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Related papers: Compact astrophysical objects in modified gravity

200 papers

In this paper, we follow up on the discovery of a new type of solution in the Einstein-Maxwell system coupled minimally to a self-interacting complex scalar field. For sufficiently large gravitational coupling and sufficiently small…

General Relativity and Quantum Cosmology · Physics 2022-06-08 Yves Brihaye , Betti Hartmann

The detection of gravitational waves (GWs) propagating through cosmic structures can provide invaluable information on the geometry and content of our Universe, as well as on the fundamental theory of gravity. In order to test possible…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Alice Garoffolo , Gianmassimo Tasinato , Carmelita Carbone , Daniele Bertacca , Sabino Matarrese

Since the discovery of the accelerated expansion of the present Universe, significant theoretical developments have been made in the area of modified gravity. In the meantime, cosmological observations have been providing more high-quality…

Over the next decade, third-generation interferometers and the space-based LISA mission will observe binaries in galactic centers involving supermassive black holes with millions of solar masses. More precise measurements of more extreme…

General Relativity and Quantum Cosmology · Physics 2023-08-09 Francisco Duque

Multipole moments are related to the physical properties of compact gravitating objects; therefore, understanding their structure is useful in accessing the nature of compact objects. We look into gravitational wave observables for black…

General Relativity and Quantum Cosmology · Physics 2025-03-04 Anirban Saha

We consider a gravitating system of vanishing cosmological constant consisting of an electromagnetic field and a scalar field coupled to the Einstein tensor. A Reissner-Nordstr\"om black hole undergoes a second-order phase transition to a…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Theodoros Kolyvaris , George Koutsoumbas , Eleftherios Papantonopoulos , George Siopsis

Future observations of the large-scale structure have the potential to investigate cosmological models with a high degree of complexity, including the properties of gravity on large scales, the presence of a complicated dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-26 Robert Reischke , Alessio Spurio Mancini , Björn Malte Schäfer , Philipp M. Merkel

General relativity has passed all solar system experiments and neutron star based tests, such as binary pulsar observations, with flying colors. A more exotic arena for testing general relativity is in systems that contain one or more black…

General Relativity and Quantum Cosmology · Physics 2016-02-19 Kent Yagi , Leo C. Stein

We introduce a family of solutions of Einstein's gravity minimally coupled to an anisotropic fluid, describing asymptotically flat black holes with "hair" and a regular horizon. These spacetimes can describe the geometry of galaxies…

General Relativity and Quantum Cosmology · Physics 2022-03-23 Vitor Cardoso , Kyriakos Destounis , Francisco Duque , Rodrigo Panosso Macedo , Andrea Maselli

Recently, a no inner (Cauchy) horizon theorem for static black holes with non-trivial scalar hairs has been proved in Einstein-Maxwell-scalar theories. In this paper, we extend the theorem to the static black holes in…

High Energy Physics - Theory · Physics 2022-04-20 Deniz O. Devecioglu , Mu-In Park

We establish the existence of time-dependent solitons in a modified gravity framework, which is defined by the low energy limit of theories with a weakly broken galileon symmetry and a mass term. These are regular vacuum configurations of…

General Relativity and Quantum Cosmology · Physics 2021-10-18 Juan Barranco , Javier Chagoya , Alberto Diez-Tejedor , Gustavo Niz , Armando A. Roque

The no-hair theorem postulates that the only externally observable properties of a black hole are its mass, its electric charge, and its angular momentum. In scalar-tensor theories of gravity, a matter distribution around a black hole can…

General Relativity and Quantum Cosmology · Physics 2017-09-14 Tomi Koivisto , Hannu J. Nyrhinen

We study the properties of compact objects in a particular 4D Horndeski theory originating from higher dimensional Einstein-Gauss-Bonnet gravity. Remarkably, an exact vacuum solution is known. This compact object differs from general…

General Relativity and Quantum Cosmology · Physics 2022-03-02 Christos Charmousis , Antoine Lehébel , Evangelos Smyrniotis , Nikolaos Stergioulas

We parametrize a large class of corrections to general relativity which include a long-ranged gravitational scalar field as a dynamical degree of freedom in two ways: parametrizing the structure of the correction to the action, and…

General Relativity and Quantum Cosmology · Physics 2014-08-25 Leo C. Stein , Kent Yagi

We study a number of well-motivated theories of modified gravity with the common overarching theme that they predict the existence of compact objects such as black holes and wormholes endowed with scalar hair. We compute the shadow radius…

General Relativity and Quantum Cosmology · Physics 2024-11-13 Georgios Antoniou , Alexandros Papageorgiou , Panagiota Kanti

With the recent progress in observations of astrophysical black holes, it has become more important to understand in detail the physics of strongly gravitating horizonless objects. If the objects identified in the observations are indeed…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Ufuk Aydemir , Jing Ren

We consider a general class of quantum gravity-inspired, modified gravity theories, where the Einstein-Hilbert action is extended through the addition of all terms quadratic in the curvature tensor coupled to scalar fields with standard…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Kent Yagi , Leo C. Stein , Nicolas Yunes , Takahiro Tanaka

We consider spatially covariant modified gravity in which the would-be scalar degree of freedom is made non-dynamical and hence there are just two tensorial degrees of freedom, i.e., the same number of dynamical degrees of freedom as in…

General Relativity and Quantum Cosmology · Physics 2021-12-15 Aya Iyonaga , Tsutomu Kobayashi

According to the no-hair theorem, static black holes are described by a Schwarzschild spacetime provided there are no other sources of the gravitational field. This requirement, however, is in astrophysical realistic scenarios often…

General Relativity and Quantum Cosmology · Physics 2015-06-24 Norman Gürlebeck

We investigate the structure of nontrivial maximally symmetric vacua and compact-object solutions in shift-symmetric scalar-tensor theories. Focusing on Horndeski gravity, we derive consistency conditions directly from the field equations…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Athanasios Bakopoulos , Christos Charmousis , Nikos Chatzifotis , Theodoros Nakas