NONEQUILIBRIUM QUANTUM-FIELD THEORY AND PERTURBATION-THEORY

Authors
FAUSER R WOLTER HH
Citation
R. Fauser et Hh. Wolter, NONEQUILIBRIUM QUANTUM-FIELD THEORY AND PERTURBATION-THEORY, Nuclear physics. A, 584(4), 1995, pp. 604-620
Citations number
16
Categorie Soggetti
Physics, Nuclear
Journal title
Nuclear physics. A → ACNP
ISSN journal
03759474
Volume
584
Issue
4
Year of publication
1995
Pages
604 - 620
Database
ISI
SICI code
0375-9474(1995)584:4<604:NQTAP>2.0.ZU;2-K
Abstract
The perturbation theory is studied for a non-equilibrium situation of an interacting fermion-boson system. The structure of the Green functi on expansion is represented in the Keldysh-Schwinger formalism. A non- equilibrium Wick theorem is derived by expressing the expectation valu es of normal-ordered products, which do not vanish in non-equilibrium, in terms of Wightman functions and finally in terms of correlation fu nctions.