui was already waiting at the entrance.

"I thought you weren't coming." Ma Kui handed him a steamed bun.

"Thank you, Teacher Ma." Ye Bingwen finished his meal in a few bites.

"Today we're attending Professor Chen Shou-chou's 'Introduction to Functional Analysis,' a graduate-level course," Ma Kui instructed as they walked. "Professor Chen has a quirky temper, so just listen to the lecture and don't say anything more."

Ye Bingwen nodded.

The classroom was filled with graduate students and senior undergraduates. Ye Bingwen found a corner to sit down and opened his Russian lecture notes.

Harbin Institute of Technology was heavily influenced by the Soviet Union, and many of its older professors were accustomed to using Russian textbooks. His Russian proficiency was average, but his mathematical formulas were universally applicable.

The school bell rang, and a gaunt old man walked onto the podium. His hair was gray, and he wore a faded Zhongshan suit, but his eyes were as sharp as an eagle's.

"Today we'll talk about linear operators on Banach spaces." Professor Chen spoke quickly and wrote rapidly on the blackboard, filling seven or eight blackboards in one class.

In the classroom, some people were writing furiously, some were frowning and struggling to keep up, and some simply gave up.

Ye Bingwen listened attentively. In his previous life, he had specifically studied this course to conduct research in control theory. Professor Chen's teaching style focused on theoretical derivation, which differed from the application direction he had learned in his previous life, but the underlying logic remained the same.

During the break, Professor Chen suddenly walked up to him.

"Are you new here? I've never seen you before."

"Hello Professor Chen, I am a freshman in the Department of Mechanical Engineering, here to audit the class."

The classroom fell silent for a moment, and several graduate students cast surprised glances at them.

A freshman attends a graduate student's class?

"A freshman in the Mechanical Engineering department?" Professor Chen frowned. "Do you understand?"

I understood most of it.

"Most of it?" Professor Chen pointed to a derivation on the blackboard. "Then tell me, what theorem is used in this step?"

Ye Bingwen stood up, walked to the blackboard, and picked up the chalk.

"A corollary of the Hahn-Banach theorem." He wrote down several formulas, "The extension properties of continuous linear functionals in normed linear spaces."

Professor Chen paused for two seconds, then smiled.

"That's right. What's your name?"

"Ye Bingwen".

"Ye Bingwen..." Professor Chen murmured, "I'll remember you. You can come to my classes from now on."

The surrounding graduate students exchanged bewildered glances. Professor Chen was known for his eccentric temperament and never praised anyone; why was he saying "not bad" to a freshman who was auditing the class?

In the afternoon, the Mechanical Engineering Department held a course on "Mechanical Vibration," taught by Professor Zhang Guangyuan.

Ye Bingwen arrived at the classroom early, and Cai Xun was waiting at the door.

"Did Professor Chen praise you this morning?" Cai Xun asked with a smile.

"I just said 'not bad'," Ye Bingwen said modestly.

"Chen Shou-chou is the apple of the math department's eye. Getting a 'good' from him is harder than winning a scholarship." Cai Xun patted him on the shoulder. "Go on in, Professor Zhang is waiting for you."

Zhang Guangyuan, in his early fifties, studied in the Soviet Union in his early years and is a top expert in structural mechanics of aero-engines in China. He glanced at Ye Bingwen and said in a cool tone, "You're the one who scored 493? Good grades don't mean everything. Sit down and listen to the lecture."

Ye Bingwen didn't pay any attention and found a seat.

After class, Zhang Guangyuan stopped him and pulled a piece of paper out of his lesson plan.

"Director Cai said you're very capable, I'd like to see. This is an exam question I took when I was studying in the Soviet Union, give it a try."

Ye Bingwen took the paper, glanced at it, and wrote down the modal analysis of a two-degree-of-freedom vibration system. He picked up his pen and finished writing in less than ten minutes.

Zhang Guangyuan took the paper, his expression changing from calm to surprise.

"Have you studied mechanical vibration?"

"I've read some books."

Zhang Guangyuan clearly didn't believe it, but didn't press the matter. "Alright, you'll come to class tomorrow too."

The next morning, Principal Liu Deben's test arrived as scheduled.

There were only four people in the small conference room of the school office: Liu Deben, Cai Xun, Ma Kui, and Ye Bingwen.

Two test papers were laid out in front of Liu Deben, five questions each in mathematics and mechanics, which he had personally prepared.

"Three hours. Let's begin."

Ye Bingwen opened the math paper, and the first question was the proof of Alaoglu's theorem in Banach spaces. He wrote down his thoughts almost without pausing.

An hour and a half later, he finished the math paper. He turned to the mechanical paper and continued writing.

Two and a half hours later, he put down his pen.

"Principal Liu, I'm done."

Liu Deben picked up the test paper and looked at each question one by one. The meeting room was so quiet that you could hear the ticking of the clock on the wall.

Ten minutes later, Liu Deben put down the exam paper and said expressionlessly, "Ye Bingwen, go outside and wait for a moment."

Ye Bingwen got up and left, closing the door behind him.

In the conference room, Liu Deben looked at Cai Xun and Ma Kui.

"All five math questions were answered correctly, and all five mechanical questions were answered correctly."

Both of them breathed a sigh of relief.

"But..." Liu Deben changed the subject, pointing to the last question on the math paper, "He used an unconventional solution to this question, one I've never seen before."

Ma Kui leaned closer to look, his expression changing as well. "This isn't standard proof..."

"But the result is correct, and it's much simpler than the standard proof." Liu Deben looked up. "Ye Bingwen's knowledge far exceeds high school level. Where did he learn all that?"

Ma Kui hesitated for a moment, "Perhaps... he's a self-taught genius?"

"A genius?" Liu Deben shook his head. "Even a genius couldn't possibly master graduate-level mathematics at the age of 21."

Cai Xun quickly said, "Principal Liu, no matter where his knowledge comes from, he is now our student. We should consider how to make good use of his talents."

Liu Deben remained silent for a moment, then nodded.

"Let him in."

Ye Bingwen re-entered the conference room.

"You've passed the test," Liu Deben said bluntly. "I agree to let you study both mechanical engineering and mathematics simultaneously. Your student status will be in the mechanical engineering department, and the mathematics department will issue you an 'honors auditor' certificate. When you graduate, having completed the required credits for both majors, I will issue you two degree certificates."

"Thank you, Principal Liu!"

"Don't thank me yet," Liu Deben waved his hand. "Three conditions. First, major in mechanical engineering; mathematics can't interfere with your main studies. Second, graduate on time. Third..."

He looked into Ye Bingwen's eyes and spoke slowly and deliberately.

"After you complete your studies, use your knowledge to contribute to the country."

Ye Bingwen nodded solemnly. "I promise you."

After leaving the school office, Cai Xun and Ma Kui both breathed a sigh of relief.

"A double degree, the first of its kind since the founding of Harbin Institute of Technology," Cai Xun said with a smile.

"The pressure is also great, with more than 40 class hours per week for the two majors combined," Ma Kui said.

"I can handle it." Ye Bingwen smiled, then suddenly remembered something, "Oh right, Shuyun is reporting to the publicity department today."

"Go on, don't keep your wife waiting." Ma Kui waved his hand.

When Ye Bingwen arrived at the publicity department, Zheng Shuyun had already been waiting at the door for a while. She had changed into a clean white shirt, and her hair was styled into two braids, looking neat and tidy.