Nothing we've ever observed shows there isn't possibility of that. It's a dumb thing to say either way. 

God is extremely powerful and exists independent of time and space.

The existence of a material universe with a distinct beginning demands a cause outside of the universe itself. A powerful creator God satisfies this demand (and certainly much better than the ridicilous ad-hoc multiverse theory).

Ahh can't have a debate about the universe and science without god being brought into the subject.

You're typing words here, that don't mean what you think they mean (powerful, indipendent of time and space, material, beginning, cause, outside the universe). And basically mean very little or are not precise enough for them to be useful in a debate about physics. But that's the whole point of religion, isn't it? It doesn't have to make very sense when you get down to the details, it just has to look good from afar and ring nice enough in our ears. It has to please.

I'm all for the arts, I just don't think that a nice impressionist painting of the river tells me more about how it truly is than most crappy photographs of crude schematics of its currents. It's something made up to make us feel on the inside, not to make us know the outside.

Let me cut to the point: you're proposing the god of gaps, that is getting smaller and smaller with our ignorance. But right now and in the foreseeable future we might not know much about the incredibly different and remote conditions near what we call the Big bang.

And yet, silly as that caged god might sound, it satisfies you. That's your call: you are free to see bogeymen in the shadows and fairies drawing rainbows as well.

For most logical people, though, an omnipotent being with volition and feelings and thought and moral that encompasses all conceivable universes and able to know the evolution of all that can come to be at all time is simply an infantile cop out. The laws of physics might sound more complicated to us - or at least to many of us - whereas saying somebody did it sounds simpler. But again, that's infantile thinking: that's relying on words ( person is a single word that implies incredible amounts of complexity ) instead of the underlying concepts.

In reality, where by reality I mean within the accepted bounduaries of logic, God is a more complex and ad-hoc explanation that multiverses, endlessly variating laws of physics, endlessly cycling universes. You're just sweeping the dirty complexity under the god-labeled rug and claiming the room of cosmology is now cleaner. It isn't.

This is not supposed to be about vague words, it's supposed to be about the numbers, precisely defined concepts, fasification. And math and physics taught us that there are concepts out there, from infinitesimal calculus to non euclidian geometries to imaginary numbers that sound weird and far from what we are trained and evolved to define (person), but in the end explain and reflect the world in elegant and wonderous ways. Zeno's paradox? that's just words. Trouble with infinite recession of causes? that's just words.

We're past that, or we should be.

nah man the universe was created last thursday didn't you hear?

As far as im concerned the universe was created the day I was born and will perish the day I die.

Referring to your the question of what caused the big bang or what came before it, the best possible answer we have right now is "don't know".

Though I did read somewhere about the possibility of there being some sort of indefinite cycle of big bangs and "big crunches". I have absolutely no idea how plausible that is though, or if I even remember it correctly.

All observed phenomena follow the principle of cause and effect. Nothing happens but that something preceeding it caused it to happen. If you are aware of anything to refute that basic axiom then please bring it to light.