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Big bubbles - big bang

  1. Feb 16, 2014 #1
    Say I have two 5-dimensional bubbles moving towards one another in 5-dimensional space. When they touch, at the monent they touch, they meet at a 3-dimensional "point." As they join, the 4-dimensional hyperplane created their by common boundary immediately inflates from that point and expands.

    Is that about right ?
  2. jcsd
  3. Feb 16, 2014 #2


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    At first glance, just as two circles meet at an X,Y point (two-dimensional), and two spheres meet at a three-dimensional X,Y,Z point, it seems two 5-dimensional 'bubbles' or any 5-dimensional objects must require a 5-dimensional coordinate to specify a point of intersection.
  4. Feb 16, 2014 #3

    The notion of a point is more often an undefined entity in geometry, an axiomatic primitive that has no meaning beyond the intuitive. Any rigorous definition results in a circular arguments.

    While a point may be designated with any number of dimensions depending on the space, it alway has a magnitude of zero in every direction. A point on a line and a point on a plane could be seen as equivalent objects.

    Back to bubbles. The four diminsenional space arises from the "point." An observer in the 4-D hyperplane at some later time would remark; "the universe spontaneously arose from nothingness."
    Last edited: Feb 16, 2014
  5. Feb 17, 2014 #4


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    A point has no dimensions.

    The way you stated this question was too vague for me to answer what the dimensionality of the intersection would be. However, how two such bubbles interact when they meet depends entirely upon the physics of whatever they are made of.
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