  The free Schroedinger theory in d space dimensions is a non-relativistic
conformal field theory. The interacting non-linear theory preserves this
symmetry in specific numbers of dimensions at the classical (tree) level. This
holds in particular for the Phi^4-theory in d = 2. We compute the full quantum
corrections to the 4-point function to show that the symmetry is broken by an
anomalous contribution proportional to the exact beta-function

High Energy Physics - Theory;Other Condensed Matter