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arXiv · 2111.06442

Aspects of Gauss-Bonnet scalarisation of charged black holes

Carlos A. R. Herdeiro·Alexandre M. Pombo·Eugen Radu
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Abstract

The general relativity vacuum black holes (BHs) can be scalarised in models where a scalar field non-minimally couples to the Gauss-Bonnet (GB) invariant. Such GB scalarisation comes in two flavours, depending on the GB sign that triggers the phenomenon. Hereafter these two cases are termed GB$^\pm$ scalarisation. For vacuum BHs, only GB$^+$ scalarisation is possible in the static case, while GB$^-$ scalarisation is $spin$ induced. But for electrovacuum BHs, GB$^-$ is also $charged$ induced. We discuss the GB$^-$ scalarisation of Reissner-Nordstr\"om and Kerr-Newman BHs, discussing zero modes and constructing fully non-linear solutions. Some comparisons with GB$^+$ scalarisation are given. To assess the generality of the observed features, we also briefly consider the GB$^\pm$ scalarisation of stringy dilatonic BHs and coloured BHs which provide qualitative differences with respect to the electrovacuum case.

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Carlos A. R. Herdeiro, Alexandre M. Pombo, Eugen Radu. 2021-11-11. Aspects of Gauss-Bonnet scalarisation of charged black holes. https://arxiv.org/abs/2111.06442

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