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arXiv · 1504.07657

Dilatonic dyon black hole solutions

M. E. Abishev·K. A. Boshkayev·V. D. Dzhunushaliev·V. D. Ivashchuk
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Abstract

Dilatonic black hole dyon solutions with arbitrary dilatonic coupling constant $\lambda \neq 0$ and canonical sign $\varepsilon = +1$ for scalar field kynetic term are considered. These solutions are defined up to solutions of two master equations for moduli funtions. For $\lambda^2 \neq 1/2$ the solutions are extended to $\varepsilon = \pm 1$, where $\varepsilon = -1$ corresponds to ghost (phantom) scalar field. Some physical parameters of the solutions: gravitational mass, scalar charge, Hawking temperature, black hole area entropy and parametrized post-Newtonian (PPN) parameters $\beta$ and $\gamma$ are obtained. It is shown that PPN parameters do not depend on scalar field coupling $\lambda$ and $\varepsilon$. Two group of bounds on gravitational mass and scalar charge (for fixed and arbitrary extremality parameter $\mu >0$) are found by using a certain conjecture on parameters of solutions when $1 +2 \lambda^2 \varepsilon > 0$. These bounds are verified numerically for certain examples. By product we are led to well-known lower bound on mass which was obtained earlier by Gibbons, Kastor, London, Townsend and Traschen by using spinor techniques.

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M. E. Abishev, K. A. Boshkayev, V. D. Dzhunushaliev, V. D. Ivashchuk. 2015-04-28. Dilatonic dyon black hole solutions. https://arxiv.org/abs/1504.07657

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