This illustrates one of the problems I have when secular people insist that things such as the theory of evolution or the big bang theory must be true and ideas such as the Biblical creation story must be false and certainly are so foolish we just can't even appear to give them any credit at all.
In general I've tried to stay away from placing value judgements on people because of their beliefs like saying someone is foolish. Sometimes insults can come across implicitly, just in context. It's definately not easy to keep from making discussions about fundabmental beliefs from becoming just an insult fest. Just the other day I was reading a Christian pro-life blog (I'm actually an anti-abortion atheist, a bit in the minority with secular people) and I was disapointed by how the pro-life writer was trading insults with pro-abortion individuals. I often am disapointed in alot of secular people when they resort to making fun of religious beliefs.
So back to theories. A theory is going to be an explanation of facts. You observe, make hypotheses and then you test them. Over years, decades, as the evidence and testing piles up, you can move on to a theory. This is why there is insistance. Behind that insistance is a long process with a foundation in observation, testing, and facts. In addition theories can be used to make predictions. For example, Einstein predicted in his Theory of General Relativity that light could be bent by gravity. 3 years later during a solar eclipse his theory was confirmed (different than proven).
It's true that Christians can't prove the story of creation in Genesis to be literally true.
Theories aren't really meant to be "proven". Theories are meant to be falsifiable.This just means that it is within the realm of possiblities to come up with evidence or observation that will prove false the explanation. So we have an explanation of facts and after a theory is formed testing and observation still continue. In that continued research it can be proved false at any time.
So with the story of creation in Genesis is there a way to prove it false? Is there some facts or observations someone could show or point to where you would genuinly say "oh, ok yeah that does disprove the creation explanation"? I ask this sincerely. I do believe that from the creation story we can infer things - make predictions. For example, if God created humans and animals as layed out in Genesis, the inference would lead us to a much different fossil record than is found.
We just don't know HOW God did it.
Ok. So knowing the how is important for me. Scientific explanations are about the how and this is where the confidence comes from. Less how, less confidence. More how, more confidence. And if the how is not know it should at least be desired/pursued. So relating this to creation, if we don't know the how, we should not have confidence in the explanation. I think it is at such an intersection where faith comes in.
But yet in your answer above you spent a lot of effort to discuss the semantics of words like "who" or "created", etc, but still you haven't any answer to the original question. And that's OK because just like the scriptural story of creation, science really doesn't have an answer. Only theories.
Semantics are everything when we delve into articular explanations/discussions. Meanings of words have to be clear. I did edit my post to answer the question in the way I think you are looking for: "no one created the earth". The next sentence you write kind of puzzles me as that's precisely what science does have. Answers. I don't understand this aversion to theories. Theories are powerful. They are not something that's "only". How is it that Enstein makes a prediction about powerful natural forces and that's exactly what they do? Is that an "only"?
But to go back to your comments about "core beliefs", how God created the heavens and the earth and created people isn't a core belief that affects salvation.
Ok. So that makes sense since there are Christians that accept the Theory of Evolution and even the Big Bang Theory and still are seen as Christians. They simply believe that these are just the "tools" of God.