The Big Bang theory doesn’t necessarily entail that there was a “beginning”. There is a theory that after expanding for a long time, the universe once again starts to contract and eventually contracts back into a tiny little pinprick which contains all the matter in the universe, which after another unimaginable period of time explodes outwards again with a big bang and starts the entire process over again.
The Big Bang theory, however, has plenty of facts to support it. That’s what a scientific theory is; a collection of demonstrable facts and observations that support a given conclusion. Theories can be modified when new information is presented but that doesn’t mean that the current theory isn’t made up of facts.





