We study the nonlinear dynamics of black holes that carry scalar hair and binaries composed of such black holes. The scalar hair is due to a linear or exponential coupling between the scalar and the Gauss-Bonnet invariant. We work perturbatively in the coupling constant of that interaction but nonperturbatively in the fields. We first consider the dynamical formation of hair for isolated black holes of arbitrary spin and determine the final state. This also allows us to compute for the first time the scalar quasinormal modes of rotating black holes in the presence of this coupling. We then study the evolution of nonspinning black hole binaries with various mass ratios and produce the first scalar waveform for a coalescence. An estimate of the energy loss in scalar radiation and the effect this has on orbital dynamics and the phase of gravitational waves (GWs) (entering at quadratic order in the coupling) shows that GW detections can set the most stringent constraint to date on theories that exhibit a coupling between a scalar field and the Gauss-Bonnet invariant.

Black holes and binary mergers in scalar Gauss-Bonnet gravity: Scalar field dynamics

Gualtieri L.;
2019

Abstract

We study the nonlinear dynamics of black holes that carry scalar hair and binaries composed of such black holes. The scalar hair is due to a linear or exponential coupling between the scalar and the Gauss-Bonnet invariant. We work perturbatively in the coupling constant of that interaction but nonperturbatively in the fields. We first consider the dynamical formation of hair for isolated black holes of arbitrary spin and determine the final state. This also allows us to compute for the first time the scalar quasinormal modes of rotating black holes in the presence of this coupling. We then study the evolution of nonspinning black hole binaries with various mass ratios and produce the first scalar waveform for a coalescence. An estimate of the energy loss in scalar radiation and the effect this has on orbital dynamics and the phase of gravitational waves (GWs) (entering at quadratic order in the coupling) shows that GW detections can set the most stringent constraint to date on theories that exhibit a coupling between a scalar field and the Gauss-Bonnet invariant.
Witek, H.; Gualtieri, L.; Pani, P.; Sotiriou, T. P.
File in questo prodotto:
File Dimensione Formato  
1148320.pdf

solo utenti autorizzati

Tipologia: Versione finale editoriale
Licenza: NON PUBBLICO - accesso privato/ristretto
Dimensione 1.02 MB
Formato Adobe PDF
1.02 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11568/1148320
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 84
  • ???jsp.display-item.citation.isi??? 79
social impact