As soon as we arrived in the classroom, we heard two male students talking. One of the www.biquge.info said, "If I give birth to a boy in the future, I will definitely name him Su Song, so that the whole world will praise him." A boy said, "If I give birth to a boy, I will call him Shen Kuo, so that he will have the knowledge to cover all things in heaven and earth." "I was secretly shocked in my heart, these two names are really thunderous, famous. One is a famous scientist of the Northern Song Dynasty, this has profound attainments in engineering and astronomy, lasted several years, and finally successfully assembled a set of observation of celestial phenomena, calculation of time, reporting time in one of the functions of automatic astronomy, machinery, water transport instrument elephant platform, the first to use the escapement device, driven by water power, a day and night of turbidity rotation circle, every certain moment, there are wooden people come out to ring the bell and drum, report the time, indicate the hour, is the world's earliest and most magical astronomical clock. Another scientist, Shen Kuo, as his name suggests, is an all-round scientific genius who has excelled in astronomy, calendar, geology, optics, medicine, mathematics and other fields. He found that the magnetic needle was in the compass, slightly easterly, not all south. This is the world's earliest record of geomagnetic declination. He discovered that the Sun, Moon, and stars were spherical, and that the Moon did not emit light, and that its brightness came from the reflection of the sun's light. He also found that the smallest unit after cleavage of calcium sulfate crystals all have the same crystal shape, which is hexagonal and neat like a tortoise shell. His book "Dream Creek Writings" is even more well-known.

Historian Mr. Chen Yinke believes that "the culture of the Chinese nation has evolved over thousands of years and was created in the Zhao and Song dynasties. After fading, it will eventually recover. The Song Dynasty was the heyday of China's scientific development, and Joseph Needham, who wrote The History of Science and Technology in China, said: "Whenever one looks for a specific historical source of science and technology in Chinese literature, it is often found that its focus is on the Song Dynasty, whether in applied science or pure science." "In that era, if there was a Nobel Prize, the Chinese would win the prize. Therefore, if there was a Nobel Prize in that era, Su Song and Shen Kuo would definitely be able to win the Nobel Prize in Physics and the Nobel Prize in Chemistry respectively, would it be quite meaningful for us to educate these ancient Song Dynasty students? Regardless of whether these two names that popped out of their mouths were false or real, we all felt greatly encouraged.

Watching us stride in, the naughty students stopped talking to each other, and couldn't take their eyes off the one-person-tall globe that Xiao Fei was holding casually, which was really shocking and eye-catching. They flocked to us like a tidal wave and looked at us curiously.

There was a lot of discussion: "Brother Xiaofei, Sister Ziyue, what is this thing, is it for play?"

Xiao Fei asked rhetorically, "Excuse me, what do you think the place where we live is like?"

"My father and mother always told us that the sky is round. The sky is round like a cover, and the place is like a chess game (chessboard). So we inhabit a boundless square land. Everyone said in unison.

Xiao Fei smiled slightly, shook his head and said: "This is a globe, a shrinkage of the planet we live in, 71% of the earth is ocean, 29% is land, so the earth is blue from space, so it is a blue planet." The place where we live is a round water balloon. ”

"If the earth is round, why didn't we fall?" was a childish voice.

Xiao Fei touched the little guy's head appreciatively and said: "You think well, this is a very interesting question, which means that you have activated your little brain, first of all: there is no absolute concept of "up, down, left, right" in time and space, the concept of "down" is artificially prescribed, referring to the direction in which objects fall freely, and the opposite is up. Second, because of the mass of the earth, the surrounding space-time is bent, resulting in gravitational acceleration that always points from the ground to the outer space, which is characterized by the fact that matter is always attracted. Because of gravity, we won't fall. ”

The child nodded as if he didn't understand.

A child asked curiously, "Brother Xiaofei, what's the matter with the stars?" Can I pick it up and hang it at home?"

Xiao Fei smiled slightly and said, "In fact, the sparkling stars we see, in fact, its light is like a photograph, transmitting images at the speed of light. According to Einstein's theory, light travels in a straight line, the speed of light is 3.0 times 10 to the 8th power, the stars are very far away from the earth, and when the stars emit light, the light from there travels a long distance before reaching the earth. So most of what we see is what we see is the stars of the past. If there is a star 3 light years away, since you can see its image now, then it already shows that the image has been running for 3 years, it is already an outdated image, we are seeing the past, and we are really looking back at the past. Maybe many of the stars are gone, and we can't see our past, but we can see the past elsewhere in the universe. ”

One kid asked, "Do all the stars revolve around the Earth?" and he had a great ability to draw inferences.

Xiao Fei continued to say eloquently: "There is also the traditional geocentric theory that is wrong. We can't be presumptuous, think that we live on the earth, human beings are the spirits of all things, and take it for granted that the earth is the center of the whole universe, in fact, this is completely wrong, the sun is the center of the whole universe, which was first proposed by the great astronomer Aristarchus in the Greek period, that is, the earth is a sphere, and the earth is moving. The sun is immovable, and in the center of the universe, the planets revolve around the sun, developed and perfected by Copernicus, and in defense of this doctrine, the Italian thinker, natural scientist, philosopher and writer Giordano Bru was condemned by the Inquisition as a heretic and burned to death in the Piazza del Fiori in Rome. ”

Our expressions were solemn, and the little children looked surprised: "Is it important to revolve around the earth, or around the sun, and why does he have to pay with his life?"

Xiao Fei took out a small wooden globe made of small elaborate from the bag, and solemnly sent it to each child, saying: "So the truth is hard-won, and in order to pursue the truth, some people are willing to give up their precious lives, so you must study this hard-won knowledge." ”

Those children of the Great Song Dynasty couldn't stop looking at it like they had a treasure, and they began to talk like sparrows again, "It turns out that the moon is also a celestial body, Chang'e running to the moon is fake, and Wu Gang cutting down trees is also fake." "Why are there so many countries here? I really sit in a well and watch the sky, I don't know what about my country and some small countries around it? I didn't expect that there are so many different countries, so many different people, and the world is really colorful. "Brother Xiaofei, is that a black man? Oh my God, it's so black, it's like a piece of black coal." I have never seen such a black person, white-skinned, yellow-haired, but I have seen a few. "I think it's really because when our Nuwa Niangniang created people, they didn't pay too much attention, the heat was too big, so these Africans were scorched, and they were all black, and our Chinese skin is the best, the most careful when baking, the heat is just right, no more, no less, not big or small, so the skin color is the most beautiful." And those white people's words are not baked before they are baked, so they still need some heat. Everyone laughed out loud when they heard his immature words, and the class was full of laughter, like a sea of happiness.

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