  Deep-inelastic scattering, in the laboratory and on the lattice, is most
instructive for understanding how the nucleon is built from quarks and gluons.
The long-term goal is to compute the associated structure functions from first
principles. So far this has been limited to model calculations. In this Letter
we propose a new method to compute the structure functions directly from the
virtual, all-encompassing Compton amplitude, utilizing the operator product
expansion. This overcomes issues of renormalization and operator mixing, which
so far have hindered lattice calculations of power corrections and higher
moments.
