Don't doubt that the gravity push me to you!

Have you ever heard the song "Gravity"? In this song, Wang Suzhen sang, "I said something is called a kind of gravity. Because you start to believe, those principles ..." In this song, the gravity is a kind of emotional gravity, but in real life, it is in real life. But omnipipiporous.

How much gravity knows

When it comes to gravity, people always think of the story of Newton and apple trees. The full name of the gravity of all gravity is a law of gravity, which is a law of interaction between objects. Its proposal is a great progress in the history of human science. It not only explains many physical phenomena that could not be explained before, but also opened the door of many unknown fields.

In 1687, Newton first proposed the law of gravity in the book "The Mathematics Principles of Nature Philosophy" he published -it was attractive between any objects. The square is inversely proportional to the square. If the quality of the two objects is represented by m₁ and m 个, R represents the distance between them, then the attractiveness between objects is, that is, gravity is equal to gravitational constant (G) multiplier with the quality of the two objects to remove the square of their distance. Gravity constant value is about::

It was measured by British physicist and chemist Henry Cavendi.

Newton and its works "Mathematics Principles of Natural Philosophy"

(Picture source/Wikipedia)

The discovery of all gravity is one of the great achievements of natural sciences achieved in the 17th century. It unifies the laws of object movements on the ground and the laws of celestial movement, which has a profound impact on the development of physics and astronomy in the future.

The gravity allows planets to use the law of the sun to use the law of gravitational movement around the sun in accordance with its own track, but also pointed out that Jupiter and Saturn's satellites also have the same exercise laws around the planet. He believes that in addition to the gravity of the earth, the moon is also subject to the gravity of the sun, which explains the two average differences and business trips that have been discovered in the moon in the moon. Later, scientists successfully predicted and discovered Neptune based on the law of gravity.

Why is there a gravity between objects

Although Newton's law of gravity explains the gravity, the tide of the ocean and the planet and the celestial body of the objects on the ground, unify the movement of the heaven and the movement of the planet and the celestial body. Failure to explain why the two quality objects are caused by gravity. This problem was solved by Einstein's general theory of relativity.

The law of gravitational gravity unify the theory of celestial movement and the on -ground object movement, and the general theory of relativity believes that a quality object will bend the time and space around it. In this bending time and space, all objects will naturally follow the ground line (also It is called the "short -range line") movement and manifested as closer to one. We can't see the bending of time and space. We only see that objects are moving closer to each other, and we think that there is a kind of gravity between them. In fact, this kind of gravity shown between objects is not a true force, but time and space Bending performance.

Time -time bending diagrams of four -dimensional space -time bending, we are unsatisfactory, but we can lower one dimension (on the two -dimensional plane) as an analogy. Imagine that there is a piece of cloth that hangs it in the air, and put a small ball on it, it will press the cloth and put a small ball in another place, and it will also press the cloth around it. We can see that these two small balls will naturally move closer to one, which is the result of them along the ground testing. We can't see the bending of the cloth, and only see that the ball is moving closer together. There is a gravity between them. In fact, it is just a manifestation of time and space bending. This explanation has been well tested on Mercury's recent advancement, light in the gravitational field, and gravitational red shift. After that, it has been further tested in a large number of more precise experiments, which is in line with the experiments that meet the experiments. Well. Therefore, the general theory of relativity is considered the best gravity theory.

The essence of gravity: time and space bending

In 1915, Einstein explained the essence of gravity in his general theory. He believes that the gravity does not realize the existence of gravity. Gravity is just an illusion. Its essence is that the quality is bent to the surrounding space -time. In order to verify Einstein's conjecture, at the end of May 1919, scientists used a full -fed food to conduct a famous star shift experiment.

During the full -day eclipse, people can directly observe the stars behind the sun; 1919 shot by British astronomer Arthur Endton

May 29th full food (upper right) (picture source / Wikipedia)

Under normal circumstances, the light emitted by the stars behind the sun will be blocked by the sun, but when a full -day eclipse, under the dim conditions, the light from the stars behind the sun can be passed on the earth after the sun gravity is deflected. Can directly observe the stars behind the sun. As shown in the figure below, the solid line is the trajectory of the light, and the dotted line is the virtual image of human observation of the stars on the earth. Using Einstein's gravitational formula, the data calculated by people is exactly the same as the results observed, and the partial folding angle and position calculated by the law of gravitational gravity of Newtonian are more than half of the actual data, and the error is large. Because of this, scientists believe that Einstein's interpretation of gravity is more scientific. But this does not mean that Newton's law of gravity is wrong -it only has a certain scope of application, it can only be applicable to a weak gravitational field, and it will fail in a strong gravity field. Since then, scientists have obtained more stars' shift data from daily food, which further shows the correctness of Einstein theory -time and space bending is the essence of gravity. This article comes from the magazine of "Knowledge is Power". The original title "Magic" is boundless. "

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