Reunion in the sea of ​​people

When the ginkgo leaves at Peking University turned completely yellow, I spent the entire week in the physics lab. My supervisor's assignment on semiconductor material analysis was stuck on crucial data; the crystal lattice images under the electron microscope were always blurry, like a layer of impenetrable fog. When Jiang Yi knocked on the lab door, I was staring blankly at the chaotic curves on the computer screen, coffee stains from my fingertips staining my white lab coat, leaving a light brown mark.

"Still struggling with this data?" He was carrying two cups of hot cocoa, placing one in front of me. The warmth of the cup seeped through my fingertips, making them tingle. "I just came back from the archives and saw a similar research report from last year. It mentioned that the focusing angle of the electron beam needs to be finely adjusted by 0.5 degrees. Have you tried it?"

I looked up abruptly, my weariness instantly replaced by surprise: "0.5 degrees? I've been stuck around 0.3 degrees..."

"You'll know once you try." Jiang Yi smiled and pulled up a chair to sit down next to me. "I'm free tonight anyway, I'll keep you company."

As the microscope lens slowly rotated, the instant the electron beam swept across the sample surface, the crystal lattice on the screen suddenly became clear. The regular arrangement of atoms shimmered against the deep blue background like an exquisite tapestry. I was so excited that I almost knocked over my hot cocoa. Jiang Yi reached out to steady the cup, his smile brighter than the glowing dots on the screen: "Looks like we've found the right direction."

As we were recording data on the screen, the lab door was pushed open, and two boys wearing Tsinghua and Peking University physics department uniforms entered. One of them looked particularly familiar in profile under the corridor lights—it was Zheng Yiming.

He was taller than he had been six months ago, his hair cut very short, revealing his smooth forehead. The collar of his white lab coat bore the Tsinghua and Peking University badges, which gleamed coldly under the light. The folder in his hand had worn edges, clearly indicating it had been frequently handled.

The moment their eyes met, the air seemed to freeze.

Zheng Yiming paused, a flicker of surprise crossing his eyes before he regained his usual composure, though his fingers tightened slightly around the folder. The boy beside him pushed up his glasses and broke the silence with a smile: "Looks like we didn't come to the wrong place. The physics lab at Peking University is indeed quite impressive."

"Who are you?" Jiang Yi stood up, his tone politely distant.

“Hey, you're from the Physics Department at Tsinghua or Peking University, I'm here to borrow your XRD diffractometer. Our instrument is broken.” The boy pointed to Zheng Yiming. “My name is Zhou Ziang, and this is Zheng Yiming.”

Zheng Yiming nodded to us, his gaze lingering on the coffee stains on my white coat for half a second before quickly shifting to Jiang Yi, a subtle scrutiny in his eyes.

“The equipment is currently in use,” Jiang Yi said, stepping aside to block my lab table. “If you’re not in a hurry, you can come early tomorrow morning, and I’ll have the administrator keep it.”

“There’s no rush,” Zhou Ziang said, peering into the lab and looking at the crystal lattice image on the screen. “You’re doing semiconductor material analysis? What a coincidence, we’ve been working on a similar project recently. Maybe we can exchange ideas.”

I lowered my head, pretending to organize data, my pen scribbling messy lines on the notebook. Zheng Yiming's scent was nearby, carrying the unique soapy fragrance of a freshly washed white lab coat, completely different from the turpentine smell in the art studio in high school, yet it still made my heart skip a beat.

“We haven’t finished organizing the data yet,” Jiang Yi said in a gentle but firm voice. “Let’s talk about it after the project is completed.”

Zhou Ziang was clearly not expected to be rejected. He paused for a moment, then smiled awkwardly and said, "Okay, then we'll come again tomorrow."

Zheng Yiming didn't say a word from beginning to end, but he glanced at me again as he turned to leave. His gaze was complex, as if a thousand words were stuck in his throat, but in the end, it only turned into a very faint nod, as if to say, "Long time no see."

The moment the lab door closed, I realized my hand holding the pen was trembling. Jiang Yi handed me a tissue: "Why are your hands so cold?"

"It's nothing," I said, taking the tissue and wiping the sweat from my palms. "It's probably because the air conditioning was set too low."

He didn't press further, but simply sat back down in his chair and pointed to the data on the screen: "The peak values ​​here are a bit abnormal. Is it a problem with the sample purity?"

After returning to work, those inexplicable feelings of excitement gradually subsided. But Zheng Yiming's image kept lingering in my mind—the school badge pinned to his white coat, his slightly clenched knuckles, his last hesitant look in his eyes, all like pebbles thrown into a lake, rippling outwards.

