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

Duan Zhigui's tricks did not work this time. The censors were sharp-eyed and quickly impeached Yikuang and his son.

Standing behind the censor was Qu Hongji from the Qingliu sect.

It's just that money can make things worse, so Yikuang suppressed the matter and instead framed the censor for spreading rumors.

But they obviously did not understand the power of the media. Newspapers such as Shenbao repeatedly reported on the matter; Cen Chunxuan also wanted to use this to bring down Yuan Shikai and Yi Kuang, so that the Qing Dynasty could breathe a few more breaths.

Cen Chunxuan directly brought the matter to Cixi, but Cixi just asked Duan Zhigui to be dismissed from his post; Zai Zhen was also implicated and resigned from all positions, and thereafter he had no voice in official circles.

However, Cen Chunxuan and Qu Hongji irritated Yi Kuang. They originally just wanted to be a quiet money-making expert, but they had to push themselves into a dead end, so they teamed up with Yuan Shikai to expel them directly from Daqing Company.

Yuan Shikai knew that Cen Chunxuan had a good relationship with Cixi, so he even took a photo of Cen Chunxuan and Kang Youwei.At this time, the photos are irrefutable evidence. How many people know that the photos can be faked?Cixi hated Kang Liang the most and immediately lost her mind...

As for Yang Cuixi, she became famous throughout the country because of this incident, and many people came to look for her.Although she was not a stunning figure, her popularity brought her popularity, and she instantly became a famous prostitute who shocked the whole country.

It is not easy for the first generation of female actors to achieve this level.

Li Yu naturally didn't want to care about their political battles. The Qing Dynasty was going to be gone anyway, so it was all pointless.

He was going to take Lu Bicheng on a trip to Europe and the United States.

When the students arrived and were about to leave, Qiu Jin suddenly came to the dock and asked to see the outside world.

Li Yu did not refuse, gave her a replacement ticket, and set off together.

If he didn't take her with him, she might not be able to control herself after hearing about Xu Xilin's death.

Xu Xilin died really tragically. After assassinating Enming, the governor of Anhui, he was caught by Enming's soldiers, beheaded, gutted, and even fried and eaten.

As the ship sailed toward the sea, Li Yu stared into the distance in trance.

Hu Gangfu, one of the students studying in the United States, came to the deck and said, "Master Emperor, can I ask you a question?"

Li Yu regained his composure and said, "Okay, what's the problem?"

Hu Gangfu said: "I have always been entangled in whether I should choose physics or mathematics after entering an American university."

"Like both of them?" Li Yu asked.

Hu Gangfu nodded: "I like them all."

Li Yu said: "If you like both, you will naturally choose physics. I can also give you two questions to verify."

Li Yu found paper and pen and asked a math question, which was roughly the level of the last big question in the college entrance examination. Then he asked a physics question, how to prove the existence of centripetal force when celestial bodies move.

This physics problem is indeed a little simple to say, but the physical ideas contained are quite good. It can be solved cleverly through the area ratio of Kepler's three laws and calculus.

——It also contains a little selfishness of Li Yu: I hope he chooses physics.

Sure enough, after spending most of the day, Hu Gangfu only solved the physics problem.

Li Yu said: "It turns out that you are more suitable for the physics major."

Hu Gangfu said: "But I still have a great obsession with mathematics."

Li Yu smiled and said: "Mathematics is not so amiable when you get to the deeper level. And studying physics will not delay you from learning mathematics. Even if you are not good at mathematics, you will not be able to do physics."

Anyway, Li Yu understood that even if he could get 145+ in mathematics in the college entrance examination, it would only be a preliminary indication that he was qualified to apply for mathematics major.

In his previous life, there was a famous saying in the Mathematics Department of Peking University: "Every year, there are always some students who have perfect scores in the Mathematics College Entrance Examination and apply for the Mathematics Department over their own abilities."

There is even this kind of conversation in the mathematics department dormitory:

——Freshman Xiao Ming: Hello everyone, I am the number one scholar in a certain province and have perfect scores in mathematics!

——Others: 6. You actually took the college entrance examination?
Hey, anyway, mathematics really requires too much talent. It seems that there are only masters and ordinary people, and there is no middle value.

But the mathematics major itself is pretty good. Once you understand it, you can go into computer science or financial systems.

"Master Imperial, I have another question," Hu Gangfu asked again. "When I was reading some interesting physics anecdotes you wrote, you mentioned that physics requires intuition. What kind of intuition is this?"

Li Yu thought for a while and said, "I just love thinking. For example, Archimedes discovered the law of buoyancy just by taking a bath. And it is well-founded and basic thinking. You cannot think randomly, otherwise it will become sophistry."

"Isn't Zeno's tortoise just sophistry? You said it stimulated the development of mathematics." Hu Gangfu said again.

