We argue that off-shell dualities between d=1 supermultiplets with different sets of physical bosonic components and the same number of fermionic ones are related to gauging some symmetries in the actions of the supermultiplets with maximal sets of physical bosons. Our gauging procedure uses off-shell superfields and so is manifestly supersym-metric. We focus on N =4 supersymmetric mechanics an...

It is shown that the asymmetric chiral gauging of the WZW models give rise to consistent string backgrounds. The target space structure of the [SL(2,R)/SO(1, 1)]L ⊗ [SL(2,R)/U(1)]R model is analyzed and the presence of a hidden isometry in this background is demonstrated. A nonlinear coordinate transformation is obtained which transforms the asymmetric model to the symmetric one, analyzed recen...

We review some of the recent developments in the construction of W-string theories. These are generalisations of ordinary strings in which the two-dimensional " worldsheet " theory, instead of being a gauging of the Virasoro algebra, is a gauging of a higher-spin extension of the Virasoro algebra—a W algebra. Despite the complexity of the (non-linear) W algebras, it turns out that the spectrum ...

We analyze the coset model (E c 2 × E c 2)/E c 2 and construct a class of exact string vacua which describe plane gravitational waves and their duals, generalizing the plane wave background found by Nappi and Witten. In particular, the vector gauging describes a two-parameter family of singular geometries with two isometries, which is dual to plane gravitational waves. In addition, there is a m...

We consider gauged WZWmodels based on a four dimensional non-semi-simple group. We obtain conformal σ-models in D = 3 spacetime dimensions (with exact central charge c = 3) by axially and vectorially gauging a one-dimensional subgroup. The model obtained in the axial gauging is related to the 3D black string after a correlated limit is taken in the latter model. By identifying the CFT correspon...

Scale-invariant actions in arbitrary dimensions are investigated in curved space to clarify the relation between scale-, Weyland conformal invariance on the classical level. The global Weyl-group is gauged. Then the class of actions is determined for which Weyl-gauging may be replaced by a suitable coupling to the curvature (Ricci gauging). It is shown that this class is exactly the class of ac...