Outputs (37)

Shadows and properties of spin-induced scalarized black holes with and without a Ricci coupling (2024)
Journal Article
Fernandes, P. G., Burrage, C., Eichhorn, A., & Sotiriou, T. P. (2024). Shadows and properties of spin-induced scalarized black holes with and without a Ricci coupling. Physical Review D, 109(10), Article 104033. https://doi.org/10.1103/physrevd.109.104033

In this work, we explore the properties and shadows of spin-induced scalarized black holes, as well as investigate how a Ricci coupling influences them. Our findings reveal significant deviations from the Kerr metric in terms of the location and geod... Read More about Shadows and properties of spin-induced scalarized black holes with and without a Ricci coupling.

Ringdowns for black holes with scalar hair: The large mass case (2024)
Journal Article
D’Addario, G., Padilla, A., Saffin, P. M., Sotiriou, T. P., & Spiers, A. (2024). Ringdowns for black holes with scalar hair: The large mass case. Physical Review D, 109(8), Article 084046. https://doi.org/10.1103/physrevd.109.084046

Deviations from general relativity can alter the quasinormal mode (QNM) ringdown of perturbed black holes. It is known that a shift-symmetric (hence massless) scalar can only introduce black hole hair if it couples to the Gauss-Bonnet invariant, in w... Read More about Ringdowns for black holes with scalar hair: The large mass case.

Measuring scalar charge with compact binaries: High accuracy modeling with self-force (2024)
Journal Article
Spiers, A., Maselli, A., & Sotiriou, T. P. (2024). Measuring scalar charge with compact binaries: High accuracy modeling with self-force. Physical Review D, 109(6), Article 064022. https://doi.org/10.1103/physrevd.109.064022

Using the self-force approach, we present the premier first-post-adiabatic accuracy formalism for modeling compact binaries in theories with a massless scalar field nonminimally coupled to gravity. We limit the binary secondary to being a non-spinnin... Read More about Measuring scalar charge with compact binaries: High accuracy modeling with self-force.

Spontaneous scalarization (2024)
Journal Article
Doneva, D. D., Ramazanoǧlu, F. M., Silva, H. O., Sotiriou, T. P., & Yazadjiev, S. S. (2024). Spontaneous scalarization. Reviews of Modern Physics, 96(1), Article 015004. https://doi.org/10.1103/revmodphys.96.015004

Scalarization is a mechanism that endows strongly self-gravitating bodies, such as neutron stars and black holes, with a scalar-field configuration. It resembles a phase transition in that the scalar configuration appears only when a certain quantity... Read More about Spontaneous scalarization.

Spherical collapse in scalar-Gauss-Bonnet gravity: Taming ill-posedness with a Ricci coupling (2024)
Journal Article
Thaalba, F., Bezares, M., Franchini, N., & Sotiriou, T. P. (2024). Spherical collapse in scalar-Gauss-Bonnet gravity: Taming ill-posedness with a Ricci coupling. Physical Review D, 109(4), L041503. https://doi.org/10.1103/physrevd.109.l041503

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 that an additional quadratic coupling of the scalar field to the Ricci sca... Read More about Spherical collapse in scalar-Gauss-Bonnet gravity: Taming ill-posedness with a Ricci coupling.

Incompatibility of gravity theories with auxiliary fields with the standard model (2024)
Journal Article
Ventagli, G., Pani, P., & Sotiriou, T. P. (2024). Incompatibility of gravity theories with auxiliary fields with the standard model. Physical Review D, 109(4), Article 044002. https://doi.org/10.1103/physrevd.109.044002

Theories of gravity with auxiliary fields are of particular interest since they are able to circumvent Lovelock’s theorem while avoiding the introduction of new degrees of freedom. This type of theories introduces derivatives of the stress-energy ten... Read More about Incompatibility of gravity theories with auxiliary fields with the standard model.

Detecting Massive Scalar Fields with Extreme Mass-Ratio Inspirals (2023)
Journal Article
Barsanti, S., Maselli, A., Sotiriou, T. P., & Gualtieri, L. (2023). Detecting Massive Scalar Fields with Extreme Mass-Ratio Inspirals. Physical Review Letters, 131(5), Article 051401. https://doi.org/10.1103/physrevlett.131.051401

We study the imprint of light scalar fields on gravitational waves from extreme mass-ratio inspirals—binary systems with a very large mass asymmetry. We first show that, to leading order in the mass ratio, any effects of the scalar on the waveform ar... Read More about Detecting Massive Scalar Fields with Extreme Mass-Ratio Inspirals.

Black hole minimum size and scalar charge in shift-symmetric theories (2023)
Journal Article
Thaalba, F., Antoniou, G., & Sotiriou, T. P. (2023). Black hole minimum size and scalar charge in shift-symmetric theories. Classical and Quantum Gravity, 40(15), Article 155002. https://doi.org/10.1088/1361-6382/acdd42

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, determined by the coupling of this interaction, and a scalar charge that... Read More about Black hole minimum size and scalar charge in shift-symmetric theories.

Extreme mass-ratio inspirals as probes of scalar fields: Eccentric equatorial orbits around Kerr black holes (2022)
Journal Article
Barsanti, S., Franchini, N., Gualtieri, L., Maselli, A., & Sotiriou, T. P. (2022). Extreme mass-ratio inspirals as probes of scalar fields: Eccentric equatorial orbits around Kerr black holes. Physical Review D, 106(4), Article 044029. https://doi.org/10.1103/physrevd.106.044029

We study binary systems in which a stellar mass compact object spirals into a massive black hole, known as extreme mass ratio inspirals, in scenarios with a new fundamental scalar field. Earlier work has shown that, in most interesting such scenarios... Read More about Extreme mass-ratio inspirals as probes of scalar fields: Eccentric equatorial orbits around Kerr black holes.

Stable spontaneously-scalarized black holes in generalized scalar-tensor theories (2022)
Journal Article
Antoniou, G., Macedo, C. F., McManus, R., & Sotiriou, T. P. (2022). Stable spontaneously-scalarized black holes in generalized scalar-tensor theories. Physical Review D, 106(2), Article 024029. https://doi.org/10.1103/physrevd.106.024029

It has been shown that the synergy of a scalar field coupling with both the Ricci scalar and the Gauss-Bonnet invariant significantly affects the properties of scalarized black holes and neutron stars, including their domain of existence and the amou... Read More about Stable spontaneously-scalarized black holes in generalized scalar-tensor theories.