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Exact monopole instantons and cosmological solutions in string theory from abelian dimensional reduction

Adrian R. Lugo
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Abstract

We compute the exact string vacuum backgrounds corresponding to the non-compact coset theory $SU(2,1)/SU(2)$. The conformal field theory defined by the level $k= 4$ results in a five dimensional singular solution that factorizes in an asymptotic region as the linear dilaton solution and a $S^3$ model. It presents two abelian compact isometries that allow to reinterpreting it from a four dimensional point of view as a stationary and magnetically charged space-time resembling in some aspects the Kerr-Newman solution of general relativity. The $k=\frac{13}{7}$ theory on the other hand describes a cosmological solution that interpolates between a singular phase at short times and a $S^1 \times S^2$ universe after some planckian times.

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Adrian R. Lugo. 1997-02-17. Exact monopole instantons and cosmological solutions in string theory from abelian dimensional reduction. https://doi.org/10.1103/physrevd.55.6394

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