Related papers: Scalarized Black Holes
Recent developments in the field of gravitational physics, including the emergence of gravitational wave astronomy, black hole images, and more accurate telescopes, have allowed us to probe the strong-field character of gravity in a novel…
Black-hole perturbation theory is a useful tool to investigate issues in astrophysics, high-energy physics, and fundamental problems in gravity. It is often complementary to fully-fledged nonlinear evolutions and instrumental to interpret…
Production of high-energy gravitational objects is a common feature of gravitational theories. The primordial universe is a natural setting for the creation of black holes and other nonperturbative gravitational entities. Cosmic black holes…
Black holes are among the most intriguing objects in modern physics. Their influence ranges from powering quasars and other active galactic nuclei, to providing key insights into quantum gravity. We review the observational evidence for…
Black holes in scalar-Gauss-Bonnet gravity are prone to scalarization, that is a spontaneous development of scalar hair for strong enough spacetime curvature while the weak field regime of the theory coincides with general relativity. Since…
It is recently shown that, besides the Schwarzshcild black hole solution, there exist also scalarized black hole solutions in some Einstein-scalar-Gauss-Bonnet theories. In this paper, we construct analytical expressions for the metric…
Gravitational wave observations can test the validity of General Relativity (GR) in the strong field regime. Certain classes of scalar-tensor theories indeed predict that compact objects can exhibit significant deviations from their GR…
A class of exact regular spherically symmetric solutions to the Einstein equation obeying Dymnikova's definition of the vacuumlike state is considered. These solutions, which may be interpreted as black holes, are not only singularity free,…
Since Stephen Hawking discovered that black holes emit thermal radiation, black holes have become the theoretical laboratories for testing our ideas on quantum gravity. This dissertation is devoted to the study of singularities, the…
From the microscopic point of view, realistic black holes are time-dependent and the teleological concept of event horizon fails. At present, the apparent or the trapping horizon seem its best replacements in various areas of black hole…
The extreme-gravity collisions of binaries with one black hole and one neutron star provide for excellent tests of general relativity. We here study how well one can constrain theories beyond general relativity with additional scalar fields…
The prediction of spacetime singularities, regions of infinite curvature where classical physics breaks down, is one of the most profound challenges in General Relativity (GR). In particular, black hole solutions such as the Schwarzschild…
Scalar-tensor theories of gravity generally violate the strong equivalence principle, namely compact objects have a suppressed coupling to the scalar force, causing them to fall slower. A black hole is the extreme example where such a…
It is shown that space curvature can be disposed of by properly taking into account gravitational self energies. This leads to a parameter free modification of Newton's law, violating Gauss theorem, which accounts for the crucial tests of…
Hawking has proven that black holes which are stationary as the endpoint of gravitational collapse in Brans--Dicke theory (without a potential) are no different than in general relativity. We extend this proof to the much more general class…
Fast variability studies of accreting black holes in the Galaxy offer us a unique opportunity to measure the spins of black holes and test the strong-field behavior of general relativity. In this review, I summarize the arguments often used…
The article summarizes the observational evidence for the existence of massive black holes, as well as the current knowledge about their abundance, their mass and spin distributions, and their cosmic evolution within and together with their…
As a mysterious celestial body predicted by General Relativity, black holes have been confirmed by observations in recent years. But there are still many unknown properties waiting for us to discover, one of the famous problems is the…
Scalarized black holes (BH) have been shown to form dynamically in extended-scalar-tensor theories, either through spontaneous scalarization -- when the BH is unstable against linear perturbations -- or through a non-linear scalarization.…
The recent observation of gravitational waves confirms one of the most interesting predictions in general relativity: the black holes. Because the gravitational waves detected by LIGO fit very well within general relativity as a phenomenon…