Ji found a new class of QCD hard scattering called Deep Exclusive Processes in lepton-nucleon collisions, which allows to probe the GPDs experimentally.
[4] Deep Exclusive Processes has been an important part of the experimental program at Jefferson Lab 12 GeV facility and the Electron-Ion Collider at Brookhaven National Laboratory.
In 2013, Ji found that the fundamental quantities charactering the high-energy properties of the nucleon, the parton distributions introduced by R. Feynman, can be directly calculated in Euclidean lattice field theory.
[5] He developed this into Large-Momentum Effective Theory or LaMET which allows parton physics or light-cone correlations computable from large momentum expansion of time-independent observables in lattice QCD.
[6] Ji was elected a fellow of the American Physical Society in 2000, "[f]or fundamental contributions to the understanding of the structure of the nucleon and the process of deeply virtual Compton scattering.