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Nonexistence outside the universe

  1. Dec 23, 2011 #1
    Hello, I've just discovered these forums within the last hour or so. I am rather intrigued and I hope to learn something in making myself familiar with the concepts and theories that fly around here. However the reason I've stumbled across these forums is because I need a question answered. I'm not sure if this is the correct section to post it in, so if it's not then please redirect me.

    Earlier just watching television, an idea planted itself in my head and it's continuously grown. It's a fictional idea of a man who somehow escapes the confines of the universe (accidently of course) into absolute nothingness. Somehow (unknown how to him) he gains consciousness in this nothingness and realizes that he can create and destroy matter and energy. I haven't really thought of the progression, but eventually the "creator" creates a world with similar physics to the universe (which he can only break of course). The world created will be a utopian society based around appreciation for science and classical education, but the creator becomes depressed and wants to go back to the universe. However after many years in his self-made universe he gives up. Eventually after a few generations, a curious creation will come to him and ask him how he became a god. The creator will explain his story and the creation will spark new enthusiasm for getting back to the universe which they eventually do.

    It's a basic of shell of the story I wish to tell, but to get started, I need some basic knowledge about physics in the universe. I'm not sure but from what I understand, there is nothing outside the universe correct? I don't really understand though, what does the universe exactly expand into? If there is something "outside" of the universe, is there a name for it? I understand my story couldn't possibly happen but I think it really has the potential to evolve into a very unique work of fiction. Any help in these few questions is appreciated, and would the story be anything you personally would have any interest in? I plan to call it "A Man Called God"
     
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  3. Dec 23, 2011 #2
    Not sure if this is really the answer to your question. The theory i've heard of is that once you reach the supposed "edge" of the universe, it wraps around, like pacman, so the universe can be thought of as a sort of beach ball (although the universe is mathematically proven to be flat.) Where you can keep circling around and around it. If you're just beginning to learn Physics, I would suggest getting Brian Greenes "Fabric of the Cosmos." I understood it almost completely, and I'm only in 9th grade.

    Also, the universe expands faster than the speed of light, so it would be impossible to get to the edge.
     
  4. Dec 23, 2011 #3
    That's quite interesting, like a flat disk you mean? It really wasn't what I was looking for though. My question wasn't about if you could escape the universe, but rather if it's even possible to exist outside of it (if there even is an outside).
     
  5. Dec 23, 2011 #4

    Nabeshin

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    The word 'universe' as it is conventionally used, is typically taken to mean everything. That is, it is impossible to exist outside of it, for if you were existing in some place, that place is by definition part of the universe. Now, there are more nuanced definitions of the word. For example, if we consider the whole blob of everything the 'universe', separate regions are causally disconnected, that is, light hasn't and (cannot) propagate between them -- what happens is one is completely separate from what happens in another. These are another definition of 'universe', and with regard to the particular bubble around ourselves, we call it the 'observable universe'. Surely it would be possible (if you could somehow invent a way to travel faster than the speed of light, wormholes or the like) to go outside of the observable universe, but you'd likely be disappointed and find it is almost exactly the same.

    Willis666: This is a question of the geometry of the universe. The scenario you describe is when a universe has positive curvature -- that is, it curves in on itself like the beach ball you mention. In this way, the universe has a finite area, but yet is unbounded (has no edges). It's certainly a popular conception of our universe, since it doesn't require us to explain edges or result to saying things are infinite. It is NOT mathematically proven that our universe is flat, however. We have MEASURED that the curvature of our universe is very CLOSE to zero. If positive curvature means a beach ball, zero curvature is exactly what you would imagine -- a sheet of paper. Conventionally, we imagine the sheet extends out to infinity. So this is the model best supported right now. However, I should note, that the universe can still be positively curved, but the radius of curvature must be very very big (bigger than the size of our observable universe!) for us not to have noticed it. Similar to how if you live and work around New York City, you'd never think the Earth was curved because of how much larger it is than what you're used to. The situation can be analogous for the universe as a whole, the only way to nail it down more is more precise measurements.

    That's a little background, but to get back to your original question, the scenario you're thinking about (while making for interesting science fiction) is completely ludicrous from a scientific point of view. The universe does not need anything to expand 'into', so there is no need for what I'm sure you're imagining is a man outside looking 'in' to the universe. There are countless threads about this on PF, and I don't really care to explain again, perhaps someone who remembers a good one can link it here.
     
  6. Dec 23, 2011 #5
    Thanks for the answer, but I still have questions. Is there any "space" between these regions? Or is there a nothingness where physics don't apply? If I were to place my character into one of these regions that imploded upon itself (if that's even possible) would that region have ceased to exist or would it be a random mess of particles?
     
  7. Dec 25, 2011 #6

    Drakkith

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    Any regions that are disconnected from each other are only disconnected in the sense that if something happens in one area, the information, since it is restricted to travelling at light speed, c, has not had time to reach the other area. This information could be the light from an exploding star, a very powerful radio transmission, or anything really. The point is that these things have to travel across space to reach different areas. There is still space between them, they are simply too far away for any light to have ever reached each other.

