Summarizing DIS

Structure functions (observables) are identified with distribution functions (lightcone quark-quark correlators)
DF’s are quark densities that are directly linked to lightcone wave functions squared
There are three DF’s
f1q(x) = q(x), g1q(x) =q(x), h1q(x) =q(x)
Longitudinal gluons (A+, not seen in LC gauge) are absorbed in DF’s
Transverse gluons appear at 1/Q and are contained in (higher twist) qqG-correlators

Structure functions (observables) are identified with distribution functions (lightcone quark-quark correlators)