The Spin Asymmetries of the Nucleon Experiment (SANE) measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 GeV and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40 • and covered a wide range in Bjorken x (0.3 < x < 0.8). Proportional to an average color Lorentz force, the twist-3 matrix element,d p 2 , was extracted from the measured asymmetries at Q 2 values ranging from 2.0 to 6.0 GeV 2 . The data display the opposite sign compared to most quark models, including the lattice QCD result, and an apparently unexpected scale dependence. Furthermore when combined with the neutron data in the same Q 2 range the results suggest a flavor independent average color Lorentz force.Today, it is accepted that Quantum Chromodynamics (QCD), the gauge theory of strong interactions, plays a central role in our understanding of nucleon structure at the heart of most visible matter in the universe. QCD successfully describes many observables in high energy scattering processes where the coupling among the con-fined constituents of hadrons (quarks and gluons) is weak and perturbative (pQCD) calculations are possible, taking advantage of factorization theorems and evolution equations similar to quantum electrodynamics (QED). At the same time, QCD offers a clear path to unravel the non-perturbative structure of hadrons using lattice QCD, arXiv:1805.08835v4 [nucl-ex]

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