Embedding Gauss-Bonnet scalarization models in higher dimensional topological theories

Abstract

In the presence of appropriate non-minimal couplings between a scalar field and the curvature squared Gauss-Bonnet (GB) term, compact objects such as neutron stars and black holes (BHs) can spontaneously scalarize, becoming a preferred vacuum. Such strong gravity phase transitions have attracted considerable attention recently. The non-minimal coupling functions that allow this mechanism are, however, always postulated ad hoc. Here we point out that families of such functions naturally emerge in the context of Higgs--Chern-Simons gravity models, which are found as dimensionally descents of higher dimensional, purely topological, Chern-Pontryagin non-Abelian densities. As a proof of concept, we study spherically symmetric scalarized BH solutions in a particular Einstein-GB-scalar field model, whose coupling is obtained from this construction, pointing out novel features and caveats thereof. The possibility of vectorization is also discussed, since this construction also originates vector fields non-minimally coupled to the GB invariant.

12 pages, 3 figures

References in corpus (10)

• Spontaneously scalarised Kerr black holes
• Self-interactions and Spontaneous Black Hole Scalarization
• Gauss-Bonnet black holes with a massive scalar field
• Polar quasinormal modes of the scalarized Einstein-Gauss-Bonnet black holes
• On the dynamics of the nonrotating and rotating black hole scalarization
• Spontaneous scalarization of Gauss-Bonnet black holes: Analytic treatment in the linearized regime
• The onset of spontaneous scalarization in generalised scalar-tensor theories
• Spontaneous scalarization of black holes in the Horndeski theory
• Spontaneous scalarization of Gauss-Bonnet black holes surrounded by massive scalar fields
• Collective scalarization or tachyonization: when averaging fails