A Man of Science and Engineering in Troubled Times Wandering in the Late Qing Dynasty

This trip to Japan made Li Yu almost become the top leader in Japanese academic circles, and he achieved remarkable results. A portrait carefully painted by Zheng Jin was hung on the Tokyo Imperial University, ranking him behind a group of scientific tycoons.

But what satisfies Li Yu the most is that many top students from Tokyo Imperial University have really begun to follow the "high-end academic route" Li Yu has set for them, especially in advanced mathematics and mathematics-focused physics.To put it simply, they are all theoretical directions.

These are also the directions that Li Yu is good at.

For a developing country, engineering application content is actually more meaningful. At least it must first solve whether it is available or not before it can consider whether it is good or not.

After Li Yu prepared to return to China to study, he deliberately cultivated more engineering talents.Of course, pure science cannot be given up. After all, it is cheaper to learn pure science, and children from ordinary families can also learn it.

Li Yu got on the boat back home.

From the map, it is most convenient for ships departing from Tokyo or Yokohama to go to Shanghai first, and then some routes choose to continue north to Qingdao and Tianjin, while others go south to Xiamen and Guangzhou.

Li Yu already has two residences in Shanghai, one is a small foreign-style building on Dongping Road, Shanghai, and the other is Yuyuan Garden.

Yuyuan Garden is mainly used for occasional relaxation. In addition, it is large and can be used as a gathering place and storage place.

As soon as he arrived at the Dongping Road villa, Li Yu saw that his mailbox had received many scientific magazines and telegraph letters from Europe and the United States, including many from Einstein, Lord Kelvin, Planck and other big names.

Li Yu took a closer look and found that Einstein was still not famous today, but had only changed from a temporary third-level patent officer to a second-level official patent officer.The income has increased by one thousand francs to 4500 francs (approximately US$900), which is indeed helpful to improve the quality of life.

However, his clothes and hairstyle are still the same, and he can be recognized at a glance in a crowd.

Planck valued him very much and had already given two public lectures dedicated to explaining Einstein's theory of relativity.Although it attracted the attention of some physicists, it still did not let Einstein out of the circle.

You can't be a physics professor without fame.

Physics professors in some universities earn very high salaries. The most typical ones are universities in the United Kingdom and the United States. The salary of a professor is at least eight or nine hundred pounds, which is about more than 4000 U.S. dollars.If you include other scientific research funds, school subsidies, and Academy of Science subsidies, you can easily get seven to eight thousand US dollars a year.At the beginning of the [-]th century, income levels were definitely at the top level.

As for Germany, although the academic level is considered to be the first level, to be honest, the income level of German professors is much lower than that of the United Kingdom and the United States.However, prices in Germany were relatively stable at this time, and the professors were at least upper class.It was not until the beginning of World War I that the German mark devalued greatly, which was a disaster.

Einstein really wanted to be a university professor who only studied physics, but there was no way.

On the other hand, Li Yu has already received invitations to be professors from many universities, but he doesn't have time to go yet...

Li Yu opened a letter from the University of Zurich in Switzerland, in which the University of Zurich stated that it could create a visiting professor position in mathematical physics for Li Yu.

Li Yu didn't know how to reply for a while.

He opened another letter from Einstein:
"Mr. Li Yu of the East,

"You know, I enjoy discussing physics problems with you. Your ideas are rare and ahead of the times.

"Recently, I have been studying the expansion of the theory of relativity, such as how to apply it to the reference frame of accelerated motion. However, I have encountered huge mathematical obstacles, as if a high wall stands in front of me. Mileva It helped me solve some math problems, but as I continued to think and study, insurmountable math came up.

“Oh my god, it’s so disappointing!

"I think I should really pay attention to and study mathematics like you. But I have never been interested in mathematics. It is difficult to continue reading after half of the mathematics books I borrowed from the library.

"Looks like I should slow down this research."

Li Yu couldn't help but smile when he read this. Who said otherwise? Mathematics determines the upper limit of difficulty in physics.

The physics itself is really not that difficult, the key is the math behind it which is maddening.

I guess some people who have participated in competitions in high school will be very impressed.

As for competitions, math competitions are definitely more difficult than physics competitions. (But it doesn’t mean which one tests your intelligence more.)
Even if it is just a high school mathematics competition, the scope of the questions does not involve any college mathematics knowledge, and the questions can still be extremely difficult.

It can be said that there is no upper limit on the difficulty of the questions in high school mathematics competitions.

Some International Mathematics Olympiad (IMO) questions make even university mathematics professors feel blinded.

But physics competitions have an upper limit, that is, the upper limit of human physics cognition.The problem must be solved with the help of existing physical theorems, and there is not much room for free play.

Physics competitions are no match for senior physics majors at top universities.Any physics difficult problem can be found in an advanced tutorial or paper to find the basis for the proposition and the solution.

In short, the most difficult math questions can form an excellent paper; while the most difficult physics questions can never surpass existing papers.

In addition, there are no rules in mathematics competitions. Questions can be asked as wildly and as wildly as you like, and there are many ways to solve problems.To prepare for math competitions, you need to answer a lot of questions and be relatively talented.

But physics is very organized: after finishing college calculus and four elementary mechanics, all that is left is some problem-solving skills.Because from a high perspective, the questions in the physics competition can be very simple and feel a bit like a dimensionality reduction attack.

