16-component theory of the spin-1 particle and its generalization to arbitrary spin

The criteria of validity of this theory are, among others, the nonrelativistic approximation, the classical approximation which gives the Thomas spin theory, and the values of the energy in a homogeneous magnetic field. In the tensorial form, this theory is more complicated than the 10-component Proca theory, but, in the matrix form, it is more convenient than the preceding theory using the Petiau--Duffin--Kemmer matrices, because only matrices obeying the Dirac conditions intervene. When the mass term is equal to zero (k=0), one can recover the Maxwell equations as a particular case. Finally, the theory may be easily generalized for an arbitrary spin of value J=n/2