THE FIELD-THEORY OF NONSUPERSYMMETRIC BRANE CONFIGURATIONS

We identify the 4d field theories living on the world-volume of D4-bra nes in non-supersymmetric type IIA string theory constructions. They a re softly broken N = 2. SQCD with the breakings introduced through vev s of the auxiliary fields in the spurion coupling field. Exact solutio ns of these theories for perturbing soft breakings exist in the litera ture. We calculate the ratios of string tensions in softly broken N = 2 SU(N) gauge theory testing the recently proposed M-theory prediction . The semi-classical result of M-theory is renormalized in the non-sup ersymmetric models. (C) 1998 Elsevier Science B.V.