But Planck was a very understanding person. He said: "I myself feel that there are many loopholes in quantum theory that need to be filled. Why do you just use it as a basic hypothesis?" Li Yu said: "The emergence of new theories should have many holes. It needs to be improved, but I think the word 'loophole' the professor said is biased. It should be said to be 'supplementary'." Plank said: "Aren't loopholes meant to be supplemented?"
"Well, that's what I meant, but I can't say it that way." Li Yu said. Planck said: "Not only physics, but I also recognize your mathematical ability. According to the mathematical deduction method, only something that is completely correct can be used as axioms to deduce the following theory. Now quantum itself is a hypothesis, how can it be As a basic hypothesis?" Li Yu said: "It's just that we are doing experiments now. There is no problem in doing experiments with a basic hypothesis. Isn't this experimental verification?" Planck felt that what Li Yu said made some sense. After all, If you think about it carefully, even if it caused an uproar in the academic world, the volatility theory exists as a backing. At worst, it will be explained by the wave theory.
Because everyone's inherent impression at this time is that light should be able to interfere, because it is a wave.
Li Yu actually had this idea to some extent, and it was not easy to see the essence of the experiment. Although this experiment is now sensational, it may not actually affect many people. The only person it can really affect is Einstein, a temporary worker in Switzerland.
——This is what Li Yu's purpose is. The experiment was done for Einstein. At that time, through the explanation of photoelectric efficiency, it can be called a two-sword combination.
Because after the particle nature came out, in order to match the wave nature, the double-slit interference test of single photons was almost what everyone expected.
Otherwise, if a photon does not exhibit volatility,
"Wave-particle duality" has no real meaning. This is the theoretical and logical closed loop. The idea is: now we have the wave theory of light, → Einstein’s photoelectric effect will reveal the particle nature of light, → the single-photon double-slit interference test will further prove the wave-particle duality.
It's just that Li Yu slightly reversed the last two steps. By that time, after Einstein proposed the photoelectric effect, Li Yu will probably be busy again, and there will still be many experiments to be done.
Because in actual history, after Einstein proposed this theory, no one paid much attention to it for a short period of two or three years.
Some experiments must be relied upon to continue to confirm. After all, wave-particle duality is a super new theory that is very, very disruptive to today's physics community.
Li Yu thought to himself that he had to continue polishing his little experimental skills quickly. ——This is the case with physics in the microscopic field. After a theory is formulated, it will not work without experiments. No one can fully believe it.
It’s just that from then on, the status of theoretical physicists really stood up, and was not just a appendage of experimental physicists.
Theory can also guide the direction of experimentation. Instead of existing experimental phenomena in the past, the theoretical physics community seeks explanations.
Carl Siemens was listening to the exchange between the two great masters. He was also a little confused, so he asked: "Photons? I have heard of stones? So, light is like stones?"
"Although this metaphor is very inappropriate, Mr. Siemens can understand it this way for the time being." Li Yu said.
Carl Siemens said: "If you understand it this way, if you throw the stones one by one through the two slits, it will definitely interfere, right?" Li Yu said: "They will only form two piles of stones." Carl Siemens said: "This is in line with common sense! I also agree with what Mr. Planck said. The single-photon experiment you proposed can only have two bright spots at most." Carl Siemens said it more simply. Planck added: "I still think, If photons really exist, then there will be no interference if they pass through the double slits one by one. Interference requires at least two photons to pass through at the same time." Li Yu said: "No, even if the photons pass through the double slits one by one, there will still be an interference pattern." Planck said: "Is a photon interfering with itself? It's illogical!" Li Yu said with a smile: "We will know after the experiment is done." Planck said: "Okay, I will wait and see." Li Yu knew Once you do it, it's just the beginning.
After that, experiments need to be done to continue to prove the particle nature of photons, so that they can continue to support their own experimental results.
This is how the development of quantum mechanics is built step by step. As for the theory of relativity, Einstein basically figured it out all by himself.
Li Yu has already made a lot of initial preparations at home, and it will be very fast to continue the experiment at this time.
The key point is that the test equipment provided by Carl Siemens is very complete and advanced. It is worthy of being a German laboratory, rigorous and meticulous.
Lu Bicheng looked at Li Yu and didn't dare to say a word. She just thought in her heart that when he was serious, he had a strange and indescribable feeling.