"This is no longer a sophistry, it should be called a paradox," Li Yu said. "Let me tell you what sophistry is. For example, some people say that seeing a doctor is actually seeing a doctor, and a steamed bun is actually steamed bun with meat. , putting out fire is to eliminate the fire rather than save the fire, and then we come to the conclusion that the real world is contrary to the description, the white is actually black, and the black is actually white. Or the ancients said that the white horse is not a horse, all based on finite There is no scientific thinking at all to use the theory to infer the infinite world."

Hu Gangfu said: "I have indeed seen many such remarks."

During the Republic of China, Li Yu said with a smile: "This is a typical example of half-baked vinegar. Logic is not done in this way. It should be rigorous induction. Physical thinking is as profound as mathematical thinking. When you learn physics Then you’ll find mathematics everywhere.”

The ship stopped briefly in Japan, and Li Siguang got on the ship. Li Yu had made an agreement with him to send him to study in Europe and the United States.

After arriving in San Francisco, Tang Guoan took them to the barber shop to cut off their braids.

After staying for three days and filling out the documents at the U.S. Immigration Service, Li Yu received invitations from Michelson and University of Chicago President Judson, allowing Li Yu to take students to visit the University of Chicago.

Tang Guoan knew that Li Yu was very famous in Europe and the United States, so it was not surprising that he received an invitation from the University of Chicago as soon as he landed.

Tang Guoan studied law and did not know much about Michelson's status in physics, but he was very aware of Principal Judson's unparalleled glory in the American legal community as a constitutional expert.

The key point is that President Judson also gave Li Yu a lot of face and asked all Chinese students studying in the United States to visit the university.

It took two or three days to take the train from San Francisco to Chicago. Judson, the president of the University of Chicago, and Michelson, the chairman of the physics department, welcomed him.

As students lingered at the University of Chicago, Li Yu chatted with Michelson: "In this year's Stockholm voting results, it will be you, the professor, as expected."

Michelson smiled and said: "It's a pity that the dark clouds have not cleared yet. I seem to have caused trouble for physics."

Li Yu saw another physics professor from the University of Chicago who came with him, and asked, "Are you Professor Millikan?"

"Yes," Millikan replied.

"Nice to meet you!" Li Yu shook hands with him cordially, "I heard that you are re-conducting the experiment of measuring basic electric charge?"

"Even you know?" Millikan asked in surprise.Li Yu said: "I just received the latest batch of magazines a month ago and reported on them."

Millikan said: "Although Director Thomson of the Cavendish Laboratory and Mr. Wilson have done many experiments on basic charge, I still don't agree with their results because I have carefully studied their papers and the experimental process. There are errors that cannot be eliminated.”

Li Yu nodded: "I have read that the method they use is a cloud chamber, and what is measured is actually the average of the ion charges in the entire cloud and mist, which is not accurate."

"So even though the Cavendish Laboratory, the world's best, has come to a conclusion, I still can't accept it," Millikan said.

Li Yu asked: "Have you started the experiment?"

Millikan said, "Would you like to take a look?"

"It's an honor." Li Yu said.

Millikan led the way: "It is also rewarding for me to have the guidance of the world's top scientific giants."

Later generations rated the ten most beautiful physics experiments, and Millikan's oil drop experiment to measure basic electric charge was ranked among them.

But before him, scientists have been doing this experiment since the day the electron was first discovered, because the scientific community is very clear that as long as the accurate value of the basic charge is obtained, atomic physics will instantly advance to a higher level, and many formulas can also be greatly advanced.

This little thing is very crucial, and it can directly prove the existence of electrons, particles smaller than atoms, which is of great significance.

Arriving at Millikan's laboratory, Li Yu found that he was still repeating Wilson's experiment.

Millikan said: "Since last year, I have been dissatisfied with the large range of changes in Wilson's experimental values, so I repeated his experiment, but did not get more consistent results than his, which is somewhat disappointing."

Science is like this. There is a fog ahead. If you want to overthrow others, you must at least achieve the results of others.

The basic charge value previously obtained by Wilson was 1.03×10^-19 coulombs, and the accurate result of later generations was about 1.6, which is a bit different.

Li Yu said: "It will take a lot of time to use Wilson's method to produce stable results. It will probably take several years to design a new experimental plan."

Millikan seems to have been mentally prepared for this: "I have found assistants and asked the school to reduce teaching tasks to a minimum, and I will definitely complete this research. Because among all physical constants, there are two of outstanding importance, one One is the speed of light, which appears in many of the fundamental equations of theoretical physics; the other is the final, or fundamental, amount of electric charge."

This is Millikan's original words.

But Li Yu immediately realized that the measurement of the speed of light was completed by Michelson at the University of Chicago; and the measurement of the basic charge was completed by Millikan.

Not only does this suddenly raise the status of the University of Chicago, but it also allows Europe, which has always looked down on the American scientific community, to take a look.

