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I Is string theory dead or still valid

  1. May 27, 2018 #41

    phyzguy

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    Can you give an example of a known fact that is derivable from string theory and explain how it is derived from the set of string theory assumptions?
     
  2. May 28, 2018 #42

    FactChecker

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    I have no expertise on this subject, so I can not. My question / comment is a general one that keeps occuring to me when the issue comes up. I just assumed that there were some constraints on the theory. If there are no constraints at all, either to fit facts already known or to predict results, then I don't know what the purpose of the theory is. It never occured to me, till you asked, that the theory may not fit any already known facts.
     
  3. May 28, 2018 #43

    phyzguy

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    You are the third person in this thread who has made the claim that string theory makes testable predictions, and the third person who has been unable to name one when I challenged them. I think, as I said in post #32, that string theory is not a "theory" in the sense that we usually mean. It is more a set of ideas that might some day be concise enough to allow predictions to be made.
     
  4. May 28, 2018 #44

    FactChecker

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    an
    Sorry if I wasn't clear. Let me clarify my earlier post. Are you saying not only that it can not make predictions of new things to be verified, but also that it does not fit and support any already tested facts? That would be a strong statement that you are making and it leaves the obvious question: What motivated the theory if it can't explain anything we already know and can't predict anything new. The difference between the two cases is only the chronology of the facts being verified versus the development of the theory.
     
    Last edited: May 28, 2018
  5. May 28, 2018 #45
    It looks pretty?

    Cheers
     
  6. May 28, 2018 #46

    phinds

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    The early developers thought it eventually WOULD make testable predictions. Even after forty years of none such some of them apparently have still not changed their minds.
     
    Last edited: May 29, 2018
  7. May 28, 2018 #47
  8. May 28, 2018 #48
    String theories have not been shown to be either true or false.
    A lot of things are like that.
     
  9. May 29, 2018 #49

    MathematicalPhysicist

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    So they are metaphysics theories.
     
  10. May 29, 2018 #50
    That would seem to be one very big attraction. Despite the complex maths vs Occam’s razor, ST would seem to have some very elegant mathematics behind it.

    String theorists are betting that it is a big, huge, comprehensive and immensely complex version of Dirac’s equation out of which anti-matter miraculously ‘plopped’ out, that its elegant maths predict boatloads of unsuspecting physics...that its mathematics are an Oracle...


    IH
     
    Last edited: May 29, 2018
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