  We present a framework where first principles calculations of jet
modification may be carried out in a non-perturbative thermal environment. As
an example of this approach, we compute the leading order contribution to the
transverse momentum broadening of a high energy (near on-shell) quark in a
thermal medium. This involves a factorization of a non-perturbative operator
product from the perturbative process of scattering of the quark. An operator
product expansion of the non-perturbative operator product is carried out and
related via dispersion relations to the expectation of local operators. These
local operators are then evaluated in quenched SU(2) lattice gauge theory.
