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The electrogravity transformation and global monopoles in scalar-tensor gravity

Sukanta Bose·Naresh Dadhich
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Abstract

The electrogravity transformation is defined by an interchange of the ``active'' and ``passive'' electric parts of the Riemann tensor. Such a transformation has been used to find new solutions that are ``dual'' to the Kerr family of black hole spacetimes in general relativity. In such a case, the dual solution is a similar black hole spacetime endowed with a global monopole charge. Here, we extend this formalism to obtain solutions dual to the static, spherically symmetric solutions of two different scalar-tensor gravity theories. In particular, we first study the duals of the charged black hole solutions of a four-dimensional low-energy effective action of heterotic string theory. Next, we study dual of the Xanthopoulos-Zannias solution in Brans-Dicke theory, which contains a naked singularity. We show that, analogous to general relativity, in these scalar-tensor gravity theories the dual solutions are similar to the original spacetimes, but with a global monopole charge.

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Sukanta Bose, Naresh Dadhich. 2000-01-19. The electrogravity transformation and global monopoles in scalar-tensor gravity. https://doi.org/10.1016/s0370-2693(00)01187-4

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