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How Would I Visualize the Extra Dimensions of String Theory?

  1. May 10, 2010 #1
    Greetings. My question comes in two parts.

    Part one - In most "low-level - made for t.v." explanations of the extra dimensional space they describe these extra dimensions as "curled-up". If I were to visualize the extra dimensions of string theory would it be better to think of these extra dimensions as having their "end points" connected to the endpoints of our visible 3 linear dimensions (Lets just say there is endpoints for sake of discussion) yet their "length" in comparison to the 3(X,Y,Z) is very,very small. My other idea for visualization would be something like a infinite spiral such as that of a Mandelbrot set.

    Part two - Are these dimensions spatial like our 3(X,Y,Z) or more 'exotic' like space/time in the String Theory models? Or do some groups of thought consider them a sort of 'placeholder' to keep the Theory 'stable'?

    -Thanks in Advance
  2. jcsd
  3. May 10, 2010 #2
    As for the dimensions, humans are pretty much condemned to be completely unable to picture them. I'd go by thinking of a sheet of paper as the universe. It's extent in two dimensions is rather large, compared to the thickness (3rd dimension). If we now were 2D beings living in the surface of that sheet, we wouldn't notice (or be able to picture) the slight thickness, but we'd recognize the extent of the other two.
    Now do that with a 10D sheet, and you're almost there ;)

    The nature of these dimensions seems to be subject to ongoing discussion. One time-like dimension seems mandatory, the rest is spacial. But if I recall correctly, there also is the idea of a second time-like one, but it might be that my memory is playing tricks on me here.
  4. May 11, 2010 #3


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    People have thought about it, but as far as I know, there's never been any significant success in making a theory with more than one timelike dimension.

    And personally, I'd think of the curled-up dimensions more like the one that wraps around the surface of a strand of spaghetti. They're generally considered to be periodic, rather than having "ends".
  5. May 12, 2010 #4
    Tangent thought: Technically that would be 3D beings that are very thin. :smile:Perhaps that would make a good metaphor for us 3D beings stuck in 4D(space/time) existence. Back to the topic...

    Diazona - calling these dimensions periodic rather than having ends, could you elaborate a bit for me please if you could. Would I think of these as the other three dimensions (X,Y,Z) -no one is certain if they are finite or not? Are these 'curled up' dimensions smaller than the Planck length?
  6. May 15, 2010 #5
    Well, mabe if we had a few more eyes? :rofl:

    Well, obviously (In case of sTheory) these "extra dimensions" exist all around us... we are too "big" too see them..

    If we did, could our eyes even adjust? I am thinking they would..

    It would be something like seeing a new color~
  7. May 15, 2010 #6

    but see, we can't see new colors.. our eyes only have receptors for the colors we can see.

    I don't think we could ever see a higher dimention, not in our current state that is.
  8. May 15, 2010 #7
    Yea, it would make more sense. I agree, thnxx))))
  9. May 16, 2010 #8
    I was well aware of that being thin is different from being short one dimension. Of course, such beings need to be purely hypothetical, as they at least couldn't be made of any known form of matter.

    The thought of perceiving higher dimensions is an interesting, too! Imagine, again, being such an (actual!) 2D entity, with 2D eyes that can only see 2D (1D+parallax 2nd like we do with depth). What would such a creature see if it was lifted off it's 2D plane, and tilted into it's direction? It would see slices of the "inside" of it's world, which has to be one hell of a grotesque sight I might add. Would be interesting to see how that would look like for our world looked upon from a 4th dimension. Has anyone ever tried to visualize this? I mean in actual pictures?
  10. May 19, 2010 #9
    More Tangent thoughts - Perhaps we are 4-dimensional beings with the 4D being very thin (at least to our perspective) - We always exist in the present point in time in our observation, the very thin slice of 4D. Like the flatland beings and their thin 3D slice. In Flatland (see Issac Asimov - Cosmos - for anyone that has not read) For them to have a 3rd dimension projected equally at all points flatland would have to be on a surface of a sphere. Could we be on a 3D sphere in a 4th dimension?
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