Many-body theory of degenerate systems
Strongly Correlated Electrons
2007-05-23 v2
Abstract
The many-body theory of degenerate systems is described in detail. More generally, this theory applies to systems with an initial state that cannot be described by a single Slater determinant. The double-source (or closed-time-path) formalism of nonequilibrium quantum field theory is used to derive an expression for the average value of a product of interacting fields when the initial state is not the vacuum or a Slater determinant. Quantum group techniques are applied to derive the hierarchy of unconnected Green functions and the hierarchy of connected ones.
Keywords
Cite
@article{arxiv.cond-mat/0309558,
title = {Many-body theory of degenerate systems},
author = {Christian Brouder},
journal= {arXiv preprint arXiv:cond-mat/0309558},
year = {2007}
}
Comments
27 pages