I Am An Atheist! Ask Me A Question!

[Darwinian]

explain scientifically what start the universe ?

I'll keep it simple for now but may elaborate later, or others may.

1) Nothing started the Universe because in order for there to be a beginning there must have been a time before. As not only matter and space was created at the big bang but time itself there could not have been a before and so there could have been no cause.

ok back to darwinian explanation , matter, time and space created at the big bang.
so whats the difference between a man saying god create everything and a man saying big bang created everything ?

Because to claim that a God created everything requires an extra step. Who created God? If the answer to that is that God has always existed why not just save a step and say the Universe has always existed, in one form or another.

There is no reason for a God. Nor is there any evidence. The Universe looks and behaves exactly as it should if there were no God.