I'll throw some sentences at those rhetorical questions. Existence is everywhere, there exists no where where there is no existence (I'm more of a language than math person, so you get a sentence crafted for form rather than function). As for what, the google tells me it's the state of having objective reality (prolbably not a definition you can stomach).
I think you misinterpret what I mean by existence, which I attribute to my own lack of language skills. I should have said "Where or what is all of existence.", if that makes any sense.
It's not that you have illogical beliefs that contradict empirical data that bothers me, it's that the way you try to express them, and your considering your word salad to be a syllogism that bothers me. It's like we're speaking different languages, and my rationality was born of
intellectualization, I don't know how to introduce it someone not used to rational thought, I'd be sputtering tautologies at best. I wish I could help give you the tools to develop more coherent theories, that would non-believers could criticize point-by-point while feeling that they might accomplish something by it, rather than become upset with the intractability of what is more word salad than syllogism.
I understand that much of what I say will likely never make any sense to somebody of a different mindset such as yourself. I'm sorry I cant articulate my logic in a manner that you can comprehend, not that you would ever attempt to in the first place.
Briefly however, if gravity, one of the four fundamental forces (say goodbye to that phrase if they come up with a GUT), is at least partly determined by sentient beings (who are abstractly unified into a god-like transpersonal being) believing in it, then creationism is necessary to explain the existence of the universe, since gravity working exactly how it does is necessary for the universe as we know it to exist (which means for us to exist as well).
Gravity is necessary for the universe as we know it in a scientific sense to exist, but who is to say the universe as we know it is how it has to be, or how it has always been? I believe in an malleable reality based on subconscious preconceptions, beliefs, and expectations, such as that of a dream. Is gravity necessary in a dream?
Your attempt to appropriate observation from quantum mechanics is errant beyond my ability to explain. It can take full time students focusing onn physics a couple years to gain a decent grasp of QM, those of us who have not expended similar efforts should not ever speak of abstruse scientific theories like that unless we're parroting the experts, otherwise we're bound to spout baloney.
I'm still not sure where I mentioned anything about quantum mechanics, and I have no idea how it relates to our discussion.
If this universe were a dream, I don't see why you'd assume the existence of discrete consciousness entities, would it not be more reasonable that they are creations of a single dreamer (basically God, an unmoved mover), rather than collectively dreaming up themselves, with all the paradoxes that entails? Furthermore, the success of our science and maths in modeling the natural world, and offering us predictive power,* would suggest that the creator set up a system governed by physical laws, rather than playing it by ear like the human subconscious does while dreaming.
Ive been trying to avoid the word to deter preconceptions, but God is essentially what I have been talking about. I don't believe in god as an actual entity with an agenda, but as a force of existence if that makes any sense. God to me is the collective. I don't deny its a paradox that we could dream ourselves up, but so is the idea of God if you look at it that way. Its the whole "If God created everything who created God?" conundrum, or in a language more science friendly "If the big bang created the universe, what created the big bang, and what created that, and so on..?" At some point there has to be something coming from nothing.
The success of our science and math proves there are physical laws in place, but it does not disprove the idea that those laws only exist because of our subconscious preconceptions and/or expectations.
*We hairless apes, evolved to be fruitful and multiply like every other animal, can use physical structures that allow our minds to create a utilitarian model of external objects/events based off of indirect information, in combination with a game of our own invention (i.e. mathmatics and logic..I will not get so philosophical as to discuss whether or not they are invented or substantive), and method for uniting the two to produce quantitative, reproducible, empirical data to determine how the world works, and to deduce whys that we can that we can then treat as hows after further experimentation. This knowledge being so accurate that we can apply it to escape the gravitational pull of the our planet, exchange information with someone thousands of miles instantaneously, replace our malfunctioning organs with those from somebody else, create automated assembly lines, shoot lasers at someone's eye and improve their vision, etc. etc. etc.
Or in my mind, we believe all that therefore it is, and conscious observation strengthens that belief. You see existence as being "set in stone" for lack of a better word, and believe that what you observe must undeniably be. I see existence as being malleable based on subconscious preconceptions, beliefs, and expectations of the collective (like a dream).
I don't expect to change your mind about any of this, at this point I'm just trying to articulate my view as best I can to perhaps nullify some of your attacks. Its not that I don't have or understand rational thought and logic, its that my logic does not align with your own.
I'm of the belief that one day my beliefs could possibly be proven (or disproven) via the scientific method, but it would require everyone involved to approach with literally zero subconscious expectations or preconceptions which seems a long way off before humanity masters that ability.
We can continue on if you wish, but at this point it has come down to somewhat of a religion vs science debate which we all know leads nowhere productive.
]..a spider fell unconscious on my keyboard as I wrote this.. 
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