Lin Ping arranged the experimental equipment, and what he wanted to do was a very simple physical experiment, double-slit interference experiment!

This is also a physics experiment that has not been reasonably explained in the physics community so far, and it is also called the most bizarre physics experiment.

The equipment for the experiment is very simple: a flashlight or a candle, a wooden board with two gaps opened.

"Come on, block the window! Let the classroom fall into darkness!" Lin Ping said with a smile.

So the students quickly found something to block the small window of the dirt house classroom, closed the door of the classroom, and the classroom was in dim light.

"Students, look, there is a wooden board on the table now, and I have two gaps separated by this cardboard!" Lin Ping raised the flashlight, "If I use the flashlight in my hand to shine this wooden board, what will appear on the wall?"

Liu Xiangqian raised his hand: "It must be two traces of light!"

Liu Weiguo said: "I think it's one."

"Are you stupid? There are two cracks, but how could there be only one light mark!" Liu Xiangqian retorted dissatisfiedly.

Liu Weiguo shrugged: "I feel that it may merge!"

"Okay, classmates, it's time to witness the miracle!"

Lin Ping opened the old-fashioned iron flashlight in his hand with a "pop", and the beam of light passed through the two gaps in the wooden board, and then the students glared in surprise and opened their mouths.

The light on the wall is neither one nor two, but many, and countless, distributed regularly and spaced from the middle to the sides, and gradually darkens from the middle to both sides.

“1…2…3…”

The students began counting the light stripes on the wall.

"Oh my God, 8 lights, why are there so many?" Li Shulin said in surprise.

"No, right, it's nine paths. Look at the corner of the wall, there is one path, but it's not obvious." Feng Xiao said.

"It's ten! Why do I feel that the corner of the wall should be two overlapping together!"

The students began to argue about how many streaks of light were on the wall.

"Isn't it very magical?" Lin Ping said with a smile.

"Yeah." The students nodded.

"Then this is not the most magical place!" Lin Ping said with a smile, "I'll ask you a question now. I'll say that Liu Xiangqian is both a boy and a girl, do you believe?"

The other students burst into laughter: "Don't believe it!"

Liu Xiangqian curled his lips and said, "Teacher, I am a man!"

Lin Ping thought for a while and said, "Then I said I am both dead and alive. Do you believe it?"

The six students below shook their heads collectively.

Liu Qingmei pouted and said cutely: "Teacher, I'm timid, don't scare us!"

Lin Ping laughed twice and said, "In the history of physics, scientists have been arguing about one thing that is whether light is a wave or a particle..."

Then Lin Ping explained to the students the difference between waves and particles on the blackboard.

"In the end, the physics community finally reached a consensus that light has wave-particle duality. In layman's terms, it is both a wave and a particle!" Lin Ping said.

The children looked at Lin Ping in surprise: "How is that possible?"

Lin Ping smiled and said, "It's true that light is both a wave and a particle! It has both a wave and a particle! If you have to make a metaphor, it means that Liu Xiangqian is both a man and a woman. He has both a man and a woman's bisexual characteristics!"

"Ah, teacher, I am a man, I am a man! Not a woman!"

Liu Xiangqian wailed and protested, and the others laughed.

"Okay, now let's go back to the experiment we just did. This experiment is called the double-slit interference experiment. It proves the fluctuation characteristics of light. Because light is a wave, it interferes with each other and forms several streaks of light on the wall." Lin Ping said.

"However, light is also a particle, so scientists use this device to see how light passes through these two gaps, so they began to observe further. What the teacher here wants to say is that not only light has wave-particle duality, but now the physics community believes that all matter has wave-particle duality. However, the fluctuations of macroscopic objects can be ignored, and elementary particles such as protons and electrons in microscopic objects also have wave-particle duality. In order to facilitate experiments, scientists conducted further experiments with electrons."

Lin Ping popularized basic knowledge concepts such as protons and electrons on the blackboard.

"So, scientists decided to let electrons pass through the double slits one by one. Now we assume that the two slits are not electrons but rice. What do you think will happen? Will this kind of interfering stripe on the wall be formed?" Lin Ping said.

