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arXiv · 1512.05476

Rotating black hole and quintessence

Sushant G. Ghosh
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Abstract

We discuss spherically symmetric exact solutions of the Einstein equations for quintessential matter surrounding a black hole, which has an additional parameter ($ω$) due to the quintessential matter, apart from the mass ($M$). In turn, we employ the Newman\(-\)Janis complex transformation to this spherical quintessence black hole solution and present a rotating counterpart that is identified, for $α=-e^2 \neq 0$ and $ω=1/3$, exactly as the Kerr\(-\)Newman black hole, and as the Kerr black hole when $α=0$. Interestingly, for a given value of parameter $ω$, there exists a critical rotation parameter ($a=a_{E}$), which corresponds to an extremal black hole with degenerate horizons, while for $a a_{E}$. We find that the extremal value $a_E$ is also influenced by the parameter $ω$ and so is the ergoregion.

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Sushant G. Ghosh. 2016-03-30. Rotating black hole and quintessence. https://doi.org/10.1140/epjc%2Fs10052-016-4051-7

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