The next morning, the administrator said that the people from Tsinghua and Peking University had already borrowed the equipment. When I went to the archives to look up literature, I ran into Zheng Yiming again in the corridor. He was standing in front of the bookshelf looking for information, and the sunlight shone through the high window onto the ends of his hair, gilding them with a layer of gold. The lines of his profile were more rugged than in high school.

The aisle between the bookshelves was narrow. I was carrying books and trying to walk around him when he happened to turn around, and the books in his arms tumbled to the floor. "Solid State Physics," "Semiconductor Device Physics," "Introduction to Quantum Mechanics"... one after another, lying on the floor, just like his slightly disheveled expression.

"Sorry." We spoke at the same time, our voices colliding, and then stopped simultaneously.

I crouched down to pick up the book, and my fingertips just touched the cover of "Introduction to Quantum Mechanics" when they collided with his. His fingertips were cold, with the rough texture of the paper, like the icy-cold fountain pen that was handed to me back in high school.

"I'll do it." He pulled the book closer to himself, his movements so quick it was as if he were dodging something.

“It’s nothing.” I insisted on picking up the book and handing it to him. As I did so, I noticed a line of small print on the title page: “September 15, 2023, I overlooked the boundary conditions when solving the Schrödinger equation.”

The date was when he first entered school. His handwriting was neater than in high school, but it still carried a touch of sloppy sharpness.

"Thank you." He took the book, hugged it to his chest, and his gaze fell on the "Semiconductor Materials Characterization Techniques" in my hands. "You also do materials analysis?"

"Yes, it's my supervisor's research topic."

“Our research topics overlap somewhat,” he paused, seemingly considering his words, “If you encounter any problems, you can… contact Zhou Zi’ang; he is very familiar with XRD diffractometers.”

The words "find me" were deliberately avoided, as if drawing an invisible line.

"Okay." I nodded, holding the book, and walked past him sideways. My shoulder accidentally bumped into his arm, and it felt like touching a piece of ice.

I walked quite a distance from the reference room before daring to look back. Zheng Yiming was still standing in front of the bookshelf, clutching the book "Introduction to Quantum Mechanics" in his hand, his gaze fixed on the direction I had left, like a silent statue.

Jiang Yi was waiting for me at the lab entrance, holding a newly printed document in his hand: "The administrator said that people from Tsinghua and Peking University sent us the diffraction data for our reference."

I took the document, and on the first page, the signature read "Zheng Yiming and Zhou Ziang," the handwriting strong and powerful, exactly like his signature on his competition notebooks in high school.

“It seems their research topic is indeed similar to ours.” Jiang Yi pointed to the experimental design in the literature. “The control group is cleverly set up and is worth learning from.”

I stared at the name "Zheng Yiming" and suddenly remembered the last mock exam in high school, where there was an obvious calculation error on his math paper. Back then, he always said that "physics is more interesting than math," but now he can make meticulous experimental designs without any flaws, like a piece of polished jade that has lost its rough edges.

On the day we submitted the final report of the project, our supervisor specifically praised us at the regular meeting: "The data integrity and innovation are outstanding, especially the part about the cooperation with Tsinghua and Peking Universities, which deserves recognition."

After the meeting, Jiang Yi said that Tsinghua and Peking Universities had sent a message wanting to co-publish a paper. "Zhou Zi'ang said we should meet at a coffee shop near Weiming Lake this weekend to discuss the details."

My hand holding the mouse paused for a moment: "Will Zheng Yiming be going too?"

"Probably, he's the first author." Jiang Yi looked at me. "You don't want to see him?"

“It’s not that I don’t want to,” I sighed, “it’s that I don’t know what to say.”

"Just treat it as meeting a regular collaborator." Jiang Yi smiled. "Your current research is so good, you should be proud."

The café was filled with the rich aroma of lattes, and ginkgo leaves outside the floor-to-ceiling windows twirled and fell in the wind. When Jiang Yi and I arrived, Zheng Yiming and Zhou Ziang were already seated by the window. Zheng Yiming was wearing a gray hoodie, the hood pulled up over his head, covering half his face and revealing only his sharply defined jawline.

"Sorry I'm late." Jiang Yi pulled out a chair, sat down, and pushed the printed first draft of the paper over.

“It’s alright, we just arrived too.” Zhou Zi’ang smiled as he took the first draft and pushed it to Zheng Yiming. “Take a look, the experimental data supplemented by Yanyuan is very complete.”

Zheng Yiming lifted his hat, revealing his clear eyes. His gaze lingered on my face for half a second before landing on the paper. His fingertips traced the data analysis section I had written, his movements very gentle, as if afraid of damaging something.

“The error analysis here,” he began, his voice lower than in high school, “uses a weighted average method? It’s more accurate than the least squares method we used.”

“It was Zhixia who came up with it,” Jiang Yi looked at me with a smile in his eyes, “She’s very sensitive to data.”

