  A full non-perturbative treatment of gauge theories requires to include
matter fields on equal footing with the gauge fields. Scalar matter can act as
a role model for generic matter, as many questions, e.g. confinement, can be
posed without referring to a particular Lorentz structure. Due to their rather
simple structure they are also useful to develop methods.
  One possible way to describe gauge theories beyond perturbation theory is
based on correlation functions. After a short discussion of the setup, lattice
gauge theory is used to analyze the interaction of gluons with quenched
fundamental and adjoint scalars. Both the two-point and three-point correlation
functions for massive and massless adjoint and fundamental scalars will be
determined, in minimal Landau gauge. The findings are in agreement with the
possibility that scalars are only slightly affected by the interaction with
gluons. The results are compared briefly with dynamical, massive scalars,
showing no significant changes in the confinement region compared to the
quenched case.
