  We report on the first determination of the shear forces quarks inside the
proton from experimental data on deeply virtual Compton scattering. The maximum
shear force of approximately 40 MeV/fm occurs near 0.6 fm from the proton
center, indicating where confinement forces may be strongest. On the
macroscopic scale of the earth surface, this force corresponds to the weight of
a mass of about 650 kg. The shear forces in the proton reverse direction at r =
0.45 fm from the center.
