It is generally accepted the theory means this:
This is nothing even approximating the notion of the Big Bang.
To begin with, you've failed to understand that
space itself was what expanded immediately following the Big Bang, not merely the material in the universe.
Where did the Big Bomb come from?
The Big Bang was not the explosion of a bomb, it was the expansion of space from an incredibly small area. Not just everything in the universe, but the
space of the universe, as well. Not just the space of the universe, but the time as well, because the Big Bang is the origin of spacetime.
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