arXiv subjects
Publications and source records attributed to S. A. Garnov.
The gauge invariant method for calculation of the effective action of the local composite fields in QFT is proposed. The effective action of the local composite fields in QED is studied up to 2-loop level. The graph rules for the local composite fields are derived. On the basis of these rules the problem of one-particle irreducibility is discussed.
The 3-loop effective action and effective potential in Nambu - Jona-Lasinio model are calculated. The problem of vanishing contributions in the higher orders is discussed. The general form of such contributions is obtained.
The representation of the bare parameters of Lagrangian in terms of total vertex Green's functions is used to obtain the general form of renormalization conditions. In the framework of this approach renormalizations can be carried out without treatment to Feynman diagrams.