Astronomy – our picture of universe

Astronomy – our picture of universe

        Earlier people had a different picture of the universe. People believed that earth was flat in shape and was never circular but with the development of science and technology, and especially physics, we come across many answers about the universe. 

Theories of great scholars:

        Aristotle in his book “On the Heavens” discussed two basic arguments:

1. He comes to know that the eclipse of the moon was because of the arrival of planet earth between the sun and the mood.

2. The North Star appeared lower in the sky when seen from the southern side.

       

        Aristotle believed that the earth was stagnant and the moon revolved around it but it was in the second century AD. The complete model was built with the name of five planets.

1. Mercury

2. Venus

3. Mars

4. Jupiter

5. Saturn

      It was in 1514 that Nicolaus Copernicus for the first time said that

“Sun is stagnant and all the other planets revolve around the sun”

But after hundred years two scientists Kepler and Galileo supported the idea of Nicolaus Copernicus. Later on science started developing and in the year 1687, Sir Isaac Newton gave us the theory of the law of gravitation. According to his law it is gravity which makes the moon revolve around the earth. Gravitational force has also effect on the movement of stars and its infinity and therefore it is impossible to have a static model of universe. 

         Because of the development of science, people come to know about the general climatic of the earth and the universe as a result the entire universe was now no longer a big question. Most of the people believed that the universe is unchanging and static. But in the year 1929, Edwin Hupple found out that the galaxies are gradually moving away from us which later on gave us the big bang theory. Therefore people started believing that there are physical reasons of the beginning of the universe, and it is not God who was instrumental in creating the universe. 

      One cannot perhaps know about the universe and the end of it, as any theory is provisional and therefore hypothetical. According to Carl Popper,

“Any good theory is an outcome of multiple observations, and the goal of science is to provide a single theory for the understanding of the entire universe.”

      But it is very difficult to do that because observations change from time to time and as a result coming to a final conclusion is almost impossible.

Theories of universe:

Scientists, today explain the universe in two basic theories,

1. The general theory of relativity

2. Quantum mechanics and physics

      The theory of relativity describes the gravitational force, quantum mechanics and physics talk about the smallest phenomenon of the universe.

      Physics today is in search of a new theory which can accommodate all the above mentioned theories as all of them are partial in nature.

      To discover the complete unified theory is an extremely difficult task and people are still trying to search the perfect answer for all the questions in relation to the universe.