It takes many days to do the experiment, and Li Yu will definitely be bored in the laboratory during this time. Lu Bicheng asked carefully: "Do you need my help?" Li Yu said: "No, I have made all preparations." Lu Bicheng whispered: "Okay." Li Yu was a little embarrassed to let her stay for the experiment. room, so he said: "You can walk around, Berlin is quite beautiful and spectacular." Lu Bicheng shook his head: "I don't speak German." Li Yu said: "Germans can speak some English, and they can always touch There are a few who can tell you better." Lu Bicheng shook his head again: "I don't know anything about Germany, and I won't go anywhere." Li Yu said, "Okay, to be honest, I don't want you to run around. Nowadays, we don’t have mobile phones or navigation. It’s unimaginable if something goes wrong.” Lu Bicheng’s eyes flashed: “You also want me to stay in the laboratory?” Li Yu nodded: “This is indeed safe.”
"Then I'll stay here!" Lu Bicheng said happily,
"Also, what do you mean by 'collection' and 'Taoism' you just mentioned?" Li Yu explained casually: "It is - collect some foreign books and show them to you so that you can improve your literary accomplishment and Taoism. "Then he continued: "I almost forgot. Let's go to the bookstore first and buy some English versions of Mr. Tolstoy's works, as well as Andersen's fairy tales and Grimm's fairy tales, which will be enough for you to read for a while." Li Yu was in the 21st century in his previous life. , the popularity rate of English in Europe is already high.
Generally speaking, people from all over Europe can speak a little English. Even the very arrogant French have a higher English penetration rate than Italy and Spain.
The British... seem to only speak English. But today, the English penetration rate among the general population in European countries is obviously not as high as that of later generations. Those with multiple language abilities are highly educated.
Berlin is a big city after all, so it didn’t take much effort to buy the English versions of Toon’s complete works, Andersen’s fairy tales and Grimm’s fairy tales.
It took Lu Bicheng a long time to look at it. The key was that she also wanted to translate two sets of fairy tale books. This was a big project and she would definitely be busy.
The laboratory that Carl Siemens gave Li Yu and Planck was indeed not small, with three floors and many independent bedrooms.
One of them was specially given to Lu Bicheng. Lu Bicheng looked at the books in front of her, clapped her hands and said, "I'm upstairs. Just call me if you need anything. I can take care of you. I know you are very busy and tired." The woman's thoughts are still very delicate, she can tell Li Yu didn't seem to have any intention of playing around for the time being.
Although I didn't know why he kept himself so busy, I didn't ask any more questions. Planck, who was also in the laboratory, smiled and said, "I told you to take more care of him." Lu Bicheng quickly said, "The care I am talking about is... yes... ah, I mean cooking for you two." Planck said: "This is great! If there were delicious Chinese food, I would have no problem living here and not going back to the University of Berlin." Li Yu said with a smile: "It's a pity that Germany doesn't have many condiments, so we can't Bring out the true strength of Chinese catering.”
"Condiments?" Plank said,
"Isn't the sauerkraut enough?" Li Yu almost fell over. It's like being in Korea!
"I mean onions, ginger, garlic, pepper, aniseed, star anise, cinnamon, soy sauce, vinegar, etc." This time it was Plank's turn to be surprised: "Chinese people need so many things to cook? It's too complicated. Right! Even if you study in the school for many years, you may not be able to master it." Li Yu smiled again: "You are really right, there is a special cooking school." Plank said: "I have decided. I have to eat Chinese food here for three meals a day!" Nowadays, China does not have much cultural export, and catering is indeed a very good pioneering card.
Once you've settled in, it's time to start experimenting. As you can tell from the name of the single-photon double-slit interference test, the key lies in how to control the appearance of single photons. That is, one photon passes through the double-slit device and reaches the photosensitive screen before another photon is emitted.
It sounds difficult, but in fact the principle is not complicated. To put it simply, it is to reduce the light intensity.
When the light intensity drops to a very low level, a single photon will appear, and then calculated based on the frequency, it can be ensured that exactly one photon passes per unit time.
This light intensity is very weak, almost equivalent to the candlelight of a candle viewed from a distance of nearly 2 kilometers.
After a long exposure on the last photosensitive screen, individual small light spots will appear. As the number of light points increases, the famous light and dark stripes will appear.
In fact, the appearance of the light spot itself can be regarded as a hint that light has particle nature. The experiment needs to be done many times to get enough photos of the process.
As for the final paper, there is no need to explain too much. Li Yu just borrowed the inspiration from the previous correct derivation of Planck's black body radiation formula and once again used the quantum theory in it to extend it.
From a feeling point of view, the paper itself is a bit
“No harm to humans and animals” should not attract much opposition.
