Deep inelastic scattering, QCD, and generalized vector dominance

We provide a formulation of generalized vector dominance (GVD) for low-x deep-inelastic scattering that explicitly incorporates the γ*→q anti q transition and a QCD-inspired ansatz for the (q anti q)p forward-scattering amplitude. The destructive interference originally introduced in off-diagonal GVD is recovered in the present formulation and traced back to the generic structure of two-gluon-exchange as incorporated into the notion of colour transparency. Asymptotically, the transverse photoabsorption cross section behaves as (lnQ2)/Q2, implying a logarithmic violation of scaling for F2, while the longitudinal-to-transverse ratio decreases as 1/lnQ2. (orig.)