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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…
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…
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…
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,…
Dephasing in binary black hole mergers surrounded by scalar wave dark matter clouds
Cheng-Hsin Cheng, Giuseppe Ficarra, Helvi Witek
Scalar fields of masses between and can exhibit enhanced gravitational interactions with black holes, and form scalar clouds around the…
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…
The Science of the Einstein Telescope
Adrian Abac, Raul Abramo, Simone Albanesi +485
Einstein Telescope (ET) is the European project for a gravitational-wave (GW) observatory of third-generation. In this paper we present a comprehensive discussion of its science ob…
Growing black-hole hair in nonminimally coupled biscalar gravity
Chloe Richards, Alexandru Dima, Deborah Ferguson +1
Black holes offer a unique laboratory for fundamental physics and are crucial for probing theories beyond Einstein's theory of General Relativity. In this paper, we consider 4D eff…
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…
Black Holes in Massive Dynamical Chern-Simons gravity: scalar hair and quasibound states at decoupling
Chloe Richards, Alexandru Dima, Helvi Witek
Black holes have a unique sensitivity to the presence of ultralight matter fields or modifications of the underlying theory of gravity. In the present paper we combine both feature…
How Do Axisymmetric Black Holes Grow Monopole and Dipole Hair?
Abhishek Hegade K R, Elias R. Most, Jorge Noronha +2
We study the dynamical formation of scalar monopole and dipole hair in scalar Gauss-Bonnet theory and dynamical Chern-Simons theory. We prove that the spherically-symmetric mode of…
Spin-induced dynamical scalarization, de-scalarization and stealthness in scalar-Gauss-Bonnet gravity during black hole coalescence
Matthew Elley, Hector O. Silva, Helvi Witek +1
Particular couplings between a scalar field and the Gauss-Bonnet invariant lead to spontaneous scalarization of black holes. Here we continue our work on simulating this phenomenon…
New Horizons for Fundamental Physics with LISA
K. G. Arun, Enis Belgacem, Robert Benkel +138
The Laser Interferometer Space Antenna (LISA) has the potential to reveal wonders about the fundamental theory of nature at play in the extreme gravity regime, where the gravitatio…
The problem with Proca: ghost instabilities in self-interacting vector fields
Katy Clough, Thomas Helfer, Helvi Witek +1
Massive vector fields feature in several areas of particle physics, e.g., as carriers of weak interactions, dark matter candidates, or as an effective description of photons in a p…
Snowmass2021 Cosmic Frontier White Paper: Numerical relativity for next-generation gravitational-wave probes of fundamental physics
Francois Foucart, Pablo Laguna, Geoffrey Lovelace +2
The next generation of gravitational-wave detectors, conceived to begin operations in the 2030s, will probe fundamental physics with exquisite sensitivity. These observations will…
How Do Spherical Black Holes Grow Monopole Hair?
Abhishek Hegade K. R., Elias R. Most, Jorge Noronha +2
Black holes in certain modified gravity theories that contain a scalar field coupled to curvature invariants are known to possess (monopole) scalar hair while non-black-hole spacet…
The missing link in gravitational-wave astronomy: A summary of discoveries waiting in the decihertz range
Manuel Arca Sedda, Christopher P L Berry, Karan Jani +25
Since 2015 the gravitational-wave observations of LIGO and Virgo have transformed our understanding of compact-object binaries. In the years to come, ground-based gravitational-wav…
Petrov Type, Principal Null Directions, and Killing Tensors of Slowly-Rotating Black Holes in Quadratic Gravity
Caroline B. Owen, Nicolás Yunes, Helvi Witek
The ability to test general relativity in extreme gravity regimes using gravitational wave observations from current ground-based or future space-based detectors motivates the math…
Square Peg in a Circular Hole: Choosing the Right Ansatz for Isolated Black Holes in Generic Gravitational Theories
Yiqi Xie, Jun Zhang, Hector O. Silva +3
The metric of a spacetime can be greatly simplified if the spacetime is circular. We prove that in generic effective theories of gravity, the spacetime of a stationary, axisymmetri…
Dynamical descalarization in binary black hole mergers
Hector O. Silva, Helvi Witek, Matthew Elley +1
Scalar fields coupled to the Gauss-Bonnet invariant can undergo a tachyonic instability, leading to spontaneous scalarization of black holes. Studies of this effect have so far bee…
Nonlinear curvature effects in gravitational waves from inspiralling black hole binaries
Banafsheh Shiralilou, Tanja Hinderer, Samaya Nissanke +2
Gravitational waves (GWs) from merging black holes allow for unprecedented probes of strong-field gravity. Testing gravity in this regime requires accurate predictions of gravitati…
Evolution of black hole shadows from superradiance
Gastón Creci, Stefan Vandoren, Helvi Witek
Black holes have turned into cosmic laboratories to search for ultra-light scalars by virtue of the superradiant instability. In this paper we present a detailed study of the impac…
Towards numerical relativity in scalar Gauss-Bonnet gravity: 3+1 decomposition beyond the small-coupling limit
Helvi Witek, Leonardo Gualtieri, Paolo Pani
Scalar Gauss-Bonnet gravity is the only theory with quadratic curvature corrections to general relativity whose field equations are of second differential order. This theory allows…
Prospects for Fundamental Physics with LISA
Enrico Barausse, Emanuele Berti, Thomas Hertog +318
In this paper, which is of programmatic rather than quantitative nature, we aim to further delineate and sharpen the future potential of the LISA mission in the area of fundamental…