A derivation of the marginal Fermi liquid from first class constraints

A new method based on Dirac's method for first class constraints is introduced for solving the problem of exclusion of double occupancy. In the language of quantum constraints we demand that the pair operator Q(x⇒)=ψ↓(x⇒)ψ↑(x⇒) annihilates the ground state |Ψ0〉. As a result of the projection a time dependent action is generated and is investigated with the help of the renormalization group. We identify the marginal Fermi liquid with the properties: (a) The excitations spectrum is asymmetric between electrons and holes; we believe this asymmetry is the origin of the asymmetry observed in the tunneling density of states. (b) The imaginary part of the self-energy 1/τ∝ω is linear in the frequency at T=0 as observed experimentally.