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Four Dimensional Big Bang?

  1. Apr 17, 2014 #1


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    Hello all, this is my first post here. I'm about as literate in physics as an ant is literate in algebra, but I was wondering if this theory about the big bang that popped into my head can stand on its own. (I'm doubt I'm the first person to ask this by any means, but I suppose it gives me a chance to introduce myself.)

    My theory is that if the big bang caused space itself to expand rather than just an expansion of matter from a central point within space (as I've come to understand), and if the universe "wraps around" on itself in such a way that you could go in one direction from one point and arrive at that same point again (as I've come to understand), that could potentially entail that whatever force that caused the universe to expand could be extradimensional.

    If we look at the universe as a four dimensional hypersphere, where the three dimensions that we know (length, depth and height) comprise the surface of that 4D sphere (much like how the surface of a balloon could be inferred as "two dimensional" in a sense,) perhaps some sort of "explosion" occurred in the fourth dimension, beneath our little three dimensional membrane wrapped around a hypersphere, causing space itself to expand?

    Of course we'd need an explanation for the origin of this little membrane, too.

    So how much of a fool am I making of myself?
  2. jcsd
  3. Apr 17, 2014 #2


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    There's no evidence for this. All we can say is, it's possible but unlikely.
  4. Apr 17, 2014 #3


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    As Bill K points out, your "understanding" that space is finite but bounded (the topology you described) is wrong in that it is possible but absolutely not established fact. Another possibility is that space is infinite (and always has been). Both topologies are mind-bending, but we're here so it must have been SOMETHING :smile:

    As for your hypothesis about hyperspace, that is also possible but possibly unprovable and as you say, it requires just as much explanation as what you are trying to use it to explain so it's still turtles all the way down.
  5. Apr 17, 2014 #4
    The others have covered your question and I have nothing to add to their comments.

    However this thread has numerous details covering what we do understand of expansion.


    its a fairly lengthy thread but there is some useful articles contained in it to understand the Cosmology view points from what we do understand.
    in particular the following

    http://arxiv.org/abs/1304.4446 :"What we have leaned from Observational Cosmology." -A handy write up on observational cosmology in accordance with the LambdaCDM model.

    http://arxiv.org/abs/astro-ph/0310808 :"Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe" Lineweaver and Davies

    here is an article covering expansion and redshift, written by myself with PF members assistance, tends to answer a lot of questions.
    https://www.physicsforums.com/showpos...6&postcount=10 [Broken]

    Phind's balloon analogy is also worth reading

    Another article I've written covering Universe Geometry is also useful

    those should catch you up to speed on cosmology basics in regards to geometry and expansion
    Last edited by a moderator: May 6, 2017
  6. Apr 17, 2014 #5


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    First, there was no central point. The big bang, or more accurately the expansion that occurs at the point in time right before our theories break down, occurs everywhere all at once, not at a single location within space.

    Also, saying "space itself" expanded is meaningless since all physical theories describe how objects behave within the underlying framework of spacetime. GR deals with the geometry of spacetime, but it does not deal with spacetime as an actual object that can move. In other words, galaxies are receding from each other not because space itself is moving, but because of the way the geometry of spacetime works.
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