By using the general transport theory of a normal many-fermion system recently developed by Résibois, the collision term is calculated up to fourth order in a coupling parameter. It is shown that the higher order terms can be arranged into the form of the quasiparticle collision term suggested by Landau in the Fermi-liquid theory, except for the transformation operator introduced by Résibois to connect the particle description to the quasiparticle one. We also analyze the three-body collision operator in transport theory from the same quasiparticle point of view to the lowest nontrivial order in the coupling constant. It is shown that the anomalous terms in this operator contain the renormalization effects on the usual two-body collision operator.

• Received 30 July 1965

DOI:https://doi.org/10.1103/PhysRev.143.110