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Updated: Nov 25, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Spin-Induced Black Hole Spontaneous Scalarization
Alexandru Dima1,2, Enrico Barausse1,2,3, Nicola Franchini1,2
1SISSA, Via Bonomea 265, 34136 Trieste, Italy and INFN Sezione di Trieste.
Abstract:
We study scalar fields in a black hole background and show that, when the scalar is suitably coupled to curvature, rapid rotation can induce a tachyonic instability. This instability, which is the hallmark of spontaneous scalarization in the linearized regime, is expected to be quenched by nonlinearities and endow the black hole with scalar hair. Hence, our results demonstrate the existence of a broad class of theories that share the same stationary black hole solutions with general relativity at low spins, but which exhibit black hole hair at sufficiently high spins (a/M≳0.5). This result has clear implications for tests of general relativity and the nature of black holes with gravitational and electromagnetic observations.
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