Black hole hair formation in shift-symmetric generalised scalar-tensor gravity

Benkel, Robert; Sotiriou, Thomas P.; Witek, Helvi

Abstract

A linear coupling between a scalar field and the Gauss–Bonnet invariant is the only known interaction term between a scalar and the metric that: respects shift symmetry; does not lead to higher order equations; inevitably introduces black hole hair in asymptotically flat, 4-dimensional spacetimes. Here we focus on the simplest theory that includes such a term and we explore the dynamical formation of scalar hair. In particular, we work in the decoupling limit that neglects the backreaction of the scalar onto the metric and evolve the scalar configuration numerically in the background of a Schwarzschild black hole and a collapsing dust star described by the Oppenheimer–Snyder solution. For all types of initial data that we consider, the scalar relaxes at late times to the known, static, analytic configuration that is associated with a hairy, spherically symmetric black hole. This suggests that the corresponding black hole solutions are indeed endpoints of collapse.

Citation

Benkel, R., Sotiriou, T. P., & Witek, H. (2017). Black hole hair formation in shift-symmetric generalised scalar-tensor gravity. Classical and Quantum Gravity, 34(6), Article 064001. https://doi.org/10.1088/1361-6382/aa5ce7

• Journal Article Type: Article
• Acceptance Date: Jan 30, 2017
• Publication Date: Feb 20, 2017
• Deposit Date: Feb 27, 2017
• Publicly Available Date: Feb 27, 2017
• Journal: Classical and Quantum Gravity
• Print ISSN: 0264-9381
• Electronic ISSN: 1361-6382
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 34
• Issue: 6
• Article Number: 064001
• DOI: https://doi.org/10.1088/1361-6382/aa5ce7
• Public URL: https://nottingham-repository.worktribe.com/output/845081
• Publisher URL: http://dx.doi.org/10.1088/1361-6382/aa5ce7
• Additional Information: This is an author-created, un-copyedited version of an article accepted for publication in Classical and Quantum Gravity. The publisher is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at http://dx.doi.org/10.1088/1361-6382/aa5ce7
• Contract Date: Feb 27, 2017