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arXiv · 1509.01667

Spacetimes with a separable Klein-Gordon equation in higher dimensions

Ivan Kolar·Pavel Krtous
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Abstract

We study spacetimes that lead to a separable Klein-Gordon equation in a general dimension. We introduce an ansatz for the metric in higher dimensions motivated by analogical work by Carter in four dimensions and find solutions of the Klein-Gordon equation. For such a metric we solve the Einstein equations and regain the Kerr-NUT-(A)dS spacetime as one of our results. Other solutions lead to the Einstein-Kähler metric of a Euclidean signature. Next we investigate a warped geometry of two Klein-Gordon separable spaces with a properly chosen warped factor. We show that the resulting metric leads also to a separable Klein--Gordon equation and we find the corresponding solutions. Finally, we solve the Einstein equations for the warped geometry and obtain new solutions.

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Ivan Kolar, Pavel Krtous. 2016-02-08. Spacetimes with a separable Klein-Gordon equation in higher dimensions. https://doi.org/10.1103/physrevd.93.024053

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