Pre-quarks and fractional charges

Abstract

Gluons in a fractionally charged quark model, arising within a non-Abelian unified gauge theory, are likely to be massless of colour SU(3) is to serve as a good classification symmetry. Unless gluons are selectively confined and quarks are not, the absence of massless gluons in weak decays of hadrons would seem to argue against observable fractionally charged quarks. This, however, does not preclude the existence of fractionally charged pre-quarks (preons, objects of which integer-charged quarks may be composed). The authors remark that if pre-quarks carry charge +or-e/3, the flavour symmetry group must be larger than SU(4) (possible SU(6)), within the context of the Yang-Mills type of unified gauge theories.