Scalar perturbations to naked singularities of perfect fluid

Junbin Li; Xi-Ping Zhu

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arXiv · 2505.20766

Scalar perturbations to naked singularities of perfect fluid

Junbin Li·Xi-Ping Zhu

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Abstract

In this paper, we study the instability of naked singularities arising in the Einstein equations coupled with isothermal perfect fluid. We show that the spherically symmetric self-similar naked singularities of this system, are unstable to trapped surface formation, under $C^{1,\alpha}$ perturbations of an external massless scalar field. We viewed this as a toy model in studying the instability of these naked singularities under gravitational perturbations in the original Einstein--Euler system which is non-spherically symmetric.

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Junbin Li, Xi-Ping Zhu. 2025-05-27. Scalar perturbations to naked singularities of perfect fluid. https://arxiv.org/abs/2505.20766

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