The Egyptian cult in Heliopolis has one of the best creation myths I think
But still, what is todays scientific fact may be tomorrows scientific fiction, the big thinkers don't always get it right, some of Einsteins theories are being questioned today IIRC. However, whether it was the work of a God, an alien being or scientific process no one will know for certain, it will be one of those unanswerable questions short of some divine intervention or human mental transcendence.
Personally, I think this universe was created by the collapse of the one before us, and so on and so forth back until the first universe...but the billion dollar question is, what started THAT universe.
We'll never know.