  Weakly correlated electrons on a square lattice are studied by angle-resolved
functional renormalization group. Upon renormalization the interaction starts
to depend on momenta and has pole-like solutions near a doping-dependent
characteristic critical energy scale. Near half-filling this scale is the
pseudogap temperature T*. In the overdoped regime the critical scale is the
mean-field like critical temperature for d-wave superconductivity.
