collaborators

9 papers

gr-qc2026

Kerr black holes with vector dark matter hair

Fredric Hancock, Helvi Witek

We consider a massive vector-field perturbation on a Kerr black hole background. We fix the field's density at the edge of the black hole sphere of influence to model a bath of wav…

gr-qc2026

Charged black holes embedded in matter with anisotropic pressure: Horizon Structure and Quasinormal Mode Spectra

D. N. Garzon, Jiayi Zhang, Elena Kopteva +1

In realistic settings, black holes are expected to be embedded in astrophysical environments. These environments, including possible dark matter distributions, can modify observabl…

gr-qc2026

Scalarization and descalarization in hyperbolic encounters of black holes

Frederick C. L. Pardoe, Helvi Witek

We use numerical relativity to study the scalar field evolution sourced by hyperbolic encounters of black holes in quadratic scalar Gauss-Bonnet gravity. In this theory, single bla…

gr-qc2026

Spin-up and mass-gain in hyperbolic encounters of spinning black holes

Healey Kogan, Frederick C. L. Pardoe, Helvi Witek

Scattering black holes spin up and gain mass through the re-absorption of orbital angular momentum and energy radiated in gravitational waves during their encounter. In this work,…

gr-qc2026

Black-hole hair from vector dark matter accretion

Fredric Hancock, Helvi Witek

We model a single black hole in equilibrium with a dark photon-cold dark matter environment. Representing the dark photon as a Proca field, we show that a Schwarzschild black hole…

gr-qc2026

Waveform Modelling for the Laser Interferometer Space Antenna

LISA Consortium Waveform Working Group, Niayesh Afshordi, Sarp Akçay +144

LISA, the Laser Interferometer Space Antenna, will usher in a new era in gravitational-wave astronomy. As the first anticipated space-based gravitational-wave detector, it will exp…