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Related papers: Gravitational Lensing by Black Holes

200 papers

Quantum-gravity effects in black holes are generally expected to be unobservable if they set in at transplanckian curvature scales. Here, we challenge this expectation. A near-critical spin parameter can serve as a lever arm that translates…

General Relativity and Quantum Cosmology · Physics 2023-02-01 Astrid Eichhorn , Aaron Held

Accretion onto black holes often proceeds via an accretion disc or a temporary disc-like pattern. Variability features, observed in the light curves of such objects, and theoretical models of accretion flows suggest that accretion discs are…

High Energy Astrophysical Phenomena · Physics 2016-06-01 V. Karas

Gravitational lensing of background compact objects like active galactic nuclei and quasars, by extended intermediate mass lenses such as globular clusters and and dark matter clumps with masses 10^5 - 10^8 M_sun, is considered. It is shown…

Astrophysics · Physics 2008-09-22 Yu. L. Bukhmastova , Yu. V. Baryshev

Observational measurements of the relationship between supermassive black holes (SMBHs) and the properties of their host galaxies are an important method for probing theoretical hierarchical growth models. Gravitational lensing is a unique…

Astrophysics · Physics 2009-11-10 Judd D. Bowman , Jacqueline N. Hewitt , James R. Kiger

Black holes are extreme outcomes of General Relativity, and can form through a variety of ways, including gravitational collapse of massive stars, or quantum fluctuations in the early universe. Here, we ask the question of whether they can…

General Relativity and Quantum Cosmology · Physics 2025-02-04 Diego Blas , Vitor Cardoso , Jose María Ezquiaga

In the present work, we investigate the gravitational lensing effects of two quantum-modified black hole models recently proposed in effective quantum gravity. The light deflection angles are calculated for both the weak-field and…

General Relativity and Quantum Cosmology · Physics 2024-11-20 Hao Liu , Meng-Yun Lai , Xiao-Yin Pan , Hyat Huang , De-Cheng Zou

Recent advances, including gravitational wave detections and imaging of black hole shadows, have strongly validated general relativity. Nevertheless, ongoing cosmological observations suggest potential limitations of general relativity,…

General Relativity and Quantum Cosmology · Physics 2025-08-11 Ali Övgün , Mohsen Fathi

We study the gravitational lensing influence of a massive object in a dark matter halo, using a simple model of a point mass embedded in a spherical Navarro--Frenk--White halo. Building on the analysis of critical curves and caustics…

Astrophysics of Galaxies · Physics 2022-03-14 Michal Karamazov , David Heyrovsky

Gravitational lensing has now become a popular tool to measure the mass distribution of structures in the Universe on various scales. Here we focus on the study of galaxy's scale dark matter halos with galaxy-galaxy lensing techniques:…

Astrophysics · Physics 2007-05-23 M. Limousin , J-P. Kneib , P. Natarajan

We study regular and asymptotically flat phantom black holes as gravitational lenses. We obtain the deflection angle in both the weak and the strong deflection limits, from which we calculate the positions, magnifications, and time delays…

General Relativity and Quantum Cosmology · Physics 2013-11-27 Ernesto F. Eiroa , Carlos M. Sendra

General Relativity effects (gravitational redshift, light bending, ...) strongly modify the characteristics of the lines emitted close to the Black Hole in Active Galactic Nuclei and Galactic Black Hole systems. These effects are reviewed…

Astrophysics · Physics 2010-11-11 Giorgio Matt

We investigate the strong gravitational lensing phenomena caused by a black hole with a dark matter halo. In this study, we examine strong gravitational lensing with two significant dark matter models: the universal rotation curve model and…

General Relativity and Quantum Cosmology · Physics 2023-11-03 Niyaz Uddin Molla , Himanshu Chaudhary , Dhruv Arora , Farruh Atamurotov , Ujjal Debnath , G. Mustafa

In the standard paradigm, astrophysical black holes can be described solely by their mass and angular momentum - commonly referred to as `spin' - resulting from the process of their birth and subsequent growth via accretion. Whilst the mass…

High Energy Astrophysical Phenomena · Physics 2017-12-19 Matthew Middleton

We try to explain quasar-galaxy associations by gravitational lensing by globular clusters, located in the halos of foreground galaxies. We propose observational test for verification of this hypothesis. We processed SUPERCOSMOS sky survey…

Astrophysics · Physics 2007-05-23 A. Yushchenko , Chulhee Kim , A. Sergeev , P. Niarchos , V. Manimanis

We study how the angular resolution of LISA for merging massive black-hole binaries would be improved if we observe multiple gravitational wave ``images'' due to strong gravitational lensing. The correlation between fitting parameters is…

Astrophysics · Physics 2009-11-07 Naoki Seto

Braneworld black holes existing today may be of primordial origin, or may even be produced in high energy particle collisions in the laboratory and in cosmic ray showers as well. These black holes obey a modified mass-radius relationship…

Astrophysics · Physics 2008-11-26 A. S. Majumdar , Nupur Mukherjee

We study the gravitational lensing scenario where the lens is a spherically symmetric charged black hole (BH) surrounded by quintessence matter. The null geodesic equations in the curved background of the black hole are derived. The…

General Relativity and Quantum Cosmology · Physics 2017-06-21 Mustapha Azreg-Aïnou , Sebastian Bahamonde , Mubasher Jamil

In this letter, we investigate the strong gravitational lensing effects around two classes of rotating regular black holes, which behave as non-singular Minkowski core at the center. Starting from the null geodesic in the equatorial plane…

General Relativity and Quantum Cosmology · Physics 2025-01-07 Mingyu Guo , Menghe Wu , Hong Guo , Xiaomei Kuang , Fuyao Liu

We present the first detailed computations of wave optics effects in the gravitational lensing of binary systems. The field is conceptually rich, combining the caustic singularities produced in classical gravitational lensing with quantum…

General Relativity and Quantum Cosmology · Physics 2020-08-06 Job Feldbrugge , Neil Turok

Weak gravitational lensing is a unique probe of the dark side of the universe: it provides a direct way to map the distribution of dark matter around galaxies, clusters of galaxies and on cosmological scales. Furthermore, the measurement of…

Astrophysics · Physics 2010-01-07 Henk Hoekstra , Bhuvnesh Jain