Question

what do you mean by the theory of big bang?

Answer 1

The Big Bang Theory is the leading explanation about how the universe began. At its simplest, it says the universe as we know it started with a small singularity, then inflated over the next 13.8 billion years to the cosmos that we know today.
The Big Bang theory is an effort to explain what happened at the very beginning of our universe. Discoveries in astronomy and physics have shown beyond a reasonable doubt that our universe did in fact have a beginning. Prior to that moment there was nothing; during and after that moment there was something: our universe. The big bang theory is an effort to explain what happened during and after that moment. 
I hope dis helps u..

Answer 2

Hi friend,

According to me a theory in astronomy ; the universe originated billions of years ago in an explosion from a single point of nearly infinite energy density ------compare steady state theory....i hope it helps you

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