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arXiv · 2502.04444

Nonradial stability of topological stars

Alexandru Dima·Marco Melis·Paolo Pani
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Abstract

Topological stars are regular, horizonless solitons arising from dimensional compactification of Einstein-Maxwell theory in five dimensions, which could describe qualitative properties of microstate geometries for astrophysical black holes. They also provide a compelling realization of ultracompact objects arising from a well-defined theory and display all the phenomenological features typically associated with black hole mimickers, including a (stable) photon sphere, long-lived quasinormal modes, and echoes in the ringdown. By completing a thorough linear stability analysis, we provide strong numerical evidence that these solutions are stable against nonradial perturbations with zero Kaluza-Klein momentum.

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Alexandru Dima, Marco Melis, Paolo Pani. 2025-02-06. Nonradial stability of topological stars. https://arxiv.org/abs/2502.04444

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