Confinement and Light-Front QCD

Numerical results for the (rest-frame) $Q\bar{Q}$ potential in light-front quantized $QCD_{2+1}$ on a $\perp$ lattice are presented. Both in the longitudinal as well as the $\perp$ spatial directions one obtains linear confinement. The confinement mechanism in light-front QCD depends on the orientation of the external charges: for longitudinally (with respect to the boost direction in the infinite momentum frame) separated quarks, confinement arises from the instantaneous interaction piece in the Hamiltonian while for $\perp$ separated quarks, the confinement mechanism is similar to the one in Hamiltonian lattice QCD. Nevertheless, already a very simple ansatz for the effective link-field potential yields an almost rotationally symmetric $Q\bar{Q}$ potential. The momentum carried by the glue strongly depends on the orientation ("polarization") of the $Q\bar{Q}$ pair.