So I was on the shitter about half an hour ago (you're welcome for that information btw, for those who were about to thank me) and I was just thinking. I once subscribed to the concept that there is a possibility that there are many many universes (practically infinite) with practically infinite possibilities (if you subscribe to the multiverse concept), in which different decisions were made or different planets collided or whatever. But it got me thinking:
Why should those different things happen? The only case in which it would happen is if the universe started with different fundamental forces, or a different amount of energy or whatever, or had different mass or something (Even slightly). Other than that there is no different for anything to be different. Now I don't like being a downer or one of those people that say freewill doesn't exist, but we're looking at ourselves from a biological standpoint. If you look at us from a physical standpoint, there is no reason for any individual action to be different. Let's imagine it like the asteroid that destroyed the dinosaurs, you could say imagine a universe where it's not there. But if it started exactly under the same circumstances that we did, why would it not? The exact same planets and asteroids would form, same planets would form, and other asteroids would bump into other asteroids to get that asteroid to reach and hit Earth. Anything short of it would be magic.
So if we look at ourselves from a physical standpoint, it's highly unlikely that (on the human level at least) anything would be different in other universes. If those universes started out even slightly differently, they would be completely different. Imagine there was slightly more energy in one universe, perhaps Earth would never exist, but it could only happen in that sort of way. In my opinion, unless an EXTREMELY advanced society perfectly plans out and calculates every single thing for something to happen but slightly changed (Again this would be massive, unlikely, and unnecessary) to such a perfect degree that (for example) you did take that job interview and became rich or something. So in my opinion it's near certainty that there is only one of you in existence. This is only assuming a natural universe in a multiverse of course (this is something that I don't believe in but I find to be very possible and very logical, assuming it's a natural universe). And also that whatever happened at the beginning, guarantees a certain outcome and each point. That even our thoughts, if in the realm of physics (which again, they are, if you subscribe to the idea of a natural universe), are set in stone and those future actions will happen.
We make the choices, yes, but those choices cannot be different, just as an asteroid that wiped out the dinosaurs must happen if a universe starts under exactly the same conditions as us. So free will in my opinion isn't necessarily an illusion, simply that whatever happened 4.7 billion years ago sets forth the same thing. Similar to how in physics if you repeat the same thing (in theory) under the exact same conditions, you should receive the exact same results. Logic (in my view) dictates that it works across universes if those same laws and starting conditions are exactly the same. I don't know if I'm explaining it right, feel free to correct me on any points or to ask questions cause I'm not sure that I wrote this completely coherently/correctly lol.
simulated universe is sorta like the idea the universe is a dream or matrix .umm the free will change wont be answered until quantum is understood. thats what is so weird about it. you seem to understand classic physics. under classic it would be deterministic universe. quantum really throws that off. everything becomes a possibility (random psuedo freewill). time really throws it even more off. its hard to explain or understand. try to learn what the hell quantum spin is and you might see how hard it is
So we're basically in one big game of Spore? Lol
Well I believe in a simulated universe (As you know) and in a simulated universe a multiverse is definitely possible (Basically different save files lol) but if we assume the entities/computers that generate these universes do not interfere it's impossible for minor differences, only completely major ones, and to me I view science as a logical explanation that I would believe to be true in a natural universe and explain the laws (At least in physics) only in a simulated universe. I don't even know what I'm saying lol. But to assume that we're the only universe in existence would be extremely unlikely considering the sheer perfection of the laws of physics that allow for complex life to exist. My theory on the origin of existence in general is that in the very very beginning there was a universe with crazy ass or non existant laws, where nothing existed, then in a universe where anything can pop into existence, it popped into existence (hard to explain lol) eventually that universe started spawning other more stable universes, eventually intelligent life was able to form and created our simulation, or even the simulators that are simulating this universe are simulated but somewhere down the line there's a "real" universe.
That's actually a really neat way to put it. I from time to time think "in another universe, I got that job I interviewed for and I'm living happily" but the reality is that thoughts like those don't really serve a purpose. Thinking another version of me succeeded despite still being me in every way shape and form makes no sense, and even if it did, what use is it to consider it? If there is another me living happily with a good job, then good for her I guess. It doesn't change what's happening to me now.
To think of it this way is much more motivational; no, there's only me, only I can make a success of myself. There's not some other carbon copy of me who got everything she wanted just because she was born in a different dimension.
In my opinion, the multiverse theory only serves a purpose in entertainment and or the possibility of interdimensional travel (which in itself would only be useful if multiple dimensions were proven)