  We considered Weinberg-like equations in the article [1] in order to
construct the Feynman-Dyson propagator for the spin-1 particles. This
construction is based on the concept of the Weinberg field as a system of four
field functions differing by parity and by dual transformations. We also
analyzed the recent controversy in the definitions of the Feynman-Dyson
propagator for the field operator containing the S=1/2 self/anti-self charge
conjugate states in the papers by D. Ahluwalia et al and by W. Rodrigues Jr. et
al. The solution to this mathematical controversy is obvious. I proposed the
necessary doubling of the Fock Space (as in the Barut and Ziino works), thus
extending the corresponding Clifford Algebra. Meanwhile, the N. Debergh et al
article considered our old ideas of doubling the Dirac equation, and other
forms of T- and PT-conjugation [5]. Both algebraic equation Det (\hat p - m) =0
and Det (\hat p + m) =0 for u- and v- 4-spinors have solutions with p_0= \pm
E_p =\pm \sqrt{{\bf p}^2 +m^2}. The same is true for higher-spin equations (or
they may even have more complicated dispersion relations). Meanwhile, every
book considers the equality p_0=E_p for both u- and v- spinors of the
(1/2,0)\oplus (0,1/2)) representation only, thus applying the
Dirac-Feynman-Stueckelberg procedure for elimination of negative-energy
solutions. It seems, that it is imposible to consider the relativistic quantum
mechanics appropriately without negative energies, tachyons and appropriate
forms of the discrete symmetries.