Li Yu prepared for a physics competition in high school and had to learn a lot of mathematics.Later, when I went to college, I had even more feelings: being good at mathematics may not necessarily mean you are good at physics, but being good at physics will never be bad at mathematics.

I just never thought that Einstein, the great master of physics, would also have this kind of mathematical troubles.

The rest of Einstein’s letter was a little helpless:
"I'm going to do something else first, like inventing a machine that can amplify electric charges. I've been working on it for months, and now I can induce ten times the current with a few metal rods, and then I can By transferring them to disks and repeating the process a few times, they were able to amplify the weak current. "I thought it was a genius idea, but the problem was how to make them work.I have attached the design drawings at the back of the letter. I know that when you were in the United States, you designed and manufactured excellent instruments such as radio equipment, so I believe you will have corresponding ideas.

"..."

Li Yu pulled out the drawing at the back and was even more confused about whether to laugh or cry.This design must be said to be ingenious, and it is indeed ingenious, but it is still far from being a truly outstanding experimental physicist.

If experimental masters like Marie Curie or Rutherford saw this, they would definitely throw it into the wastebasket. After all, the experimental instruments designed by these two people are more accurate than Einstein's, not by percentage, but by several degrees. orders of magnitude.

Li Yuxian replied to the University of Zurich and recommended Einstein in the letter:
"I am honored to receive the invitation from your school. However, I am too far away from Europe to go there. But beside you, there is actually an outstanding physicist. His name is Albert Einstein. A Ph.D. from ETH Zurich. Mr. Einstein has published several excellent papers in the Annals of Physics, discussing the most advanced physical ideas such as the photoelectric effect and the theory of relativity. He will never let you down."

As for Planck’s letter, you already know what it’s about without saying it. In addition to asking about the recent academic situation at the beginning, he was chatting with Li Yu about when to publish the follow-up to Star Wars...

In his letter to Einstein, Li Yu first encouraged him to engage in experimental innovation, and then elaborated on the correct arguments about the theory of relativity. For example, the theory of relativity will definitely follow a basic principle in physics-minimum action. quantity principle.

In his letter to Planck, Li Yu also talked about relevant content.

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Germany, University of Berlin.

Planck was in his office looking at recent student papers and physics journals.

There was a knock on the door, and his master, Laue, walked in: "Professor, a letter from Li Yu."

"Oh my God!" Planck put down the red wine glass. "Is the Pacific Ocean blocked again? Why did it take so long to send it back?"

Planck first read Li Yu's reply. First of all, he was quite satisfied with Li Yu's reply. The Star Wars biography will be printed next year.

Then there are some thoughts on the theory of relativity.

After reading it, Planck took out a postcard from the table that Einstein had sent a few days ago and said to Laue: "A young man named Einstein in Switzerland once invited me to Switzerland, but I have always I don’t have time, so I’ll let you go on my behalf this time.”

As a German aristocrat named von, Laue liked this job very much because it was already the ski season in Switzerland and the Alps were full of white snow. He loved skiing.

Laue happily took the train to Bern the next day. He went straight to the University of Bern, but after asking around, no one knew about Einstein.

It took him a lot of effort to find out that Einstein did not work at the university, but in the Patent Office in the Post and Telegraph Building.

Laue could only go to the patent office again and saw Einstein through the window who was immersed in patent review.

"Is it really the Einstein who published the theory of relativity and explained the photoelectric effect?" Laue said to himself, he couldn't believe it at all.

After a few minutes, Einstein raised his head and reached for a stack of papers in front of his desk.

Laue saw his face, and it turned out to be Einstein.

The two had met before at the Prussian Academy of Sciences. As they were similar in age and both studied physics, it was easy to establish a friendship, so Laue was deeply impressed by him.But this situation was so different from his own psychological expectations that he could not put the founder of the theory of relativity and the patentee in front of him together.

It was not until a staff member from the Patent Office came over and asked about the purpose of his visit that Laue explained to him that he wanted to find Einstein.

"It's Albert Einstein, not anyone else," Lauerdo explained.

"That's right, it's him. There's no other Einstein in the whole of Bern." The staff member replied, and then called Einstein out.

"What a surprise," Einstein said. "I didn't expect you to come to Switzerland."

Laue took out Planck's postcard: "Mr. Planck doesn't have time, so I'm here to accept your invitation."

"I'm equally happy that you can come!" Einstein said, "Let's go and show you the scenery of Bern. It is much more comfortable here than Berlin."

"It's really refreshing, at least not as tense as Berlin." Laue said.

Einstein took him to a bridge and handed Laue a cigar.

Laue lit it up and took a sip, frowning: It’s too bad, the taste is super unpleasant!
After all, Laue was a wealthy aristocrat, and cigars of this quality obviously did not catch his eye, so he accidentally dropped the cigar into the river.

"It's such a pity." Laue said with relief.

The subsequent communication between the two was smooth. Last time, Leonard's sudden speech disrupted the rhythm. This time, the two were able to talk about physics seriously.

One afternoon later, Laue was completely convinced: "It's hard to imagine that you have such an extraordinary imagination. You are exactly the same as Li Yu from the East. It's unbelievable."

Einstein said helplessly: "But I still can't gain any fame. After a few papers were published, the entire physics community was simply silent."

"At least there are still people who like it, such as Mr. Planck, Mr. Li Yu, and me," Laue comforted. "But I heard from many academic groups that they think your theory is difficult to verify experimentally. This is unacceptable to most physicists."