Zheng Yiming paused on the three characters "Chen Zhixia" with his pen. When he looked up at me, there was a complex emotion in his eyes, as if something was breaking through the soil, but was quickly suppressed.

The discussion of the paper went smoothly. We each had our own focus on experimental methods, which led to many new ideas. Zhou Ziang was very talkative and always made serious academic discussions more relaxed; Jiang Yi had clear logic and always grasped the key issues; Zheng Yiming was not talkative, but he always offered precise suggestions on details, like a precise scanner.

When it came time to discuss the authors' ranking, Zhou Ziang smiled and said, "In terms of contribution, Zheng Yiming is first, Shen Zhixia is second, and Jiang Yi and I are tied for third. What do you think?"

Just as Jiang Yi was about to nod, Zheng Yiming suddenly spoke up: "Let Shen Zhixia be ranked first, her data analysis is the core."

I paused for a moment: "But your experimental design..."

“Design can be imitated,” he interrupted me, his gaze serious, “but sensitivity to data is a talent, and it should be ranked higher.”

The café's music flowed softly, and ginkgo leaves fell onto the windowsill like silent letters. Looking at the earnestness in his eyes, I suddenly remembered how he always said in high school, "Your problem-solving approach is clearer than mine." It turns out that some things have never changed.

As we left the coffee shop, Zhou Ziang pulled Jiang Yi aside to discuss the follow-up submissions and walked ahead. Zheng Yiming and I followed behind, keeping a two-step distance, and neither of us spoke.

As we passed Weiming Lake, he suddenly stopped: "Your white coat..."

"Um?"

"Has the coffee stain been washed off?"

I was taken aback for a moment, then laughed: "It's already been washed clean, I used a strong stain remover."

He smiled too, the curve of his lips softer than in high school, like a pebble smoothed by lake water. "That's good."

The wind swirled up ginkgo leaves from the ground, landing them on his hoodie like golden butterflies. Looking at that leaf, I suddenly remembered the dried ginkgo leaves I'd thrown in the trash during my senior year of high school. A gentle, bittersweet feeling washed over me, a touch of sadness mixed with warmth.

“Zheng Yiming,” I began, my voice very soft, “about the past…”

“That’s all in the past.” He interrupted me, his gaze fixed on the lake. “We’re collaborators now, which is great.”

Yes, it's great.

No longer lovers, no longer enemies, but collaborators who can stand shoulder to shoulder academically. Like two trains that once veered off course, they eventually find themselves running smoothly on their own tracks, occasionally crossing paths, only to politely honk their horns as a signal before continuing on their way.

Jiang Yi called my name from ahead, and I answered and ran towards him. When I looked back, Zheng Yiming was still standing by the lake, ginkgo leaves sliding off his shoulder. His gaze fell on me, as if with a hint of relief and a hint of blessing, which finally turned into a very faint smile. He turned and left with Zhou Ziang, who had caught up with him.

"What are you thinking about?" Jiang Yi handed me a cup of hot milk tea. "Your face is all red."

"It's nothing," I said, taking the milk tea from my fingertips, the warmth of which made me feel at ease. "I was just thinking about where to celebrate after my paper is published."

"How about we go eat at that tomato hot pot place you mentioned?" Jiang Yi said with a smile. "I remember you really liked it in high school."

I paused for a moment, then nodded: "Okay."

He remembered my casually mentioned preferences as naturally and appropriately as he remembered constants in a physics formula.

The breeze by the lake was cool, yet it warmed my heart. As I watched Zheng Yiming's receding figure, I suddenly understood that the meaning of reunion is never about returning to the past, but about confirming that we have all grown into better versions of ourselves in our own lives.

Zheng Yiming will continue to pursue his physics dream in the laboratories of Tsinghua and Peking Universities. His rigor and sharpness will make him an outstanding researcher. As for me, I will continue to explore the mysteries of semiconductors in the classrooms of Peking University. My sensitivity and meticulousness will also shine in my own field.

We may meet again at academic conferences, collaborate on joint projects, or, like today, discuss data across a table and say "goodbye" from a distance. But all those past moments of excitement, hurt, and entanglement have become nourishment for growth, allowing us to walk more steadily and further on our respective paths.

The setting sun bathed the lake in gold as Jiang Yi and I walked side by side toward the dormitory, our shadows stretching long, occasionally overlapping before quickly separating again, yet always heading in the same direction. The ginkgo leaves rustled beneath our feet, like a song of reunion and growth.

The best reunion is not about rekindling old dreams, but about looking at each other honestly and saying, "You're doing well, and so am I."

The best future isn't necessarily about traveling together, but about knowing that you're both on your own course, growing vigorously, and living passionately and openly.

Just like Weiming Lake at this moment, the water is clear and the sun is shining brightly, and we are all heading towards our own brand new dawn.