The symmetry group of Feynman diagrams and consistency of the BPHZ renormalization scheme *

We study the relation between the symmetry group of a Feynman diagram and its reduced diagrams. We then prove that the counterterms in the BPHZ renormalization scheme are consistent with adding counterterms to the interaction Hamiltonian in all cases, including that of Feynman diagrams with symmetry factors.

Automated summary

The study examines the relationship between the symmetry group of a Feynman diagram and its reduced diagrams, and proves that counterterms in the BPHZ renormalization scheme are consistent with adding counterterms to the interaction Hamiltonian in all cases, including those with symmetry factors.