Conformal (p, q) supergeometries in two dimensions

Abstract

We propose a superspace formulation for conformal (p, q) supergravity in two dimensions as a gauge theory of the superconformal group OSp0(p|2; ℝ) × OSp0(q|2; ℝ) with a flat connection. Upon degauging of certain local symmetries, this conformal superspace is shown to reduce to a conformally flat SO(p) × SO(q) superspace with the following properties: (i) its structure group is a direct product of the Lorentz group and SO(p) × SO(q); and (ii) the residual local scale symmetry is realised by super-Weyl transformations with an unconstrained real parameter. As an application of the formalism, we describe mathcal{N} -extended AdS superspace as a maximally symmetric supergeometry in the p = q ≡ mathcal{N} case. If at least one of the parameters p or q is even, alternative superconformal groups and, thus, conformal superspaces exist. In particular, if p = 2n, a possible choice of the superconformal group is SU(1, 1|n) × OSp0(q|2; ℝ), for n ≠ 2, and PSU(1, 1|2) × OSp0(q|2; ℝ), when n = 2. In general, a conformal superspace formulation is associated with a supergroup G = GL× GR, where the simple supergroups GL and GR can be any of the extended superconformal groups, which were classified by Günaydin, Sierra and Townsend. Degauging the corresponding conformal superspace leads to a conformally flat HL× HR superspace, where HL (HR) is the R-symmetry subgroup of GL (GR). Additionally, for the p, q ≤ 2 cases we propose composite primary multiplets which generate the Gauss-Bonnet invariant and supersymmetric extensions of the Fradkin-Tseytlin term.