12 citations · 12 across the 9 of their papers we have counts for
11 papers
Nonlinear evolution in Galileon EFTs: Regularization and screening
Farid Thaalba, Aaron Held, Ramiro Cayuso +1
In a scalar effective field theory (EFT) with Galileon symmetry, we distinguish the strong-field expansion from the derivative expansion and study spherically symmetric classical n…
A parity selection rule for regular black holes
Farid Thaalba, Julio Arrechea, Stefano Liberati
Regular black hole metrics are usually studied kinematically, but a finite-curvature static core does not guarantee that the underlying theory can consistently evolve generic matte…
Higher-derivative gravitational effective field theories are generically weakly hyperbolic
Farid Thaalba, Fernando Abalos, Miguel Bezares
We analyse the initial-value problem of metric higher-derivative effective theories of gravity. We show that any such theory whose characteristic velocities are independent of deri…
A well-posed BSSN-type formulation for scalar-tensor theories of gravity with second-order field equations
Harry L. H. Shum, Llibert Aresté Saló, Farid Thaalba +2
Recent developments in the modified harmonic and modified puncture gauges have opened new possibilities for performing stable numerical evolutions beyond General Relativity. In thi…
Screening of dipolar emission in two-scale Gauss-Bonnet gravity
Farid Thaalba, Leonardo Gualtieri, Thomas P. Sotiriou +1
We study black holes in shift-symmetric scalar Gauss-Bonnet gravity extended by a cubic Galileon interaction with a distinct energy scale. Introducing this hierarchy profoundly mod…
Supermassive black hole scalarization and effective field theory
Farid Thaalba, Pedro G. S. Fernandes, Thomas P. Sotiriou
A model in which black hole scalarization occurs for supermassive black holes, while their less massive counterparts remain unscalarized, has been recently proposed. We explore whe…
Hyperbolicity in scalar-Gauss-Bonnet gravity: a gauge invariant study for spherical evolution
Farid Thaalba, Nicola Franchini, Miguel Bezares +1
We study spherical evolution in scalar-Gauss-Bonnet gravity with additional Ricci coupling and use the gauge-invariant approach of Ref.~\cite{Reall:2021voz} to track well-posedness…
The dynamics of spherically symmetric black holes in scalar-Gauss-Bonnet gravity with a Ricci coupling
Farid Thaalba, Nicola Franchini, Miguel Bezares +1
We study the dynamics of spherically symmetric black holes in scalar Gauss-Bonnet gravity with an additional coupling between the scalar field and the Ricci scalar using non-linear…
Exotic compact objects and light bosonic fields
Farid Thaalba, Giulia Ventagli, Thomas P. Sotiriou
In this note, we discuss the effect of light, non-gauge, bosonic degrees of freedom on the exterior spacetime of an exotic compact object. We show that such fields generically intr…
Spherical collapse in scalar-Gauss-Bonnet gravity: taming ill-posedness with a Ricci coupling
Farid Thaalba, Miguel Bezares, Nicola Franchini +1
We study spherical collapse of a scalar cloud in scalar-Gauss-Bonnet gravity - a theory in which black holes can develop scalar hair if they are in a certain mass range. We show th…
Black hole minimum size and scalar charge in shift-symmetric theories
Farid Thaalba, Georgios Antoniou, Thomas P. Sotiriou
It is known that, for shift-symmetric scalars, only a linear coupling with the Gauss-Bonnet invariant can introduce black hole hair. Such hairy black holes have a minimum mass, det…