Effective field theory for dilute Fermi systems

The virtues of an effective field theory (EFT) approach to many-body proble ms are illustrated by deriving the expansion for the energy of an homogeneo us, interacting Fermi gas at low density and zero temperature. A renormaliz ation scheme based on dimensional regularization with minimal subtraction l eads to a more transparent power-counting procedure and diagrammatic expans ion than conventional many-body approaches. Coefficients of terms in the ex pansion with logarithms of the Fermi momentum are determined by the renorma lization properties of the EFT that describes few-body scattering. Lessons for an EFT treatment of nuclear matter are discussed. (C) 2000 Elsevier Sci ence B.V. All rights reserved.