
VOLUME 20  ISSUE 2 
PAGE 135

Diagonality of the electron mass operators in a constant field
Ritus V.I.
On the basis of arguments of general character, a proof is presented of the diagonality of the exact (outside the framework of perturbation theory with respect to external and radiation fields) mass operator of an electron in a constant electromagnetic field. The diagonality of the mass operator radically simplifies the study of radiation effects in an external field and reduces the integrodifferential equations for the wave function and for the exact Green's function to algebraic equations.

