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I Are the sphaleron & superstring just the epicycles of our era?

  1. Jan 28, 2018 #1
    Are the sphaleron & superstring just the epicycles of our era?

    I just learned of this thing called a sphaleron, which from my primitive background in physics (i.e., physics for engineers and some self-study of modern physics) just strikes me as "we see stuff that doesn't fit out model & symmetries, so we just invented this thing so that the equations balance out" - like Neo from The Matrix. And superstring theory strikes me as "if invent more dimensions (i.e., add more arbitrary values for coordinates in the dimensions", we can make our observations make sense.

    This just sounds to me like the pre-Copernicus astronomers fine-tuning their celestial sphere to keep up with more accurate observations.
  2. jcsd
  3. Jan 29, 2018 #2


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    Your two examples are wildly different.

    A sphaleron is a mathematical possibility for an interaction in quantum mechanics that doesn't have a Feynman diagram to go with it. It is part of the Standard Model and should only manifest at high energies. Other parts of the Standard Model (like the Higgs boson) took many decades to appear and showed up roughly at the energy scale where it was expected to appear. Certainly, it is not an epicycle. It was a one time implication of an existing theory that has worked very well and was neither invented or has it been changed, to address any problem in physics.

    String theory is a logical framework if you start from the first principles of core theory in physics, but connecting it to the observable universe has proven more difficult than anticipated. It also is not an epicycle as it isn't being used to make current or past theories produce accurate predictions.

    One could look at supersymmetry theory as an epicycle because this is an area where it is constantly being returned to fit new discoveries, when supersymmetric phenomena that are suppose to be "just around the corner" fail to be detected.
  4. Jan 30, 2018 #3


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    String theory, by itself, is not an epicycle. However, to make string theory consistent with observations requires a complicated extra work which might be interpreted as modern epicycles. The original idea of string theory was to replace the standard model of elementary particles+gravity with something simpler, but the resulting stringy picture of the world turned out to be much more complicated than the standard model. So complicated that, at the moment, nobody really understands it.
  5. Jan 30, 2018 #4
    Swampwiz.. have you read sabine blog about string theory? http://backreaction.blogspot.com/2018/01/sometimes-i-believe-in-string-theory.html

    I just read it today and it's the same funny rant... she started:

    "They talk about me.

    And I can’t blame them. Because nothing else is happening on this planet. There’s just me and my attempt to convince physicists that beauty isn’t truth."
    (and she ended with)

    "But science isn’t about belief, it’s about facts, so here are the facts: This trust in beauty as a guide, it’s not working. There’s no evidence for grand unification. There’s no evidence for supersymmetry, no evidence for axions, no evidence for moduli, for WIMPs, or for dozens of other particles that were invented to prettify theories which work just fine without them. After decades of search, there’s no evidence for any of these."

    Well my comment about string theory (and your message) is... what if string theory is like the situation where the Dirac Equation was being thrown into the hands of the period when they didn't believe in atoms but matter being continuous.. they missed key insight that would make the Dirac equation makes sense.

    This is connected to Sabine rant about beauty not there in the equations.. consider the following analogy.

    Let's say there are beautiful women in the beach.. is there beauty in the constitution and equations where they are made of.. if you will use the arguments that Earth, Wind, Fire, Water can't produce combination that can produce them hence Earth, Wind, Fire, Water is not beauty and nature is not beautiful.. and ignoring the fact those women exist.. then it's a logical error. We are in similar situation. We ignore so much of nature that we only find the physical world as existing.. and then make rant how there is no evidence for grand unification when we may be ignoring the 5th and 6th fundamental force or sorta..

    The solution is to wait for another century when science would investigate deeper. Also we are now in Catch-22 situation. Physicists investigate only a small region of reality.. and they complain the equations don't match them.. of course.. because the complete equations describe a larger reality.. they are like looking at a glass darkly...

    Another example. They say there is no single theory that can describe dark matter in the universe because there is different conflicting observations for every case. Yet when you tell them to investigate what if there is no single theory that can describe dark matter because maybe part of dark matter is sentient and dynamic.. they will say.. no, our current theory doesn't support it... then go back to ranting how there are no WIMPS, etc so what are dark matter really and then repeating there are no beauties in the equation and reality is maybe because we win a one of billion of billion in jackpot.... ala Sabine rant. This is another Catch-22 situation. We are really in a mess.

    Our solution is to wait for the current generation of physicists to dwindle and for the next generation of physicists to be born who can see more and has more insight and willing to do unconventional experiments outside the box. Then our world and scientific knowledge will evolve by leaps and bounds.
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