Relativistic many-body XMCD theory including core degenerate effects

Many-body theory of degenerate systems

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 ...

Causality in Relativistic Many Body Theory

Dirac sea effects are perhaps the most interesting characteristic of relativistic many body theory. In nuclear matter e.g. the effective mass of the nucleons and their coupling to the mesons undergo considerable corrections due to vacuum fluctuations [1], [2]. In addition, relativistic many body theory predicts strong corrections of the properties of hadrons at high nuclear matter densities. Un...

Nonequilibrium Relativistic Quantum Many-Body Theory

Many-body theory of degenerate systems: A simple example

Christian Brouder Laboratoire de Minéralogie Cristallographie, CNRS UMR 7590, Universités Paris 6 et 7, IPGP, case 115, 4 place Jussieu, 75252 Paris cedex 05, France. (Dated: February 2, 2008) The hierarchy of Green functions for (quasi)degenerate systems, presented in cond-mat/0308058, is calculated in detail for the case of a system with closed shells plus a single electron in a two-fold dege...

Radiative heat transfer: many-body effects

Heat transfer by electromagnetic radiation is one of the common methods of energy transfer between objects. Using the fluctuation-dissipation theorem, we have studied the effect of particle arrangement in the transmission of radiative heat in many-body systems. In order to show the effect of the structure morphology on the collective properties, the radiative heat transfer is studied and the re...