Parton distribution functions from large Nc QCD

In the Bjorken limit, the tranverse momenta of partons can be treated perturbations. The non-perturbative part of the problem of determining Deep Inelastic structure functions becomes then that of solving two dimensional QCD (2DQCD). We show an isomorphism of 2DQCD with a bilocal field theory of hadrons (two dimensional Quantum HadronDynamics, 2DQHD). Baryons are topological solitons of this theory. The classical limit of 2DQHD is the large Nc limit of 2DQCD; by solving its equations of motion we can determine the structure function of the baryon. We compare the answer with measurements in neutrino scattering and get good agreement; also we find that the anti-quark content of the baryon is small in the limit of large Nc and small current quark mass