  Description of time evolution of the relativistic unstable electromagnetic
system consisting of Fermi-Dirac particle interacting with electromagnetic
field, in the framework of the Liouville space extension of quantum mechanics
is done. The work was carried out on the basis of Prigogine's unified
formulation of quantum and kinetic dynamics. The eigenvalues problem for the
relativistic Hamiltonian of the electromagnetic system was solved. The obtained
results can be used as the ground for the further studies of the observed
physical processes such as bremsstrahlung, relaxation of excited states of
atoms and atomic nuclei, particles decay.
