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arXiv · hep-th/9208001

$SL(2,R)xSU(2)/R^2$ string model in curved spacetime and exact conformal results

I. Bars·K. Sfetsos
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Abstract

Pursuing further the recent methods in the algebraic Hamiltonian approach to gauged WZW models, we apply them to the bosonic SL(2,R) X SU(2)/R^2 model recently investigated by Nappi and Witten. We find the global space and compute the conformally exact metric and dilaton fields to all orders in the $1/k$ expansion. The semiclassical limit $k',k\to \infty$ of our exact results agree with the lowest order perturbation computation which was done in the Lagrangian formalism. We also discuss the supersymmetric type-II and heterotic versions of this model and verify the non-renormalization of $e^Φ\sqrt{-G}$.

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I. Bars, K. Sfetsos. 1992-08-02. $SL(2,R)xSU(2)/R^2$ string model in curved spacetime and exact conformal results. https://doi.org/10.1016/0370-2693(93)90686-c

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