Is there some no-go theorem for $D=9$ Kaluza Klein QCD+EM? While QCD is a typical product of AdS/CFT and some other research trends in extra dimensions, I have never found in the literature an example producing the non-chiral part of the standard model, colour plus electromagnetism, or even color alone, from D=9 Kaluza Klein.
In principle such theory could be obtained


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*by compactification on the 5-sphere $S^5$ and adding some Higgs to break $SO(6)$, or

*by compactification on the product manifold $CP^2 \times S^1$, producing directly the gauge group $SU(3) \times U(1)$.
Besides, QCD alone could be got from a $D=8$ theory on $CP^2$.
The traditional argument about the absence of chiral fermions do not apply here as both QCD and EM are defined with Dirac fermions. So if there is a non-go theorem at work, forbidding the scheme, must be a different one. Here the question: Is there one? Or, as a counter-proof of my question, is the example actually done in the literature and it only happens that I have not searched deep enough?
 A: While it is certainly possible to get an $SU(3) \times U(1)$ gauge group from the metric alone, if one started with a 9d theory, there are several issues with using Graviphotons as gauge bosons in a 4d theory.
Most prominently, in addition to vector bosons you will always create scalars in the adjoint from internal components of the metric, which we do not observe.
Furthermore, while the effective gauge group active at everyday energies is indeed a vector-like $SU(3)_\mathrm{c} \times U(1)_\mathrm{em}$, we do know for certain that there are effects that are due to a chiral $SU(2)_L \times U(1)_Y$ which is broken to $U(1)_\mathrm{em}$ via the Higgs mechanism. I'm not aware of someone reproducing spontaneous symmetry breaking on off-diagonal blocks of a metric (I think Witten tried some time in the 80s, but I don't have there reference at hand right now).
A: With an answer selected (and bounty awarded) it is time to open a community wiki for explicit references on work along the line of getting QCD + EM, or alternatively QCD alone or QCD + "4th colour" extracting the group from the extra dimensions.


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*An early 1975 work of founding fathers of string theory claims to have a O(6) and then a SU(4) group from the compactification of the usual six extra dimensions, but it does not use it for colour but, as will be traditional in the future, for generations. It is "Dual Field Theory of Quarks and Gluons" by J Scherk and John H. Schwarz. But it mentions an even earlier, 1965, work by Y. Neumann also pivoting on six extra dimensions and SU(4):  http://www.sciencedirect.com/science/article/pii/0031916365902258 http://inspirehep.net/record/44806?ln=es https://inspirehep.net/record/49123?ln=es

*A 2012 presentation of S. V. Bolokhov includes an example that claims to derive colour from D=8 via Kaluza Klein in a torus with a non-flat metric. (Thanks Olaf Matyja for this reference) It refers to previous work for other Russian authors, perhaps justifying the torus+metric methodology

