Question

I do not believe in any theory about the origin of the universe because

Answer 1

cause at that time , no one was there to see it lol ...

but just like you , I have doubts in big bang theory , till now we have only approximated about that particular thing , but universe is expanding and it maybe because the force created at the time of big bang and the force is moving space away and away , but there can be more possibilities too other than just big bang , but the only thing lacking is imagination (^^) ....