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Need some clarificationregarding GRAND UNIFIED THEORY

  1. Mar 26, 2006 #1
    (If this thread doesn't belong to this group, Iam sorry"...
    Regarding the "GRAND UNIFIED THEORY"
    It is the theory to find a link between the "four fundamental forces of nature"....and suppose that somebody some day find a "link"...then can You tell me what he has really found "what one can predict from the "link"...
    Does Nature permitts anybody to Find that link....
    THERE ARE IN THIS NATURE MANY "WHY" Questions to be answered...

    >> Why there is LOW ENTROPY IN THE PAST


    Does these questions when answered are not "grand unified theory"

    Pls look at this...

  2. jcsd
  3. Mar 26, 2006 #2


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    The term "grand unifying theory" (or better: theories) is first of all not so "grand" and has a rather precise meaning: it is meant to be a unifying theory of the strong and the electroweak interaction, which, in the standard model, have their "independent" life one next to the other. It doesn't really address the issues you raise at all.
    After the success of the unification of the weak and the electromagnetic interaction into the electroweak interaction, people went on a chase to incorporate the strong interaction too. Many schemes have been proposed ; I think the first one was the most "obvious" one: electromagnetism had the gauge group U(1) ; the electroweak interaction had the group SU(2) ; the strong interaction all by itself had the group SU(3), and it turns out that SU(5) contained each of these subgroups. So SU(5) was proposed as a first grand unifying theory. But the problem was that it predicted the decay of the proton at a much faster rate than has been experimentally observed afterwards, so it went down the drain. Then people invented lots of other schemes. There is no generally accepted grand unifying theory - as far as I know - at the moment.
  4. Nov 21, 2008 #3
    A unified theory would have to incorporate the strong and weak forces, yes.
    It would have to be a theory that is transposable at all scales. A fundermental pattern of creation.

    Instead perhaps of looking for a particle that is the building block for everything and therefore is the foundation stone, if you like, of reality, why not look for a fundermental pattern of dynamics of spacetime?

    A unified field theory would have to assume that everything is in fact one, otherwise you can't have unity. It would be a transposable pattern or set of equations that can be octaved up and down in scales of resolution. Thus being both expansive and contractive.
  5. Nov 21, 2008 #4
    hi i'm new here.

    personally i find the whole GUT fascinating.

    which theories do you guys find compelling as GUT candidate? anything that might meet the GUT expectations...anything beside string theory. i don't necessarily think string theory is at all neat as GUT should but that's just my gut feeling speaking.
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