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arXiv · hep-th/9501055

Homogeneous Conformal String Backgrounds

M. Gasperini·R. Ricci
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Abstract

We present exact solutions characterised by Bianchi-type I,II,III,V,VI four-dimensional metric, space-independent dilaton, and vanishing torsion background, for the low energy string effective action with zero central charge deficit. We show that, in such a context, curvature singularities cannot be avoided, except for the trivial case of flat spacetime and constant dilaton. We also provide a further example of the failure of the standard prescription for connecting conformal string backgrounds through duality transformations associated to non-semisimple, non-Abelian isometry group.

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M. Gasperini, R. Ricci. 1995-01-13. Homogeneous Conformal String Backgrounds. https://doi.org/10.1088/0264-9381%2F12%2F3%2F006

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