Fermionic linearization scheme with Clifford variables

We propose an alternative interpretation of the fermi linarization approach to interacting electron systems, based on the requirement that the coefficients of the linearized operators are Clifford-like variables, whose anticommutator equals an unknown constant c. We apply the approximation to the Falicov-Kimball model, explicitly solving the self-consistency equation for the unknown, which turns out to behave as an order parameter. We discuss its relation with a metal-insulator transition and some thermodynamical quantities. In particular we show that our approximation in the T = 0 limit reproduces exactly the Gutzwiller results for the Hubbard model.