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arXiv · hep-th/9411190

Relevant Perturbations of the SU(1,1)/U(1) Coset

Oleg A. Soloviev
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Abstract

It is shown that the space of cohomology classes of the $SU(1,1)/U(1)$ coset at negative level $k$ contains states of relevant conformal dimensions. These states correspond to the energy density operator of the associated nonlinear sigma model. We exhibit that there exists a subclass of relevant operators forming a closed fusion algebra. We make use of these operators to perform renormalizable perturbations of the $SU(1,1)/U(1)$ coset. In the infra-red limit, the perturbed theory flows to another conformal model. We identify one of the perturbative conformal points with the $SU(2)/U(1)$ coset at positive level. {}From the point of view of the string target space geometry, the given renormalization group flow maps the euclidean black hole geometry described by the $SU(1,1)/U(1)$ coset into the sphere described by the $SU(2)/U(1)$ coset.

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Oleg A. Soloviev. 1994-11-25. Relevant Perturbations of the SU(1,1)/U(1) Coset. https://doi.org/10.1016/0550-3213(95)00040-y

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