Not only is it a fact that there is no evidence...(that there is or ever could be a god, I assume is meant), it is also a fact that any God, in order to exist, would be in breach of all the laws of physics"

Would it be more accurate and reasonable to say "under the Laws of physics, as we understand them today"?

If it is a fact (that no god exists), can it be proven to be so?

Most would likely cooose to say it is probably a fact (as noted below), given current science understanding, not that it is a fact...that can be seen as stating that it is known beyond any probability?