# QCD and SU(3)

Can you please specify a reference to help me understand how QCD explains the fact that all particles observed in nature transforms under SU(3).

fzero
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Not all particles transform under SU(3).

If searching around on wikipedia is insufficient for you, I'd suggest picking up an undergrad text on particle physics. D. Griffiths, "Introduction to Elementary Particles," is a particularly good one.

okay, thanks

Actually the statement "not all particles transform under SU(3)" could be misleading. All particles have a well-defined transformation property under SU(3)_color. Quarks for instance transform under the fundamental representation. Leptons belong to the trivial singlet representation, the identity, they are invariant under SU(3)_color rotations. Observed hadrons also are color singlet, this is essentially confinement. We can understand this property by hand-waving, but there is no definite mathematical, rigorous, proof of confinement.