    Now, I wouldn't let this destroy your creativity or your imagined story here, but I would simply modify it a bit. Perhaps your character has been transported to a parallel universe where the rules are a bit different and he is in fact able to manipulate energy and mass and all that. Hell, you could just ignore the laws of physics here in your story if you wanted to anyways. Perhaps the man is "granted" these powers by another unseen divine being. Or however you want to put it. Any way you do it, the premise of your story is at it's core one that goes against our current knowledge of how the universe works. Since that is the case, I say do what you want. You can make it as real or as not real as you want.
     
  8. Dec 25, 2011 #7

    I think that your basic plot, by itself, makes it impossible to stick with physical reality. That is not a bad thing, there are many works in literature and art made in that manner. Drakkith gave you good advice, focus on whatever you are trying to tell, not on physics.


    Hell yeah! My wife's cooking.
     
  9. Dec 25, 2011 #8

    Dotini

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    If the universe is expanding, but does not need anything to expand into, doesn't this mean that there is either nothing beyond the universe, or that the universe is expanding into something?

    Respectfully,
    Steve
     
    Last edited: Dec 25, 2011
  10. Dec 25, 2011 #9

    Nabeshin

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    It means neither of these things, although as I hinted at above, it is incredibly ambiguous what is even meant by 'beyond the universe.' Here's the analogy I like to give... Imagine if I just have a flat plane, an infinitely large sheet of paper. Now on this paper, I place dots every centimeter, so they line up in a grid. The pattern continues infinitely in every direction ( http://www.mathcats.com/crafts/craftimages/dotsgridmini.gif , but infinitely large). Now, all I do is I stretch the infinitely large sheet so that the distance between adjacent points is now 2cm, instead of 1cm. The universe has expanded! This is the kind of expansion we see in our own universe, since the velocity of recession of any dot will be proportional to its distance away.

    Now, in the above description, I have never needed to reference anything outside of the infinite plane -- indeed, that's all there is. Furthermore, the plane is not expanding 'into' anything at all, it was infinite to begin with! To extend this situation to a spherical geometry, you just have to imagine that the dots are part of the surface of a sphere. To a creature confined to live on the surface, the situation would appear similar to the flat plane case just described. And again, with the expansion, the distance between dots simply increases, without reference to any exterior thing. (A side note here, if you're picturing this, you're probably imagining a 3D sphere, and then thinking about its 2D surface. This is where the intuition that it must expand 'into' something comes from. But this is merely a human limitation, the 2D surface of the sphere does not need to be embedded in 3D space, it only needs to be for us humans to visualize it! The fact is, it is completely described by itself, and needs no reference to an outside space).

    Again, we can say nothing about a 'beyond' the surface of the sphere. I hope this clarifies some, or perhaps I've just confused the issue!
     
  11. Dec 26, 2011 #10

    Chronos

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    The boundary of the observable universe is the big bang. So, its the same as asking what existed before the beginning of time. That is unknown, and probably unknowable, IMO.
     
  12. Dec 27, 2011 #11
    Well if we're talking about a supposed place beyond the universe then surely it wouldn't have any space-time coordinates and I don't think we even have any name for it, conversely prior to plank's time same thing occurs.
     
  13. Dec 27, 2011 #12

    Drakkith

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    I think it really depends on what you mean by "Universe". According to mainstream science, the Universe is the totality of everything that exists. You cannot be "outside" of the universe. It's simply not possible.

    However, this is not the only way to define Universe and the personal view on what the Universe is defined as can vary significantly depending on the context and person. Even science has it's differences, such as Multiverses.
     
  14. Dec 27, 2011 #13
    Steve, consider the following question : what is south of the South Pole ? It is immediately clear that this question does not make sense. Why ? Because the grid which defines the pole is closed in itself. There is no "south" from the pole. Likewise the universe - what is outside the universe ? This does not make any sense, because there is no "inside" and "outside". The universe is just simply everything there is, just like the earth's surface is all there is for the coordinate grid laid onto it. The confusion arises because us humans aren't able to visualize a manifold in more than three dimensions which isn't embedded in "something" else.
     
  15. Dec 27, 2011 #14

    Dotini

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    Thank you, Markus. This explanation works well for me!

    Respectfully,
    Steve
     
  16. Dec 27, 2011 #15
    Thanks for the replies here. I know the story is completely unrealistic, I was just trying to gain somewhat of a basic knowledge of where to put my character. I guess I'll put him in a parallel universe then.
     
  17. Dec 30, 2011 #16
    Hello,

    Just some advice. Try not to worry too much about the mechanism for your main characters "elevation to godhood" as most ideas will be scientifically impossible given our current understanding.

    For a novel to have any long lasting impression (especially sci fi) requires a profound ending/overall message.

    Just wanted to give you advise as an enthusiastic sci fi reader.
     
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