SIGNIFICANCE OF ZERO MODES IN PATH-INTEGRAL QUANTIZATION OF SOLITONICTHEORIES WITH BRST INVARIANCE

The significance of aero modes in the path integral quantization of so me solitonic models is investigated. In particular a Skyrme-like theor y with topological vortices in 1+2 dimensions is studied, and with a B RST-invariant gauge fixing a well-defined transition amplitude is obta ined in the one-loop approximation. We also present an alternative met hod which does not necessitate evoking the time dependence in the func tional integral, but is equivalent to the original one in dealing with the quantization in the background of the static classical solution o f the nonlinear field equations. The considerations given here are par ticularly useful in - but also limited to - the one-loop approximation .