“The broadest definition of the universe can be found in De divisione naturae by the medieval philosopher and theologian Johannes Scotus Eriugena, who defined it as simply everything: everything that is created and everything that is not created.” (Wikipedia (for what it's worth)).
Consider that there turned out to be more to the Universe than there was thought to be. What was considered to be the Universe turns out to be one of the Multi-verses within the Universe.
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If the “Uni” in Universe derives from the Latin for One, the word “Universes” is kind of contradictory.
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“IF the multi-verse theory were correct then GOD would HAVE to exist simply because ‘Scientists’ say ALL things MUST take place in ‘Infinite Universes’!”
What I've read that they've said is (more or less) that in order for God to be God everything that could happen has to happen. (I may not have quoted that accurately.)
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“Wouldn't it make sense that if GOD were to exist in even one of these universes then NONE of the rest of those universes could or would exist!?”
No. First, given what I wrote above, those universes aren't really universes, but multi-verses within the universe. I don't see why he can't exist in all the multi-verses within the universe. (I know that's not the way “they” talk about it, but sometimes you have to kind of translate in your own head what people say in order to make sense of them.)
Second, what you wrote can be read to imply that God is dependent on a universe to exist. I don't see that. He exists independently but within the Universe (including its Multi-verses) He created.
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“HOW could such a chaotic universe or in this case Chaotic Universes exist!?”
Granted, you and I are unable to make sense of it, but doesn't mean it's Chaotic. The problem more likely rests with our lack of ability.
http://www.sciencenews.org/view/download/id/66526/name/CIRCULAR_REASONING_ ~ this is a shot of the fundamental heat patterns at the limit of resolution at the very edge of the Universe. It’s pretty obviously one of a number of scientific flask brackets ~ so...................