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arXiv · 2512.02506

Non-vanishing non-linear Static Love Number of a Class of Extremal Reissner-Nordstrom Black Holes

L. R. Gounis·A. Kehagias·G. Panagopoulos·A. Riotto
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Abstract

We compute the tidal Love numbers for a particular axially symmetric configuration of extremal Reissner-Nordstrom geometry. By exactly solving the non-linear Einstein equations, we investigate the tidal response of extremal Reissner-Nordstrom black holes in four-dimensional spacetimes under external gravitational fields. We show that, for the specific geometry considered, the static tidal Love number remains finite and non-vanishing to all orders in the external tidal field. By contrast, we verify that the Love number of an isolated extremal Reissner-Nordstrom black hole remains zero, in agreement with previous expectations. Furthermore, we explicitly calculate the Zerilli-Moncrief master functions and match them with the effective field theory description.

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L. R. Gounis, A. Kehagias, G. Panagopoulos, A. Riotto. 2025-12-02. Non-vanishing non-linear Static Love Number of a Class of Extremal Reissner-Nordstrom Black Holes. https://arxiv.org/abs/2512.02506

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