From Nuclear Structure to Nucleon Structure

Similarities between nuclear structure study with many-body theory ap-proach and nucleon structure calculations with lattice QCD are pointed out. We will give an example of how to obtain the connected sea partons from a combination of the experimental data, a global fit of parton distribution functions and a lattice calculation. We also present a complete calculation of the quark and glue decomposition of the proton momentum and angular mo-mentum in the quenched approximation. It is found that the quark orbital angular momentum constitutes about 50 % of the proton spin