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

Einstein approached the director of patents and said, "Director, this is a new patent on drive shaft differential submitted by Mr. Li Yu, an academician from the Royal Society of England. After my preliminary inspection, there is no problem. After your review, you can seal it and pass it." gone."

The director was puzzled: "Li Yu? This name is a bit familiar."

"Director, if there is nothing else, I will leave today, and I will make up my shift in two days!" Einstein dragged Li Yu home after speaking.

The director sat at the desk and was stunned: "Li Yu, which Li Yu is it?"

At Einstein's home, Li Yu saw his wife, Mileva.

This is a bit of a sad woman, I can only blame Einstein for being romantic and playful...

Einstein said loudly when he entered the door: "Quick! Mileva, prepare a good Ceylon black tea. I want to do some research with Academician Li Yu."

"My God, it's really him!"

Mileva also has a background in mathematics and science, so of course she knew Li Yu's name, and immediately began to prepare for the treats.

"Let me help you." Lu Bicheng stepped forward and said.

In terms of these housework, Orientals are much more meticulous and refined than Western women.

"What an ingenuity!" Mileva couldn't help admiring.

But Einstein didn't bother to drink tea at all. When he came to his desk, he took out his latest manuscript: "I received your manuscript a few months ago, and immediately started to think about time. But I have no mathematical tools. , My research has advanced to this point, as if I have encountered an invisible wall, and I can't get through it no matter what."

Of course, Li Yu understood that this was the famous Minkowski's theory of geometric space. Historically, it was through his help that Einstein completed the proof mathematically.

However, Li Yu was also very familiar with this thing, so he took the pen and said, "It can be done like this."

He skillfully wrote on the paper.

In less than half an hour, I wrote a few pages of mathematical calculations.

Einstein was very hooked: "You are like breathing when you face complex mathematical problems. I am really amazed."

Li Yu said: "But the premise is the same as we mentioned earlier. We must follow an important basic assumption, that is, the speed of light is constant. Based on it, we can use the Lorentz transformation to complete the conversion of space and time in four-dimensional space-time." .”

"It's so gratifying, I didn't expect you to have such a point of view!" Einstein felt that he had finally met a confidant.

For quite a long time when the theory of relativity was proposed, few people could understand it at all.In the first few years, there were no more than ten people in the world who understood the theory of relativity.In a sense, Einstein was relatively lonely on the road of scientific research, especially in terms of relativity.

Of course, this also highlights his greatness.

Li Yu said: "After the transformation of time and space, it really looks shocking. For a pair of twins, if the elder brother takes a spaceship close to the speed of light, he will be much younger than the younger brother when he returns."

That is the famous twin paradox in the theory of relativity.

"Before, I couldn't logically make this problem self-consistent. Now that there is a transformation relationship, it seems much more reasonable." Einstein said.

However, because the current speed that humans can achieve is too low, it is impossible to do related experiments.

Experimental physicists had always been at the top, and then theoretical physicists turned around. Now it is a junction time point, and even the status of experimental physicists seems to be higher.

If you can't make an experiment, it really lacks a little convincing.

For the next day, Li Yu and Einstein studied more transformation relations, such as the famous scale effect.

It also involves a very tangled one: dynamic mass.

In the future market, most people can already understand that when running at high speed, the time and length will change due to different reference frames.

However, there is still a lot of controversy about the dynamic quality.

But at present, most scientists can accept it; but there are still some who cannot accept it, such as the famous Landau.

But they also have to admit that many places cannot be explained without the viewpoint of dynamic mass.

For example, why an object with mass will never reach the speed of light is due to the Lorentz transformation of kinetic mass.

Once an object has mass, no matter how small its own mass is, even if it is just a tiny electron, if it reaches the speed of light, its dynamic mass will become infinite.

(In fact, because the denominator in the transformation formula becomes 0, it has no meaning in mathematics.)
Isn't this the same as creating a singularity.

Therefore, any object with static mass cannot reach the speed of light, let alone the so-called super-light speed in some science fiction themes.

It can be explained to some extent by using the curvature of space, but it is impossible to simply accelerate an object to the speed of light, and the energy required is much more than all the energy in the entire universe combined.

The transformation of the theory of relativity involves many views of time and space. In later generations, under the subtle influence of long-term study, most of them understand it. But at the beginning of the [-]th century, even a twin paradox was a super thing.

After a day of research, Einstein was very excited: "Sir, you are really talented!"

Li Yu said with a smile: "This is only a part, there will be many theories about time and space in the future."

"Yes, I still have a lot of ideas, but with these derivations from my husband, I feel that the follow-up work will be much easier." Einstein said.

To sum up, what Li Yu is proposing now is the core assumption in the theory of relativity that the speed of light is constant, as well as the scaling effect, time slowing down, etc., and uses his own mathematical ability to deduce it.

As for the other core mass-energy equation of special relativity, let Lao Ai publish it by himself.

In other words, the derivation of the substantial energy equation is not complicated, and it is not difficult to understand. It is to use the kinetic energy formula E=mv of classical mechanics, and then substitute the relativistic mass, and then use the differential to derive it. A high school science student can understand it.

Li Yu has already handled the more complicated four-dimensional space-time-related mathematical content in special relativity for Einstein.

However, there are still many physical explanations that Einstein needs to continue to improve. This is not a small project, enough for Einstein to "focus on fishing" in the patent office in the next few months.

Li Yu said, "I finally understand why your hair is like this."

Einstein wondered, "Why?"

Li Yu smiled and said, "You have to go to work every day, and you have to study so many physics problems, it would be strange."

Einstein also said with a smile: "I don't want to let those professors at the Federal Institute of Technology in Zurich laugh at me again, I want to let them know what real physics is!"

——It won't take long.

Li Yu looked at the piles of papers on the table and said, "Your Excellency will need to organize the orderly arrangement and the specific thesis yourself."

Einstein said: "Naturally, I will name you together in the article, after all, you have made so many contributions."

Einstein credited half of the credit for the invention of special relativity to Li Yu.

Li Yu smiled and said, "Actually, I don't do much."

"Quite a lot already!" said Einstein, "otherwise I would not have sorted out so many problems so quickly."

"Ok."

Anyway, it doesn't prevent him from winning the Nobel Prize for the photoelectric effect and the dazzling mass-energy equation, not to mention the truly awesome general theory of relativity in the future.

It's just that when later generations learn the theory of relativity, when they talk about the profoundly significant constant speed of light and the transformation of the theory of relativity, they have to talk more about Li Yu.

Einstein was busy during this time, so Li Yu took his leave temporarily, and said before leaving, "Don't forget my patent application, I will leave this matter to you."

Einstein promised: "Don't worry!"

"If there is a patent application in the future, I will continue to trouble Mr. Li." Li Yu said.

Einstein laughed: "On behalf of the director, thank you for taking care of the business."

Einstein spent seven years at the Berne Patent Office starting in 1902.

Nowadays, patents in Europe and the United States only need to be applied for in one country, regardless of the United States, Switzerland or Germany, and there will be no major obstacles to their use.

It's interesting to think that there are still many patents that Einstein needs to seal and review.