2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/83062Various perturbative and non-perturbative many-body techniques are discussed in this work. Especially, we will focus on the summation of so-called Parquet diagrams with emphasis on applications to finite nuclei. Here, the subset of two-body Parquet equations will be discussed. A practical implementation of the corresponding equations for studies of effective interactions for finite nuclei is outlined.55 pages, latex, to appear in Advances in many-body theory, vol 2Nuclear Theorytext