Source : Black Hole
In the meantime, the world seemed to be flat in Greece. Naturally the top-bottom idea was the absolute one. It was then thought that objects or animals were heavenly, above their position, in heaven. The objects that are not heavenly are in the ground or in the footsteps. Throwing things which are not heavenly, they come back to Earth once again. Then one time the evidence is that the earth is not flat, round. Then the theory of over-under agony broke.So the previous idea about the declining material is not exist at all. The reason why throwing objects around is to return to the world again, its new solution becomes necessary.



Source : Claudius Ptolemaeus (Ptolemy)
Then Aristotle patchwork made an explanation. That is, The world is the center of the universe. All planets in the sky are rotating around the earth. The motion of all the objects so towards the center of the world. For this reason, throwing the object upside down, it returned to Earth. Aristotle's influence in the knowledge of science at that time is widespread. Everyone accepted the theory of Aristotle's without confusion. Later, in the first century of Christianity, Ptolemy set up a model of a philosophical universe. It is in line with Aristol's opinion.In the Ptolemy model, the universe is divided into several layers. Its center is in the earth. Surrounding the Earth, the moon, Venus, Sun and Mars respectively. They all have the same straight line. Other groups were not yet discovered. So they did not replace Ptolemy's model. There are other stars in the sky at the outer stage at the outer level around the earth. Seeing that model of Ptolemy, a baby laughing at the first shake of today. But the people of the whole world accepted the model during that time.



Source : Ptolemy Model
There was a rift in the sixteenth century. Polish historian Nicolas Copernicus said Aristotle's doctrine is wrong. He said, not the sun, but the earth rotates around the sun. Copernicus wrote a book with a detailed explanation. The book was printed on the eve of his death. But nobody believed Copernicus.


Tyco Brah was a Roman mathematician of the second Roman Emperor of Prague. Emperor Astrologer He did a lot of work with space stars.Tycho's assistant was Johan Kipalar. After Tycho's death, he was appointed as the emperor's mathematician and chief minister of the Astrologer. In the meantime, the main task of the astrologer is to predict the fate of the emperor, to see the direction of the stars, advance the state's good news. Not to say, these astrologers in the country were the chief ministers of kings and kings. They used to guide the kings in the wrong way. The untimely demeanor of the subjects came down due to the burgeoning of the astrologers.


Kepler was quite different. He had no interest in future counting. Yet, on the request of emperor, he used to calculate some. But he admitted that there is no miracle in this world. Some predictions were used to understand the mood of the weather. He said to the king, there was no need to be an astrologer . Anyone who has a little knowledge can do this. King Rosaloff did not torture Kepler. Kepler was his teacher. He did great respect to Kepler Kepler believed in the concept of Copernicus.It is against Catholicism. Nevertheless, king Rodaloff did not obstruct him. The king was not blind faith. He wanted Kepler to be employed as a mathematician in the rank of mathematician, and he used to apply for the spread of knowledge. Kepler had the freedom, he practiced astrology. The study of the planets and stars was also carried out. But he did not have any good telescope.


At that time Galileo's huge named was in Italy. He has responded to the whole world by creating various instruments. His biggest discovery was the telescope. Previously there was no telescope, nor was it a telescope. But there was no telescope near Galileo, and no one else's telescope. Galileo sees the sky sculpted with telescopes. Then announced that Copernicus was right. Galileo was not as fortunate as Kepler was. The emperor of Prague was not as great as the Roman emperor. Apart from Rome, the Vatican of Pope's.Their words are the god words in Italy and Europe. There was no one in Italy who had opposed the Vatican. Christianity could not actually go beyond Aristotle's mind. That was why he had to suffer untimely torture. Kepler then showed how, on which way the earth and other planets around the sun are turning around. He also discovered the mathematical formula for the way of the planets.


Why the planets revolving around the sun. Why not run out of the eternal space? He could not solve this question. The solution came in seventeenth century. Hold Newton's hand.



Source : Gravity. It isn't just a good idea. It's the law.
Newton showed that the earth around the sun did not flutter like that. They have an invisible force of attraction inside. The name of that attraction force is called gravity or gravity force. The gravitational force acts not only between the sun and the planets, but in every object of the universe.


Newton gave a formula for the gravity force . That is, every object in the universe attracts each other. The value of this attraction force will be as much as the mass of masses is greater. Gravity increases the quality of the gravity if any one's mass increases. But the distance between the object increases as much as the gravitational pull in them decreases. This decrease is not easy again, in square. That means if the distance is doubled, then the value of the epic force decreases to a quarter of the previous standard.


In the world, we are walking and moving, there is no substance going away from the surface of the earth, because of its gravity. Newton showed that the gravitational force only attracts, never repels, nor ever.
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(To be continue...)

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Check other parts of this Series here:

1. Black Hole-1 : History seen back

2. Black Hole-2 : Gravity Background

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