Gravitational coset models

bstract The algebra A D − 3 + + + dimensionally reduces to the E D −1 symmetry algebra of (12 − D )-dimensional supergravity. An infinite set of five-dimensional gravitational objects embedded in D-dimensions is constructed by identifying the null geodesic motion on cosets embedded in the generalised Kac-Moody algebra A D − 3 + + + . By analogy with super-gravity these are bound states of dual gravitons. The metric interpolates continuously between exotic gravitational solutions generated by the action of an affine sub-group. We investigate mixed-symmetry fields in the brane sigma model, identify actions for the full interpolating bound state and investigate the dualisation of the bound state to a solution of the Einstein-Hilbert action via the Hodge dual on multiforms. We conclude that the Hodge dual is insufficient to reconstruct solutions to the Einstein-Hilbert action from mixed-symmetry tensors.