Leontovich relations in thermal field theory
Theory Division, CERN, 1211 Geneva 23, Switzerland
Received: 17 April 2000 / Published online: 6 July 2000 - © Springer-Verlag 2000
The application of generalized Kramers-Kronig relations, the so-called Leontovich relations, to thermal field theory is discussed. Medium effects contained in the full, thermal propagators can easily be taken into account by this method. As examples the collisional energy loss of a charged particle in a relativistic plasma and the radiation of energetic photons from a quark-gluon plasma are considered. Within the leading logarithmic approximation the results based on the hard thermal loop resummation technique are reproduced easily. However, the method presented here is more general and provides exact expressions, which allow in principle non-perturbative calculations.
Copyright Società Italiana di Fisica, Springer-Verlag 2000