Scientists are working in order to find how does this universe appear? How does it exist? How large is it? They are using theories such as Quantum theory to reveal these matters. According to most of the scientists they believe that the universe was originated according to the big bang theory.
Big bang theory helps us to understand a one scientific way that could happen at the beginning of the universe. But before this theory ancient astrologists express various ideas about the beginning of the universe that is different from the big bang theory. According to the researches conducted by Sir Edwin Hubble, he certifies that the universe is expanding. This result was a port key to the scientists who were trying to unveil the truth about the beginning of the universe. They believe that early universe was a place with a high density and high temperature.
In 1940’s physiologist George Gamow and his crew with the help of two physiologists named Ralph Alfer and Robert Herman proved the there was a bang at the beginning of the universe. In 1950 British scientist Fred Hoil named this as the Big Bang. According to the latest calculations this explosion was happened about 13.7 billion years ago. In 1950’s American astrologist William Flower and his team prove that elements with small atomic mass such as hydrogen, deuterium and helium were the main reason for the big bang and to the beginning of the universe. Heavy elements such as iron originated after them.
Now scientists have discovered that there are elements which are heavier than helium and lighter than iron in the middle of active stars. So it gives us evidence that at the beginning of the universe there was a kind of process that is proceeding in the middle of an active star.
In 1940’s some scientists believe that universe doesn’t change and it is steady as it is. But this was by the discovery of a quasar group of galaxies found by Martin Schmidt in 1963 who is a Danish astrologist. Quasars don’t exist near to the earth. They are far away from our solar system. Scientists believe that quasars are originated just after the big bang. However in 1965 Robert.W.Wilson and Arnopensia discovered a radio signal coming from the open space. It was a same signal from all the way through the universe and they proved this kind of radio signals are originated from an explosion with high temperature and high density. According to these results, scientists believe that momentum after the big bang universe was born and the radio signals released from this explosion are now spreading through the universe.
The heat generated from the explosion could be billions of degrees. But after the explosion within less than one second this system starts to cool down. In this moment electrons could be generated. Within a one second protons were generated and within the next 1000 seconds elements like hydrogen and beryllium were originated. Then there were many changes occur in the universe in the next million years. Before this time photon were unable to pass through matter without colliding with electrons, but after helium was born photons able to do that.
Anyway now it matter to scientists whether this universe is going to collapse or will it exist as it is in the present. If universe is going to collapse, there must be a high density so the distance between galaxies should be reduced. So scientists are searching whether the distance between space objects are increasing or decreasing. But they have only found that universe is always expanding. So it means that the first process after the explosion is still going on.