The many-body Green function of degenerate systems
Strongly Correlated Electrons
2010-07-28 v2 Mathematical Physics
math.MP
Abstract
A rigorous non perturbative adiabatic approximation of the evolution operator in the many-body physics of degenerate systems is derived. This approximation is used to solve the long-standing problem of the choice of the initial states of H0 leading to eigenstates of H0+V for degenerate systems. These initial states are eigenstates of P0 V P0, where P0 is the projection onto a degenerate eigenspace of H0. This result is used to give the proper definition of the Green function, the statistical Green function and the non-equilibrium Green function of degenerate systems. The convergence of these Green functions is established.
Keywords
Cite
@article{arxiv.0906.2052,
title = {The many-body Green function of degenerate systems},
author = {Christian Brouder and Gianluca Panati and Gabriel Stoltz},
journal= {arXiv preprint arXiv:0906.2052},
year = {2010}
}
Comments
4 pages, 1 figure