Physics – Nuclear Physics – Nuclear Theory
Scientific paper
1995-02-14
Ann.Phys.245:311-338,1996
Physics
Nuclear Physics
Nuclear Theory
32 pages, no figures, standard Latex
Scientific paper
10.1006/aphy.1996.0011
We investigate the relationship between the covariant and the three-dimensional (equal-time) formulations of quantum kinetic theory. We show that the three-dimensional approach can be obtained as the energy average of the covariant formulation. We illustrate this statement in scalar and spinor QED. For scalar QED we derive Lorentz covariant transport and constraint equations directly from the Klein-Gordon equation rather than through the previously used Feshbach-Villars representation. We then consider pair production in a spatially homogeneous but time-dependent electric field and show that the pair density is derived much more easily via the energy averaging method than in the equal-time representation. Proceeding to spinor QED, we derive the covariant version of the equal-time equation derived by Bialynicki-Birula et al. We show that it must be supplemented by another self-adjoint equation to obtain a complete description of the covariant spinor Wigner operator. After spinor decomposition and energy average we study the classical limit of the resulting three-dimensional kinetic equations. There are only two independent spinor components in this limit, the mass density and the spin density, and we derive also their covariant equations of motion. We then show that the equal-time kinetic equation provides a complete description only for constant external electromagnetic fields, but is in general incomplete. It must be supplemented by additional constraints which we derive explicitly from the covariant formulation.
Heinz Ulrich
Zhuang Peng-fei
No associations
LandOfFree
Relativistic Quantum Transport Theory for Electrodynamics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Relativistic Quantum Transport Theory for Electrodynamics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relativistic Quantum Transport Theory for Electrodynamics will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-106394