It seemed as if the physical center of the world had instantly moved to Chicago.

Millikan showed Li Yu some of his experimental results. Li Yu knew the accurate data of the basic charge, so after taking a look at it, he said: "Wilson's method has reached its limit and must be improved. I think the most critical thing is Re-selection of experimental media.”

Millikan asked: "Experimental medium?"

Li Yu said: "If non-volatile materials are used instead of water droplets or ethanol used in previous experiments, the impact of evaporation will be significantly reduced, thereby greatly improving the accuracy of the experiment."

Millikan seemed to shudder and said excitedly: "What a genius idea!" Then he said thoughtfully: "But it requires a new set of instruments, which is more troublesome..."

The most critical part of Millikan's oil drop experiment is to replace water droplets with oil droplets, and at the same time find a way to measure the charge of extremely small oil droplets (even as small as close to the size of air molecules).

Even if Li Yu didn't tell him, Rutherford, the super god of experimental physics, would soon give him this reminder.

And Li Yu was not interested in this experiment.

Physics majors will do this experiment at the undergraduate level. It is really troublesome. It is estimated that [-]% to [-]% of people pass by changing the data.

But now we don’t even have experimental instruments. Just like the X-ray and radioactive research mentioned before, we must first build sophisticated experimental instruments before we can continue to conduct experiments.

The instruments Millikan later used for experiments were quite crude, and it took him two years to build them.

Observing with this set of instruments is also troublesome. Sometimes it takes five or six hours to observe just one oil droplet.

It took Millikan seven or eight years to complete the oil drop experiment - and there were two huge flaws that were criticized by later generations, and were even used as negative teaching materials by many big shots.

Because Millikan actually ended up with more than 140 sets of data, but he only selected 58 of them when submitting his report.

This is taboo in scientific experiments because it can lead to subjective assumptions.

As long as it is not a human factor, no matter how big the error is, you should accept it. This is an experiment.Millikan deleted data that he felt were too inaccurate.

Afterwards, Feynman strongly criticized this matter, claiming that there was no scientific spirit at all.

It can be found that many people have repeated Millikan's experiments since then, and the results are only slightly different from his. Everyone feels that Millikan is the authority, so they will modify their own data.

This is a very bad start for experimental physics.

Feynman directly called this approach "stupid science" in his 1974 Caltech graduation ceremony:
"From past experience, we have learned how to deal with some situations of self-deception. For example, Millikan did an oil drop experiment and measured the charge of electrons. His data was a bit biased because he used a different Accurate air viscosity coefficient.

Therefore, if you sort out the data obtained after Millikan measured the charge of electrons, you will find some very interesting phenomena: plot these data against time into a coordinate graph, and you will find that the numerical ratio obtained by this person is Millikan's value gets a little bigger, and the next person gets a little bit more data, and the next one gets a little bit bigger, and finally it stabilizes at a larger value.

Why didn't they figure out at the beginning that the new value should be higher? ——This incident makes many relevant scientists blush with shame——Because obviously the way many people do things is: when they get a result higher than the Millikan value, they think there must be something wrong, and they will search desperately, And found the reason why the experiment was wrong.On the other hand, when they get results similar to Millikan's, they don't review them so carefully.Therefore, they excluded data that were said to be too different from each other and did not consider them.We now know the tricks so well that we never make the same mistakes again.

During the war, there were some natives in the South Pacific who saw planes landing on the ground and unloading bags of goodies, some of which were given to them.They still hoped that the same thing would happen in the future, so they laid an airstrip in the same place, lit fires on both sides, built a small hut, and sent people to sit there with two pieces of wood tied to their heads (pretending to be earphones), inserted a piece of bamboo (pretending to be an antenna), thinking that this was the navigator in the control tower - and then they waited, waited for the plane to land.They were called idiots, they did everything right, everything looked the same, and it looked like it was during the war; but it didn't work: the plane never landed.This is why I call this kind of stuff "coot science", because they completely adopt the appearance of scientific research and everything is very similar, but in fact they lack the most important part. "

What Feynman said was serious.

Not only that, but there was another thing that made Millikan's oil drop experiment quite unpleasant.

When doing experiments, Millikan only acted as a mentor and proposed ideas. The person who actually conducted the experiments was one of his graduate students named Harvey Fletcher.

Unfortunately, the final report was signed only by Millikan himself.

Anyone who has been an engineering graduate student must understand that graduate students and instructors do experiments together, and those who do the experiments are graduate students.The tutor basically just proposed a topic, which was especially true in the United States back then.

At this moment, Li Yu saw the busy figure of 23-year-old Fletcher in the laboratory and sighed deeply.

Think of Lorentz and Feynman, Lord Rayleigh and Ramsey, they are great stories in physics.

Think about Fletcher who worked as an assistant to Millikan and Wu Youxun who worked as an assistant to Compton in the United States. They are really different!