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arXiv · 2510.07263

Painlev\'{e}-Gullstrand coordinates for Kiselev black holes

Bijan Bagchi·Sauvik Sen
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Abstract

We investigate the implications provided by the modified Painlev\'{e}-Gullstrand coordinates in the context of quintessence for the Kiselev black hole. In this regard, we set up a fully static line element in terms of lapse and shift functions, apart from including the deformation parameter signaling deviation from the standard Painlev\'{e}-Gullstrand metric. We address two specific issues pertaining to the problems of radiation and dust furnished by the corresponding barotropic index parameter and study the related consequences by performing a range of analyses to explore the influence imposed by quintessence. We also discuss the thermodynamical consequences by evaluating the expressions of the Hawking temperature and the entropy function in closed forms.

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Bijan Bagchi, Sauvik Sen. 2025-10-08. Painlev\'{e}-Gullstrand coordinates for Kiselev black holes. https://arxiv.org/abs/2510.07263

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