THE SU(2) NONLINEAR SIGMA-MODEL IN 2- PERTURBATION-THEORY IN A POLYNOMIAL FORMULATION(1 DIMENSIONS )

We construct a perturbation theory for the SU(2) nonlinear sigma model in 2 + 1 dimensions using a polynomial, first-order formulation, wher e the variables are a non-Abelian vector field L(mu) [the left SU(2) c urrent], and a, non-Abelian pseudovector field theta(mu), which impose s the condition F-mu v(L) = 0. The coordinates on the group do not app ear in the Feynman rules, but their scattering amplitudes are easily r elated to those of the currents. We show that all the infinities affec ting physical amplitudes at one-loop order can be cured by normal-orde ring, presenting the calculation of the full propagator as an example of an application.