Good grief, how about the latest prominent model and it's co-creator.
Vilenkins verdict: All the evidence we have says that the universe had a beginning.
Since Universe means everything (in a natural sense) exactly what existed before everything began to exist? I guess that everything only means some things as well as nothing meaning something these days. What's next?
Probably the most famous question in science is why is there anything instead of nothing. If there has always been something that has been quite a waste of time. Not to mention nothing natural has any reason to believe capable of being eternal or infinite even in theory. If there has always been something then time is infinite and since an infinite number of past events is not traversable there is no way to reach this on and now. Appealing to bounded infinites are no help because recurrence has been annihilated and time is not redundant.
Even Hawking agrees with my claims: To ask what happened before the beginning of the universe would become a meaningless question, because there is nothing south of the South Pole.
The Origin of the Universe - Stephen Hawking
That analogy only works if you comparing nothing to nothing.
As much as I cannot stand Krauss here is the title of his book: "A Universe from Nothing: Why There Is Something Rather than Nothing."
I am sure he spends the entire book explaining endowing nothing with properties the absence of being cannot posses but the title is enough.
I can prove that is the common model or predicted buy the models using only atheists and or non-theists if you wish. Both my sources above were non-theists. Every single video representation I have seen of the BB is of nothing that then is something that rapidly expands. You cannot even defend natural infinites or eternities theoretically.
You seem to suggest that while you cannot know anything about the universe origin you can be quite sure you know no deities were involved. Remarkable. Are not the person who claimed to have Jewish leanings?
Your equation is also meaningless. It should have been.
the probability of all non-natural possible creators - the probability of all natural creators of the universe equals 100%.
IOW
A supernatural explanation - a natural explanation = 100%
X - Y = 100% is the probability of X
X - 0 = 100%
The probability of a supernatural cause is 100%.