Einstein said if you can’t explain it to a six year old, you don’t understand it yourself. And that sums up every person who’s ever talked about any kind of dimensions, string theory, and so on. They talk with contradictions and have explanations
Nearly 14 billion years ago, due to a random fluctuation in a completely empty void, a universe exploded into existence. Scientists call this the Big Bang theory for the origin of the universe. But there are other theories .