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The wrong turn of string theory: our world is SUSY at low energies

  1. Mar 24, 2017 #221
    Following the previous post, I believe I really have identified the first genuine field-theoretic toy model of the sbootstrap - or at least, toy model of a crucial element of the sbootstrap. The field theory is just N=1 SQCD with Nc=2 and Nf=5. There is no electromagnetic charge, so this is not yet a model of the combinatorial aspect of the sbootstrap. But what it does give us, is a definite realization of the concept of "fermionic superpartners of pions and diquarks".

    It's because of the fact, pointed out by Shifman and Vainshtein, that for SU(2)c, diquarks, like pions, are goldstone bosons. So in the N=1 theory, they will have superpartners that are goldstinos, goldstone fermions. For SU(3)c, the nature of diquarks is less clear. But as S & V argue (pages 6 & 7): "As we pass to SU(3)color , the exact symmetry no longer holds, but an approximate similarity in the spatial structure of pions and diquarks is expected to hold". They propose a way to formally investigate this, by adding a triplet Higgs to SU(3)c QCD which breaks it to SU(2)c. A similar procedure should be possible for SU(3)c SQCD.

    It has been proposed before that the SM fermions are goldstinos. Here it seems we have to look for something a little more complicated - perhaps "almost-goldstinos" in the "magnetic theory" of a Seiberg duality.
     
  2. Apr 17, 2017 #222
    In a 1984 paper, "Split Light Composite Supermultiplets", one generation of leptons is obtained from SQCD with three colors and three flavors. Furthermore, the preons have quark-like hypercharges (see equations 3.15). The leptons are obtained at equation 3.42. Those "χ"s are components of the superfield T, defined in equation 3.18. If I am interpreting that correctly, T is a product of a quark and a squark.
     
  3. Apr 17, 2017 #223
    This was wrong, [itex]\Phi, \tilde \Phi[/itex] are chiral superfields in [itex]3, \bar 3[/itex] reps of SU(3) (see e.g. the start of section 3), so T is a meson superfield.
     
  4. Apr 17, 2017 #224

    ftr

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    Mitchell, why are you trying to figure out the proton, some people already got the noble prize for it, right.:sorry:
     
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