ABSTRACT
There is a tremendous amount of evidence from studies of high energy QCD that the quarks carry an attribute which we call color. Quarks come in three colors, and the colors interact with a set of 8 gluons in an SU(3) symmetric way. The SU(3) associated with the color interaction is called color SU(3). The gluons couple to color charges, that is the color SU(3) generators, just as the photon, the particle of light, couples to electric charge. The electromagnetic force between two objects is attractive when the product of their electric charges is negative. One difference with color is that there are 8 gluons, instead of one photon, and the color interaction between two colored particles is proportional to the sum of the products of their color charges.
