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What is the membrane theory?

  1. May 11, 2010 #1
    What is the membrane theory?
     
  2. jcsd
  3. May 11, 2010 #2

    bapowell

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    There is nothing named specifically as such. Could you give us a context within which you think this theory applies?
     
  4. May 11, 2010 #3
    I believe he'a referring to Brane Cosmology?
     
  5. May 12, 2010 #4
    No, membrane theory is correct. Sometime its referred to as M theory. Its a theory that took off from string theory, it says that instead of 10 dimensions, theres 11. And in the 11th dimension, the hyperspace containing all the other dimensions, our universe is a floating membrane. It could be a donut shape, or any shape. But theres numerous universe membranes floating around in this 11th dimension. Some are colliding, which in a part of this theory could be an explanation to the big bang. Its basically a different version of string theory because it still has little oscillating strings at the microscopic level, but it introduces that theres an 11th dimension and that universes are giant membranes or bubbles floating in a hyperspace in an ocean of bubbles. So not only are there billion of stars in a galaxy, and billions of galaxys in a universe, there are also billions, maybe more of universes.
     
  6. May 12, 2010 #5

    bapowell

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    You've just gone a bit fast and loose with your take on M-theory. First off, M-theory may or may not stand for membrane theory (it's one of those dumb things that only Ed Witten knows). The original formulation of M-theory does indeed involve two branes at the orbifold fixed points of an 11th compactified dimension. Not sure why you're bringing up donut shaped universes -- the topology of the universe is not germane to the discussion of M-theory. There may not be multiple branes. They might not be colliding. You speak as if these are predictions of the theory -- they are not. M-theory, by itself, does not claim that there are infinite number of universes. In any string theory, this is of course possible but by no means necessary. M-theory is not a 'different version' of string theory. The theory itself (it's conceptual underpinnings and defining principles) are not known -- it is believed that 11-dimensional supergravity is the low energy limit of M-theory. But that's really all we know about it. It should be thought of as the unifying theory of the 10-dimensional string theories -- in the weak coupling limit M-theory reduces to these 10D string theories, which are themselves interrelated through an interesting web of so-called dualities.
     
  7. May 12, 2010 #6
    Watch the show parrallel universes and heres a clip from it:



    There are others that explain my point if you keep looking
    And in here it explains that m theory is an extension of string theory, wikipedia is a great source for things like these:

    http://en.wikipedia.org/wiki/M-theory
     
    Last edited by a moderator: Sep 25, 2014
  8. May 12, 2010 #7

    bapowell

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    Please read my post carefully. I stated that M-theory is a unifying theory of the 10D string theories -- it is very much an extension. My point in responding to you was merely to tone down what you said -- you made many claims, some of which may well be true, but M-theory doesn't need to predict multiple parallel universes even if it can accommodate them. It's important to be careful about what theories predict and what they don't, especially now that we are doing real experiments that shed some light on these things. Also, thanks for the link to M-theory on wikipedia, and thanks for assuming that I don't know what I'm talking about. But I'll keep 'looking'...

    EDIT: Also, the link you provided is speculation. The colliding brane theory, the so-called ekpyrotic universe, is indeed based on M-theory. But the big bang did not necessarily happen that way. But M-theory could still be correct. This is my whole point -- M-theory can accommodate such an event, but it is by no mean compulsory. M-theory is therefore not defined by these speculative events -- instead, these events are possible features of the theory. Be careful separating real, factual cosmology with speculative theories.
     
    Last edited: May 12, 2010
  9. May 14, 2010 #8
    Yea sorry i got a little over excited, thank you though now i know in the future i should be not only researching things better but separating them from fact and theory.
     
  10. May 19, 2010 #9


    yes, this.

    I feel far too many people connect something being mathematically possible, to being mathematically proven.
     
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