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arXiv · 2409.11669

Spontaneous scalarization of Bardeen black holes

Lina Zhang·Qiyuan Pan·Yun Soo Myung·De-Cheng Zou
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Abstract

We study the spontaneous scalarization of Bardeen black holes, whose tachyonic instability triggers the formation of scalarized charged black holes (SCBHs). In this case, we find infinite ($n=0,1,2,\cdots$) branches of SCBHs with magnetic charge $g$. The $n = 0$ branch of SCBHs can be found for the coupling parameter $\alpha \geq \alpha_{n=0}(g)$ with both quadratic (1-$\alpha \varphi^2$) and exponential ($e^{-\alpha \varphi^2}$) couplings, where $\alpha_{n=0}(g)$ represents the threshold of tachyonic instability for the Bardeen black holes. Furthermore, it is shown that the $n = 0$ branch for both couplings is stable against radial perturbations. This stability shows that this branch can be used for further observational implications.

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Lina Zhang, Qiyuan Pan, Yun Soo Myung, De-Cheng Zou. 2024-09-18. Spontaneous scalarization of Bardeen black holes. https://arxiv.org/abs/2409.11669

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