in figure 3.

(400,80)(0,0) (0,80)(30,50) (0,20)(30,50) (30,50)(60,50)[3]{}[4]{} (60,50)(90,80) (60,50)(90,20) (70,60)(110,60)[3]{}[3]{} (200,80)(230,50) (200,20)(230,50) (230,50)(260,50)[3]{}[4]{} (260,50)(290,80) (260,50)(290,20) (270,40)(305,40)[3]{}[3]{} (65,65)\[\][$r$]{} (65,35)\[\][$\bar{r}$]{} (265,65)\[\][$b$]{} (265,35)\[\][$\bar{b}$]{} (115,65)\[\][$\bar{b}$]{} (115,55)\[\][$r$]{} (85,30)\[\][$\bar{r}$]{} (90,70)\[\][$b$]{} (315,45)\[\][$\bar{b}$]{} (315,35)\[\][$r$]{} (285,30)\[\][$\bar{r}$]{} (290,70)\[\][$b$]{}

The two diagrams will interfere and the two final states are identical. Thus, it is not possible to tell whether the quark or the antiquark emitted the gluon. Therefore it makes sense to regard the quark-antiquark pair as a color dipole, radiating coherently. In the region between the quark and the gluon, the blue and antiblue color separation will give rise to the emission of softer gluons. But in directions further away the emissions from blue and antiblue will interfere destructively. Therefore, in these directions, the emission of softer gluons will correspond to a red antired color dipole. In the restframe of the quark and the gluon however, emission of softer gluons corresponds to a blue antiblue color dipole. Therefore the emission of softer gluons corresponds to two independent color dipoles. This generalizes and a system of a quark, an antiquark and $n-1$ gluons will correspond, in the large $N_c$ limit, to a system of $n$ independent color dipoles. Each time a gluon is radiated a dipole splits into two new dipoles 