The morning's lecture was over, but people were still talking about it with relish.
Li Qiwei, meanwhile, had finished his business and left without a backward glance, strolling leisurely to the place he had arranged to meet Wilson.
The legendary Cavendish Laboratory!
Physics was an experimental science.
A physical theory could only be accepted as valid after it had been verified by experiment.
That made physical experiments extremely important.
In the eighty-five years from 1904 to 1989, the Cavendish Laboratory produced a total of twenty-nine Nobel Prize in Physics laureates.
Terrifying!
The laboratory had been founded in 1871 by Maxwell, a god-tier genius.
He had also been its first director.
The laboratory's current director was its third, a man named Joseph Thomson.
One sentence was all it took to sum up this big shot: he discovered the electron in 1897.
Wilson was Thomson's student, and he had another even more impressive student: Rutherford.
Just as Li Qiwei was marveling at the greatness of the Cavendish Laboratory, Wilson spotted him.
"Bruce, come over here. I'll introduce you to an important figure today."
Wilson led Li Qiwei to a conference room, where a middle-aged man was already seated. It was the very man who had handed him the blackboard.
Wilson wore a respectful expression as he pulled Li Qiwei into a seat.
"Professor Planck, I'm terribly sorry. My supervisor had an urgent matter come up, so he specifically asked me to host you."
The middle-aged man, Planck, had a sharp gaze. He smiled and said, "It's all right. Thomson and I are old friends."
Hearing their exchange, Li Qiwei was deeply shaken.
Sure enough, once you got to Cambridge, every random person you ran into was a big shot.
Information about the middle-aged man surfaced in his mind:
"Max Planck, born in Germany in 1858."
"In 1879, he graduated from Berlin University with a doctorate in physics."
"In 1894, he was elected a member of the Prussian Academy of Sciences."
"In 1918, he received the Nobel Prize in Physics."
That famous before-and-after photo comparison of people studying physics that had once been popular back home featured this very man.
And if history had not deviated, Planck would formally propose the concept of energy quantization this December.
Einstein had drawn on this concept to propose the Light Quantum, proving the Photoelectric Effect and earning the Nobel Prize for it.
Physics was divided in two by Planck's proposal of the quantum concept: what came before was called Classical Physics, and what came after, modern physics.
By Li Qiwei's ranking system, this man was a future T2-level big shot!
Then, with Wilson introducing them, Li Qiwei formally met Planck as a junior student.
"Professor, how did you know Bruce was here?" Wilson asked.
"Oh, I was at yesterday's conference in London," Planck said.
"Oh, how incredible. And as luck would have it, you accepted my supervisor's invitation to come lecture at Cambridge," Wilson said.
At last, Li Qiwei understood what was going on.
His bold words the day before had caught the attention of this big shot, sparking his interest.
A month earlier, Thomson, director of the Cavendish Laboratory, had invited Planck to lecture at Cambridge.
Then Planck had come across Dr. Wilson's test problem.
He had quietly watched Li Qiwei, to see whether this young man had real ability.
The result had clearly satisfied him; otherwise, he would not have met with Li Qiwei.
Seeing that the two had become acquainted, Wilson said, "Professor Planck, I have something else to take care of. Please give Bruce some guidance."
Then he added, "He's the most promising young physicist I've ever met."
Planck smiled faintly. Once Wilson had left, he turned to Li Qiwei and said, "Bruce, would you care to take a walk with me?"
"It would be my honor, Professor," Li Qiwei replied.
April's weather was bright and sunny.
Li Qiwei and Planck strolled casually around Cambridge University, talking as they went.
Planck was astonished by Li Qiwei's grasp of physics.
It seemed there wasn't a field he knew nothing about.
Planck couldn't help wondering: had Cambridge University's teaching really reached such an incredible level?
As their conversation grew more and more lively, they soon came to the most famous problem of the day: the Cloud Problem.
Li Qiwei spoke freely, his wild flights of thought astonishing Planck once again.
Before long, they reached a stone arch bridge over the Jian River. It was also the Cambridge Bridge made famous in Farewell to Cambridge.
The Jian River rushed beneath them, just like the turmoil in Planck's heart.
"Bruce, do you really believe that energy can come in separate portions, that it can be quantized?"
That was right: Li Qiwei had formally proposed the concept of Quantization several months ahead of schedule.
The idea sent shock waves through Planck. It ran completely counter to Classical Physics.
Newton's conception of absolute space and time was continuous. How could it possibly come in separate portions?
In history, even after proposing the concept of Quantization, Planck had indeed agonized over it again and again.
Because if he accepted it, then everything he had learned in the first half of his life would be wrong.
Nevertheless, out of respect for scientific fact, he had published the idea.
Li Qiwei believed that Planck was already considering Quantization. He just needed something to reassure him.
"Professor, only energy quantization can perfectly solve the second cloud, the problem of Blackbody Radiation."
"Recently, I've completed most of the mathematical calculations and can reasonably explain the radiation intensity near the short-wavelength end."
"But there are a few difficult points I haven't been able to resolve."
"I know you studied mathematics at the University of Munich. Could you take a look and see how these mathematical problems might be solved?"
"I think this will be a remarkable achievement."
Planck was so astonished that he was speechless.
Yes, he himself had already been considering Quantization, but he had never expected Li Qiwei to have started calculating it already.
And the key point was, this young man was only twenty!
In his eyes, Bruce was a genius born for physics!
By now, Planck completely believed Bruce's bold claim: physics had only just begun!
He held back his excitement and said, "Excellent, Bruce. Don't worry. I'll help you complete the mathematical calculations, and I won't steal your work."
Li Qiwei was deeply moved. This was the mettle of the older generation of physicists.
They pursued only the truth, caring nothing for fame!
He smiled. "Thank you, Professor. But I have a better idea. I'd like you to be the Corresponding Author of my paper."
"Corresponding Author?" Planck was taken aback. He had never heard of the concept.
Li Qiwei explained, "We have an old saying in the East: when you meet someone excellent, you can take him as your teacher."
"Although I'm not your student, talking with you has taught me a great deal, and you're helping me solve a crucial mathematical proof."
"I think you could certainly be my teacher."
"Being the Corresponding Author means that I completed this paper under your guidance."
"We can make that clear in the paper."
After hearing Li Qiwei's explanation, Planck realized that he had underestimated the young man.
He was already a member of the Prussian Academy of Sciences, a man who had made his mark. He didn't care about gaining even greater fame.
Li Qiwei, by contrast, was only an undergraduate. He could have claimed all the credit for himself.
Yet he was so humble and composed. It was truly admirable!
Planck felt a surge of affection for this talented young man. He looked at Li Qiwei as if he were a priceless treasure.
"Bruce, I accept your suggestion. Send me the draft of your paper as soon as you can, and I'll check the mathematical sections."
"Thank you very much, Professor," Li Qiwei replied earnestly.
Then the two, now teacher and student, looked together into the distance along the Jian River. Their hearty laughter rang out over the water.
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