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arXiv · 2410.00314

Instability of nonsingular black holes in nonlinear electrodynamics

Antonio De Felice·Shinji Tsujikawa
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Abstract

We show that nonsingular black holes realized in nonlinear electrodynamics are always prone to Laplacian instability around the center because of a negative squared sound speed in the angular direction. This is the case for both electric and magnetic BHs, where the instability of one of the vector-field perturbations leads to enhancing a dynamical gravitational perturbation in the even-parity sector. Thus, the background regular metric is no longer maintained in a steady state. Our results suggest that the construction of stable, nonsingular black holes with regular centers, if they exist, requires theories beyond nonlinear electrodynamics.

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Antonio De Felice, Shinji Tsujikawa. 2024-10-01. Instability of nonsingular black holes in nonlinear electrodynamics. https://doi.org/10.1103/physrevlett.134.081401

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