Webinar :: Multiple solutions and the limits of the self-consistent approach in many-body perturbation theory (Walter Tarantino)

Thursday 18 February 2021, 14:00

Walter Tarantino

Perturbation theory using self-consistent Green’s functions is at the basis of widely used methods such as Hartree-Fock, GW, and Dynamical Mean field theory. In recent years, numerical studies on model hamiltonians have highlighted unexpected features of the approach that were interpreted as signs of its failure. In this seminar those results will be re-examined and a different interpretation in terms of functional domains will be offered. From such a perspective, the approach holds up at a formal level, but has its limitations from a computation point of view. Possible ways to overcome these limits will also be discussed.