  A derivative expansion of the Wegner-Houghton equation is derived for a
scalar theory. The corresponding full non-perturbative renormalization group
equations for the potential and the wave-function renormalization function are
presented. We also show that the two loop perturbative anomalous dimension for
the O(N) theory can be obtained by means of a polynomial truncation in the
field dependence in our equations.

High Energy Physics - Theory;Condensed Matter;High Energy Physics - Phenomenology