Believe it or not there are no crazy explanations as far as I'm concerned...it's all science...and in science it's either this or it isn't...and by science I mean mathematics...Cuz science, chemistry, biology, astronomy are all maths...You're gonna tell me now that maths are a man-made conceivement and hence it might be inadequate in explaining the universe...WRONG...maths are a universal language and maths would still be there explainig how the universe works with or without us being aware of it......Using maths,Carl Sagan, a famous astronomer said that a galaxy the size of ours could accomodate a million sentient lifeforms other than us...
So the Big Bang is the theory that explains it all...simply cuz maths confirm that...and so far we are fully aware(well scientists are not me) of the universe's history...except for a tiny fragment of 0,00000000000000000000001 secs(that's 23 zero's so you dun need to count) right after the Big Bang which is a separate Era of our Universe...It's that way cuz it can't be any other way...
You may want to imagine that the whole universe is a lab experiment of some super race...but if the maths don't add up then that simply aint the deal...And even if that IS the deal...then that super race would have to obey to the rules of maths,too...
Now if that's how it works then how come we dun know everything there is to know about the universe? Simple...cuz we dun know everything there is to know about maths! Which means that all the crazy stories we may come up with may be ok to share around a campfire under the stars but that's all...
My english definitely isn't as good as it should be for me to make my exact point but hopefully you can follow where I'm going...