Simple BRST quantization of general gauge models

It is shown that the BRST charge Q for any gauge model with a Lie algebra symmetry may be decomposed as Q=δ+δ+, δ2=δ+2=0, [δ, δ+]+=0 provided dynamical Lagrange multipliers are used but without introducing other matter variables in δ than the gauge generators in Q. Furthermore, δ is shown to have the form δ=c+aφa (or φa'c+a) where ca are anticommuting expressions in the ghosts and Lagrange multipliers, and where the non-hermitian operators φa satisfy the same Lie algebra as the original gauge generators. By means of a bigrading the BRST condition reduces to δvertical strokeph>=δ+vertical strokeph>=0 which is naturally solved by cavertical strokeph>=φavertical strokeph>=0 (or c+avertical strokeph>=φa'vertical strokeph>=0). The general solutions are shown to have a very simple form. (orig.)