How did the Universe begin?
When did the universe begin?
There is no other scientific question which is more fundamental than this. Nor can any other question trigger such a potential debate within the researchers worldwide. Humanity has been theorizing about the origin of the universe since ages. However, the subject of the origin of the universe is still a very controversial matter. Mankind is still researching for the signs of its origin. As no one is there when the universe began to support any theory associated with it. In such a situation the best answer with the scientists can come across through must be the most infallible theory that can reinforce all the observations for the universe. But till date, no explanation has come up to explain all the observations. Evidence suggests that the universe started around started around 15 billion years ago like a dense balmy bubble of gas (hydrogen and helium only) expanding swiftly outward.It is assumed that when the universe is 100 million years old the first star was probably evolved. That explains the age of sun which was assumed to be evolved about 5 billion years ago.

There is a lot of theories of how it (the universe) actually started. The Greek philosopher, Aristotle, and his associates believed in the universe were static and unchanging with time. Now, the leading theory of the origin of the universe is an event as Big Bang. Although there are mixed reactions from the scientists still this theory is widely accepted by widely accepted by scientists. This theory was made by the facts we have today about universe origin.

This idea actually came when Einstein Hubble observed that galaxies are speeding away from us, that also in all directions as if they have been propelled by a force. In theory, it is clarified that in the first 10-43 seconds of its existence, the universe was very compact, and four fundamental forces of gravitational, electromagnetic, weak and strong nuclear forces were compressed into a single force. Then in an unthinkable small fraction of seconds, all the matter and energy expanded outward more or less evenly. After inflation, the universe is still expanding but obviously at a much slower rate. It is still unraveled what exactly lowered inflation which may explain why the universe has such as even temperature and matter distribution.

At the aftermath of cosmic inflation, the matter cooled down and more various kinds of particles began to form and they gradually condensed to form stars and galaxies of our night sky.

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