  The paper contains some preliminary results about the problem of Bose
condensation at zero temperature. It is shown that the usual picture of three
dimensional Bose condensation, the so called Bogoliubov approximation, can be
explained in terms of a renormalization group flow, showing asymptotic freedom
and anomalous (superfluid) behaviour of the two point correlation, at least
order by order in the running coupling constants.
