Asymptotically flat black holes with scalar hair: a review

By Carlos A. R. Herdeiro, Eugen Radu. 2015

549 citations recorded by the source corpus.

We consider the status of black hole (BH) solutions with nontrivial scalar fields but no gauge fields, in four-dimensional asymptotically flat spacetimes, reviewing both classical results and recent developments. We start by providing a simple illustration on the physical difference between BHs in electro-vacuum and scalar-vacuum. Next, we review no-scalar-hair theorems. In particular, we detail an influential theorem by Bekenstein and stress three key assumptions: (1) The type of scalar field equation; (2) the spacetime symmetry inheritance by the scalar field and (3) an energy condition. Then, we list regular (on and outside the horizon), asymptotically flat BH solutions with scalar hair, organizing them by the assumption which is violated in each case and distinguishing primary from secondary hair. We provide a table summary of the state-of-the-art.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/8147e01509ba7b180957655b8a561a23c9cfb056

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Nuclear and High Energy Physics

In Statistical and Nonlinear Physics

Citations in the corpus

Born–Infeld inspired modifications of gravity (2017, background): “Two other interesting issues would be to investigate the existence of hairy black holes and superradiance, found in GR [206], in these theories43, as well as to extend the thermodynamic laws studied in other Palatini theories of gravity such as f(R) [38] to the Born-Infeld scenario.”
Shadows and strong gravitational lensing: a brief review (2018, background): “These BH solutions can moreover be perturbatively stable, asymptotically flat and regular, possessing a dilatonic field as a form of nonindependent hair [66, 83].”
Horndeski theory and beyond: a review (2019, background): “The no-hair theorem can thus be extended to cover a wider class of theories [263, 264], though it can certainly be evaded, e.”
Spontaneous scalarisation of charged black holes: coupling dependence and dynamical features (2019, background): “the reviews [12, 13] for different types of non-Kerr BHs.”
The 4D Einstein–Gauss–Bonnet theory of gravity: a review (2022, background): “In particular, they are expected to produce viable models of inflation in the early Universe, display spontaneous scalarization in compact objects, and admit novel black hole solutions that evade the no-hair theorems (see reference [56] for a review).”
Superradiance (2015, background): “2014 Asymptotically flat, hairy BH solutions are constructed analytically [109] and numerically [13, 110, 111].”