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arXiv · hep-th/9511071

Dilatonic Black Holes in Higher Curvature String Gravity

P. Kanti·N. E. Mavromatos·J. Rizos·K. Tamvakis·E. Winstanley
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Abstract

We give analytical arguments and demonstrate numerically the existence of black hole solutions of the $4D$ Effective Superstring Action in the presence of Gauss-Bonnet quadratic curvature terms. The solutions possess non-trivial dilaton hair. The hair, however, is of ``secondary" type", in the sense that the dilaton charge is expressed in terms of the black hole mass. Our solutions are not covered by the assumptions of existing proofs of the ``no-hair" theorem. We also find some alternative solutions with singular metric behaviour, but finite energy. The absence of naked singularities in this system is pointed out.

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P. Kanti, N. E. Mavromatos, J. Rizos, K. Tamvakis, E. Winstanley. 1995-11-10. Dilatonic Black Holes in Higher Curvature String Gravity. https://doi.org/10.1103/physrevd.54.5049

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