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arXiv · 2303.04107

Quadrupole instability of static scalarized black holes

Burkhard Kleihaus·Jutta Kunz·Tim Utermöhlen·Emanuele Berti
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Abstract

The addition of a Ricci coupling to Einstein-scalar-Gauss-Bonnet theories makes general relativity a cosmological attractor. Previous work considered a quadratic coupling function with two independent coupling constants in such theories and showed that static, spherically symmetric, spontaneously scalarized black holes are radially stable beyond a critical value of the Ricci coupling constant. Here we demonstrate that these black holes are affected by a quadrupole instability which leads to two new branches of static, axially symmetric scalarized black holes. We discuss the properties of these solutions and provide embedding diagrams.

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Burkhard Kleihaus, Jutta Kunz, Tim Utermöhlen, Emanuele Berti. 2023-03-07. Quadrupole instability of static scalarized black holes. https://doi.org/10.1103/physrevd.107.l081501

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