The students thought and shook their heads.

"No, teacher, the probability of rice passing through these two gaps is random, and the location where they drop is also random." Liu Qingmei said.

"Yes, Liu Qingmei is right. When we have time, we can also do an experiment where rice passes through two gaps. However, after the rice is replaced by electrons, one by one, one by one hits the wall through the gap, such interference fringes still appear. At the beginning, we used a large number of electrons, which is similar to the light in a flashlight. Each electron interferes with each other and forms a stripe."

Lin Ping Jixue said, "However, one by one still forms interference fringes, which means they interfere with themselves! Just like Liu Xiangqian originally walked through the front and back doors of our classroom, it was random. He was willing to walk through the front door and the front door, and he was willing to walk through the back door. However, there were still interference fringes on the wall, which means that Liu Xiangqian walked out of the front door and the back door at the same time, interfering with himself, forming stripes."

The students frowned incredibly.

"Isn't it incredible? But this is not the most incredible!" Lin Ping said with a smile.

The students were so surprised that they couldn't speak.

"Scientists decided to observe how a single electron passed through the gap. Is it divided into two? Or is the first Liu Xiangqian walking on the front door, and the second Liu Xiangqian automatically walked on the back door? So the scientists installed a detector in front of the double slits, which was similar to a camera. They decided to take a picture of how Liu Xiangqian walked, whether to walk on the front door or the back door, or to walk on the front door in two!" Lin Ping said humorously.

The classmate laughed, and Liu Xiangqian also touched his head and laughed.

"As a result, something magical happened. When the scientists made observations, the interference fringes on the wall disappeared! It disappeared! There was only one light on the wall! In other words, Liu Xiangqian did not interfere with himself, he honestly walked only one door!" Lin Ping said in surprise.

And the students were really surprised and opened their mouths wide.

"And when the scientists evacuate the observer, the stripes on the wall are restored! It's like the electron knows you're observing it, so it doesn't tell you how it goes, and when you don't observe it, it starts to play with it." Lin Ping said.

Wang Yige said at this time: "Teacher, is it because of scientists' observations that affect electrons?"

"Yes, scientists also thought so, so they decided to move the observer forward from the double slit to the double slit. That is to say, I moved the camera that observed how Liu Xiangqian walked out of the classroom door from the classroom to outside the classroom. When you, Liu Xiangqian walked out of the classroom, I suddenly turned on the camera, so that you can always catch you!" Lin Ping said humorously.

"This is also called a delay experiment, so scientists did it. When the electrons passed through two slits and became an established fact, the scientists opened the detector instantly, but found that it immediately changed from passing through two slits to passing through one slit, and the interference fringe disappeared, leaving only a light spot on the wall. In other words, the scientists' delayed observation changed the established fact! The entire causal relationship was reversed!"

"This is equivalent to Liu Xiangqian having walked out of the classroom through the front and back doors at the same time. As a result, delayed observation has changed the past movement trajectory that has become a certain fact. He no longer walked out of the front and back doors at the same time, but just walked out of one door."

Lin Ping's words immersed the students in surprise.

"This phenomenon has not been given a reasonable explanation in international physics so far. Even if the observation level continues to improve, it is still impossible to find the reasonable cause of this phenomenon." Lin Ping thought for a while and said, "This is equivalent to seeing that the flower is a flower when you open your eyes, and when you close your eyes, it is not a flower. The moment you open your eyes, it returns to a flower."

"Of course, the teacher's knowledge is also very shallow. I hope you can study physics well, then find reasonable and convincing answers for this experiment, and then turn around and answer the teacher, okay?" Lin Ping said with a smile.

[System: Your student Wang Yige is now very interested in physics, and his thinking ability is further improved!]

[System: Your students Liu Weiguo, Liu Qingmei, Feng Xiao, Liu Xiangqian and Li Shulin have developed a great interest in physics, and their enthusiasm for learning physics has been improved.]
Chapter completed!