Quark Model from Lattice QCD

We study the valence approximation in lattice QCD of hadrons where the cloud quarks and antiquarks are deleted by truncating the backward time propagation (Z graphs) in the connected insertions. Whereas, the sea quarks are eliminated via the quenched approximation and in the disconnected insertions. It is shown that the ratios of isovector to isoscalar matrix elements in the nucleon reproduce the SU(6) quark model predictions in a lattice QCD calculation. We also discuss how the hadron masses are affected.