  Recent developments of the covariant Bethe-Salpeter (BS) approach with the
use of the separable interaction for the deuteron are reviewed. It is shown
that the BS formalism allows a covariant description of various electromagnetic
reactions like the lepton-deuteron scattering, deuteron electro-disintegration,
deep inelastic scattering (DIS) of leptons on light nuclei. The procedure of
the construction of the separable nucleon-nucleon (NN) interaction is
discussed. The BS formalism facilitates analysis of the role of the P-waves
(negative energy components) in the electromagnetic properties of the deuteron
and its comparison with the nonrelativistic results. Furthermore the covariant
BS approach makes it possible to analyze DIS of leptons from the deuteron in a
model independent way and to extend the formalism to DIS reactions on the light
nuclei.
